Browse Topic: Gases

Items (3,893)

Identification and Quantification of PAHs in Gasoline Soot Using ASE-GC-MS/MS

2026-99-0110

7/31/2026

In the present work, a novel method that combines accelerated solvent extraction (ASE) and gas chromatography coupled with triple quadrupole tandem mass spectrometry (GC-MS/MS) was proposed to identify and quantify polycyclic aromatic hydrocarbons (PAHs) in gasoline soot. The n-hexane was employed to extract the target analytes, and the optimal extraction conditions were identified (cycle times = 3, extraction time = 30 min, extraction temperature = 120°C, and extraction pressure = 100 MPa). The extraction efficiency of six analytes was measured to assess the ASE method; the formation mechanism of partial PAHs was discussed, and the 18 PAHs in gasoline soot were studied both qualitatively and quantitatively under the optimal conditions. It was found that our new method reached a high correlation coefficient (between 0.9987 and 0.9997); the limits of quantification (LOQs) (S/N = 6) for these PAHs were between 0.003 and 0.009 ng/mL with a relative standard deviation (RSD) of 2.9–10.6%. Our method demonstrated good performance in determining the target analytes in soot samples, such as gasoline soot, some materials soot, co-combustion soot, gasoline, and materials. The PAHs differences in soot samples containing gasoline and materials soot samples were significant enough to obtain the observed discrimination. The method is an accurate and sensitive quantitative method to identify gasoline residues in soot samples of arson fire.

Liu, Shujun, Cao, Henan, Qi, Lijie, Liu, Yang, Li, Qi

Study on Formulation Design of Solvent-Free In-Situ Curing Liquid Rubber for Vacuum Sealing Materials

2026-99-0203

7/31/2026

This study adopts a solvent-free in-situ molding process, using liquid ethylene-propylene-diene monomer (LEPDM) as the base rubber to prepare vacuum sealing materials. The effects of the blending ratio of EPDM/LEPDM on mechanical properties, processing characteristics, physical-mechanical properties, compression characteristics, and vacuum condensable volatiles were investigated. The influence of lamellar intercalated structural fillers on gas permeability was also examined. The results indicate that the addition of LEPDM significantly reduces the Mooney viscosity, improves filler dispersion, and achieves good processability. When the LEPDM blending amount exceeds 20 phr, significant changes occur in mechanical properties, compression modulus, and compression set, which are related to phase transformation. Vacuum pretreatment and vacuum condensable volatile test results show that the traditional plasticizer DOP exhibits high total mass loss (TML) and collected volatile condensable materials (CVCM). However, when LEPDM is partially used to replace EPDM at a blending ratio of 20 phr, TML ≤ 1% and CVCM ≤ 0.1% can be achieved. With the increase in organically modified montmorillonite (OMMT) content, the gas permeability coefficient first decreases and then increases. When the OMMT content is 15 phr, the material exhibits good gas barrier properties

Han, Xiao, Shi, Lei, Chen, Zongwen, Zhang, Zhaoyang, Cheng, Wei

Study on Stiffness Model of Bump Foil in Bump Foil Gas Bearings Based on Ansys Simulation Considering Axial Variable Loads

2026-99-0174

7/31/2026

To address the inaccuracy of existing models in describing the stiffness distribution along the axial direction of bump foils, this study first establishes a simulation model applicable to bump foils based on Ansys Workbench. Specifically, by applying axial variable load at a node that matches the distribution of actual operating conditions, the deformation and stiffness characteristics of the bump foil are investigated. The research results show that, compared with the classic Heshmat model, the bump foil stiffness is not uniformly distributed in the axial direction; instead, it exhibits a trend of being higher in the middle and lower at both ends. Notably, when the nominal stiffness values are similar, the axial end displacement obtained from the Ansys simulation differs significantly from the result calculated by the Heshmat model, with the deviation reaching up to 17.7% of the peak displacement from the latter. Furthermore, this study also systematically analyzes the influence of the laws of the bump foil’s curvature radius, length, and friction coefficient on its stiffness.

Wu, Yixuan, Shi, Yiming, Zhu, Jianjun, Liu, Jiajie

Characterization of Dynamic Characteristics of Pneumatic Systems Based on Aerodynamic Frequency Ratio

2026-99-0230

7/31/2026

To address the ambiguity in the relationship between design parameters and energy characteristics in pneumatic systems caused by gas compressibility and low viscosity, which leads to design redundancy, this paper proposes a dynamic characteristic characterisation method based on the pneumatic frequency ratio. This aims to establish a correlation mechanism between system energy consumption and dynamic performance. By constructing a nonlinear dynamic model of a double-acting cylinder, the dimensionless aerodynamic frequency ratio (Ω) is defined to characterise the matching relationship between the system’s natural and operating frequencies. Analytical relationships between Ω and key design parameters—such as cylinder diameter and valve sound velocity conductance—are derived, thereby establishing a normalised similarity criterion. Through combined simulation analysis and experimental validation, the regulatory patterns of Ω on the dynamic characteristics of displacement, velocity, and pressure are systematically investigated. Results indicate that under consistent Ω conditions, the normalised dynamic characteristic error across aerodynamic systems with varying parameters can be controlled within 4%. A significant linear correlation exists between the frequency ratio and the amplitude of cylinder chamber pressure differentials, with errors below 3%. The study further reveals that Ω exerts a nonlinear regulatory effect on system responsiveness and stability: increasing Ω enhances dynamic response speed but exacerbates pressure fluctuations, whereas decreasing Ω slows response but improves pressure stability. This methodology provides a theoretical foundation for energy-efficient design, parameter matching, and intelligent control of pneumatic systems, effectively addressing a gap in existing research on energy-dynamics coupling analysis.

Li, Mengru, Du, Hongwang, Wang, Jiajia, Yuan, Tingting, Xiong, Wei

Research and Application of Mechanical Voltage Stabilization Control Device

2026-99-0119

7/31/2026

This study carefully designed and successfully developed a mechanical voltage stabilizing control device. The device uses silicone oil as the key component material of the liquid spring and 1Cr13 as the main material of the pressure control unit, enhancing its high-pressure resistance (up to 35 MPa), oxidation resistance, and acid-alkali corrosion resistance. By optimizing the transmission mechanism and simplifying the pressure regulation module, the device achieves a pressure regulation range of 0.1–21 MPa with an accuracy of ±0.01 MPa, significantly broader and more precise than traditional devices. To address manufacturing challenges, advanced CNC machine tools, ceramic cutting tools, and optimized heat treatment processes (e.g., quenching and tempering) were adopted, ensuring component machining accuracy within ±0.02 mm. Field applications in 13 oil wells demonstrated a 15.6% increase in daily oil production (from 25.5 t/d to 29.5 t/d) and a 17.9% increase in daily gas production (from 2800 m^3/d to 3300 m^3/d), with stable casing pressure control at 5.3 MPa. The device has created 1.225 million yuan in economic benefits while eliminating safety hazards, providing critical technical support for efficient and environmentally friendly oil and gas production.

Wang, Gang, Liu, Cuicui, Tong, Deshui, Cao, Jian, Mu, Taiji, Han, Baidong

Microstructure and Properties of 316L Stainless Steels Modified with C and Cr Elements

2026-99-0217

7/31/2026

SiC-based power devices are favored for high-voltage and high-power applications due to their superior material properties. However, the demand for higher breakdown voltages and improved channel mobility presents significant challenges to the etching process, especially the micro-trenching effect. In this study, etching results from inductively coupled plasma (ICP) have been presents, which focused on using various SF6/O2/Ar gas ratios to eliminate micro-trenching effect. The profile analysis of micro-trench was taken by cross-sectional scanning electron microscopy (SEM). The results demonstrate that micro-trenches primarily originate from the coupling effect between ion multi-reflection from sidewalls and redeposition of etch byproducts. Based on this mechanism, we propose a quasi-Bosch process: a combined polymerization and etching step in oxygen-fluorine-rich plasma deposits polymer on exposed SiC and the mask, while removing it from the structure bottom via ion bombardment to enable etching and passivation; then alternates with a short fluorine-plasma step, which consumes sidewall polymer through ion incidence and prevents SiFxOy charge accumulation, cycle etching gradually deepens the structure without micro-trenches. Different gas ratios and etching time not only change the plasma energy distribution but also affect the temporal synchronization between etching and passivation steps. This approach reduces the special demands on ICP equipment capabilities while achieving superior trench profiles. The optimal etching conditions produced a micro-trench-free SiC structure with a vertical sidewall angle and a surface roughness of less than 1 nm. This methodology and resulting structures significantly advance the manufacturability of high-performance SiC power devices, enabling next-generation applications in electric vehicles and grid infrastructure where device yield and reliability are paramount.

Zhao, Yingfan, Dong, Shuang, Sun, Xiaoxu, Chang, Xiangpeng, Liang, Yiwei, Tong, Weiping

Biomimetic Design and Numerical Analysis of a VIV Suppression Fairing for Offshore Risers

2026-99-1640

7/24/2026

As oil and gas exploitation advances into deep seas, risers linking offshore platforms and subsea extraction systems endure long-term complex marine loads. Fatigue damage from Vortex-Induced Vibration (VIV) has become a key factor limiting the safe operation of deep-sea engineering structures. To address this issue, a bionic adaptive rotating fairing, which is adjustable to ocean current directions, was designed. Its main components include buoyancy blocks, a fairing with spiral guide rails on the inner wall, and clamps, which work together to reduce VIV by regulating flow patterns. Numerical simulations of concave and convex fairings showed that under subcritical flow, shifting from a concave to convex cross-section gradually enhances the fairing’s drag and lift reduction effects on risers, with a steady improvement trend. Further comparisons were made between 0.25D convex fairings, 0.35D convex fairings, and bare risers, focusing on drag/lift reduction, vortex shedding frequency, and Strouhal number. Both convex fairings exhibited similar VIV suppression performance to the bare riser, but differed significantly in the percentage reduction of vortex shedding frequency and Strouhal number. Thus, the 0.25D convex fairing was identified as the optimal configuration for VIV suppression among the concave-convex fairings studied.

Zhang, Xu, Song, Guangming, Wang, Baozhong, Zhao, Jinpeng, Chen, Qianshuo

From Racing Car to Rocket Tank

26AERP06_08

6/1/2026

German startup Blackwave is building carbon parts for rocket tanks. Technical University of Munich, Munich, Germany Carbon fiber has become indispensable in high-performance industries such as automotive engineering and aerospace. It's lightweight, extremely durable, and can be shaped in almost any way. The start-up Blackwave, founded at the Technical University of Munich (TUM), specializes in this versatile composite material. What began with custom components for sports cars and aircraft has evolved into the development of high-pressure tanks for space applications. As is so often the case in engineering, a small detail determines technological progress. In the case of rockets, it is the high-pressure tanks that are specially designed for the fuel systems. As rockets are designed to be as light as possible, they lose structural stability when the fuel tanks, known as primary tanks, are emptied. A trick is used to counteract this: alongside fuel combustion, noble gases are released from internal high-pressure tanks, known as secondary tanks. These gases fill the resulting empty space, maintaining structural integrity.

Process Optimization of Ni: PEEK Cold Sprayed Layers to Form Erosion Coatings on Helicopter Rotor Blades

F-0082-2026-0107

5/5/2026

Cold spray deposition is a kinetic-based deposition method that uses an inert gas flow to accelerate particles, where kinetic energy causes plastic deformation upon impact with a substrate, as discussed in Reference 1. Cold spray has been investigated as a method to deposit metal coatings on polymer-based composites, such as aerospace carbon-fiber-reinforced plastics (CFRP's), as discussed in Reference 2. These methods also exhibit low deposition efficiency (15-45%) as shown in Reference 3. In this work, to achieve high deposition efficiency and create an erosion-resistant coating, we use metal-polymer composite powders for cold spray, to make polymer-on-polymer bonding the dominant and effective bonding mechanism; this method lowers impact velocities relative to pure metal deposition to avoid substrate damage. The polymer can also lower the effect of material mismatch, while the nickel can help enhance the erosion performance of the final coating above that of pure polymer. This paper discusses the development of the cold spray deposition process, sample post-processing, erosion testing, and characterization of the samples. The results validate that this method successfully creates a method of depositing a coating with erosion resistance approaching that of bulk titanium without substrate damage on PEEK substrates. Further work is needed to address the issues with depositing on CF-PEEK substrates.

Fischer, Brandon, Wolfe, Douglas, Ryan, Caillin, DeSalle, Chris, Yamamoto, Namiko

Application of DFSS for Optimizing Thermal Protection in Electric Vehicles during Battery Thermal Runaway Events

2026-01-0142

4/7/2026

Battery thermal runaway is a major safety concern in electric vehicles because of the extreme heat and hazardous gases released during cell failure. These venting events can quickly raise the temperature of the battery enclosure and cabin floor, threatening occupant safety. To address this challenge, this study employs the Design for Six Sigma (DFSS) methodology to design and optimize a thermal protection system that delays and limits heat transfer to the cabin. A physics-based transient heat-transfer model was combined with DFSS principles to systematically evaluate insulation materials, shield layouts, surface emissivity, and layer geometry. An L-18 orthogonal array was used to identify key parameters and quantify their influence on thermal robustness. The optimized architecture reduced cabin-floor temperature rise under severe runaway conditions (600–900 °C vent gas), meeting occupant-egress safety requirements. Findings confirm DFSS as an effective framework for developing high-robustness EV thermal protection systems under uncertainty and extreme boundary conditions.

El-Sharkawy, Alaa, Asar, Mona, Taha, Nahla, Sheta, Mai

Optimization Strategies of Gliding Arc Plasma-Based Ammonia Cracker towards Onboard Applications

2026-01-0292

4/7/2026

Ammonia has emerged as a viable hydrogen energy carrier owing to its superior hydrogen density and mature industrial utilization. However, ammonia faces critical challenges including inadequate ignition characteristics and sluggish combustion kinetics, necessitating supplementary high-reactivity fuels for optimizing combustion. Onboard ammonia decomposition technology resolves this problem through on-demand hydrogen real-time production. Among existing ammonia decomposition methods, gliding arc plasma (GAP) demonstrates exceptional promise for onboard hydrogen production given its high processing flow rate，decent hydrogen conversion rate, and transient response capability. Prevailing research predominantly relies on experimental approaches, with insufficient understanding of the effects of specific electrical field parameters and inlet pressure on system performance. This study established a quasi-one-dimensional numerical model for GAP-assisted ammonia decomposition. A comprehensive analysis was conducted to examine the influence of key electric field parameters, such as reduced electric field strength (REFS) and electron density (De), on ammonia conversion rate and energy efficiency. Furthermore, the study explored the synergistic effects of inlet pressure and electric field parameters on system performance under constant mass flow rate conditions. The results indicate that increasing REFS and De significantly substantially elevates ammonia conversion rate, but energy efficiency decreases as these parameters increase. Keeping a constant NH3 inlet mass flow rate, the gas velocity decreases when the inlet pressure increases and then extends the residence time. Consequently, the ammonia conversion rate significantly improves while the energy efficiency slightly decreases. By increasing inlet pressure and simultaneously reducing REFS or De, system energy efficiency can be effectively enhanced without altering ammonia conversion rates. This study demonstrates the synergistic regulation mechanism of electric field parameters and inlet pressure on hydrogen production performance, providing optimization strategies for GAP reactor design.

Dong, Guangyu, Li, Xian, Zhou, Yanxiong, Xu, Jie, Li, Liguang

CFD Modeling of Gas Formation and Venting During the EV’s Battery Cells Manufacturing Process

2026-01-0384

4/7/2026

The battery is a critical component of electric vehicles (EVs), where high power demands pose significant operational challenges. One such challenge is gas generation within the porous anode layer, which can lead to pressure buildup inside the battery. The complex interfacial dynamics at the microscale play a crucial role in determining the effectiveness of gas venting and the resulting pressure evolution. This study examines the effect of gas generation at two different length scales on the pressure rise and bubble dynamics. First, gas generation within a representative anode microstructure sample is investigated using a Volume of Fluid (VOF) framework that resolves tortuous flow passages. The simulations reveal that gas generation in such microstructures can lead to pressure rises of several thousand Pascals, with interfacial behavior primarily governed by surface tension effects. Second, a high-level single-cell simulation is performed using a porous media approach to evaluate system-scale gas venting and localized pressurization. This multiscale modeling framework provides key insights into the relationship between microscale gas dynamics and overall gas accumulations in the cell.

Mahyawansi, Pratik J., Schlautman, Jeff, Viswanath, Priyanka, Srinivasan, Chiranth

A Novel Chemical Clustering Approach for the Acceleration of 3D CFD Simulations of Internal Combustion Engines with Complex Fuels

2026-01-0495

4/7/2026

Detailed kinetics simulations coupled with 3D CFD offer a powerful analysis tool for combustion and emissions. Such methods allow consistent modeling of multi-component fuels from evaporation to combustion and correctly capture the effects of local inhomogeneities created by preferential evaporation on the performance and emissions of modern powertrains. Such computations are extremely computationally demanding, prompting interest in the development of calculation acceleration techniques that can effectively balance the speed and accuracy of the chemical source calculation terms. Chemical kinetics clustering methods are widely used for that effect. However, such techniques must be not only effective but also robust with respect to the engine conditions and fuel composition changes, to reduce the computational demands introduced by the need to calibrate the parameters of the acceleration method itself. In this paper, an extended chemical kinetics clustering approach is proposed. A calibration methodology for the parameters of this acceleration method is then introduced, based on multi-point single time step optimization for a toluene reference fuel (TRF) surrogate with ESTECO modeFRONTIER, utilizing frozen 3D CFD fields obtained with the Realis Simulation VECTIS code. The optimal clustering parameters thus constructed are then fine-tuned through a DoE exercise performed in VECTIS for the combustion event with the TRF surrogate using a coarse computational mesh. The robustness of the optimal parameters is then evaluated through the application of different perturbations to the species fields. Finally, the optimal clustering parameters are applied to full-load simulations of a typical GDI engine with simple TRF and 8-species E10 gasoline surrogates. The results demonstrate that the acceleration parameters determined by this workflow deliver 2.4× to 4.2× acceleration of combustion source calculation and 1.3× to 1.8× acceleration of the overall simulation while preserving solution accuracy and keeping the resolution of NO and soot emissions within 10% and 15%, respectively. The proposed methodology facilitates the broader use of detailed chemistry in internal combustion engine (ICE) applications, supporting modern powertrain development needs.

Hernandez, Ignacio, Turquand d Auzay, Charles, Shapiro, Evgeniy, Shala, Mehmet, Borg, Anders, Seidel, Lars, Mauss, Fabian

Ford announces 48-volt architecture for future electric truck

26AUTP04_10

4/1/2026

Ford is seeding bits of information about its electric mid-size pickup that is slated to land in 2027. The vehicle is the brainchild of the company's skunkworks division and is set to become the standard by which other new electric vehicles from the blue oval are constructed. The underlying UEV (Universal Electric Vehicle) platform is meant to reduce the cost of EVs so they are comparable with gas vehicles. During a presentation focused on efficiency and how Ford plans to eke every mile it can out of the upcoming vehicle, the automaker shared that the vehicle would have a 48-volt architecture instead of the traditional 12-volt system via a DC-to-DC converter. The converter will step down the power from the 400-volt battery system to 48 volts to power ancillary items in the vehicle.

Baldwin, Roberto

Comprehensive Research Study Examining Tyre Wear and its Indian Perspective

2026-26-0604

1/16/2026

Automobile emissions refer to the gases and particles released into the atmosphere by vehicles during their operation. These emissions contribute to environmental pollution and have an impact on human physiology and environment. This paper assimilates findings from a comprehensive research study examining tyre wear and its Indian perspective. Tyre wear understood as a factor affecting road safety, environmental health, and economic sustainability. The study identifies factors affecting tyre wear and provides overview regarding tyre wear generation in India, encompassing road infrastructure, vehicle characteristics, driving patterns, and environmental factors. Moreover, it examines the adverse effects of these particles on human health, such as respiratory ailments and cardiovascular diseases, as well as their impact on ecosystems. This paper delves measures to measure tyre wear and safeguard both environmental and public health. It also covers the tyre wear measurement methodologies to provide a comparison of methods used for estimating tyre wear. This paper is an attempt to summarize effects of tyre wear and its Indian perspective. Specific market serves specific requirements. Bringing forward India specific perspective of tyre usage patterns, it is common observation that Indian tyre consumption pattern is different than the developed countries like other developed countries. Varied environmental conditions, road conditions and usage patterns also affect tyre wear. This paper will address various such aspects also.

Joshi, Amol, Khairatkar, Vyankatesh, Belavadi Venkataramaiah, Shamsundara

Design and Development of a Lightweight Aluminium Cascade System for Type IV COPVs for Stationary and Mobile Applications

2026-26-0485

1/16/2026

The global push for clean energy has made hydrogen a central element in decarbonizing transport, industrial processes, and energy systems. Effective hydrogen storage and distribution are critical to supporting this transition, and type IV Composite Overwrapped Pressure Vessels (COPVs) have emerged as the preferred solution due to their lightweight, high pressure capacity, hydrogen embrittlement and corrosion resistance. However, the cascade infrastructure used to house and transport these vessels has lagged behind in innovation. Steel-based cascades, while strong, are heavy prone to corrosion, and unsuitable for mobile deployment. This paper introduces a custom designed aluminium cascade system offering a 65% weight reduction while maintaining structural integrity and safety. Designed for mobile use, the system features modularity, better damping, and enhanced corrosion protection. The paper outlines design methodology, material selection, fabrication process, and comparative performance evaluation against steel cascade, supporting the advancement of hydrogen infrastructure.

Parasumanna, Ajeet Babu, Muthusamy, Hariprasad, Ammu, Vnsu Viswanath, Kola, Immanuel Raju

A Novel Approach to Optimal Strain Gauge Placement for Structural Assessment: Integrating Looping Configurations with Calibration Techniques

2026-26-0551

1/16/2026

Addressing the challenge of optimal strain gauge placement on complex structural joints and pipes, this research introduces a novel methodology combining strategic gauge configurations with numerical optimization techniques. Traditional methods often struggle to accurately capture combined loading states and real-world complexities, leading to measurement errors and flawed structural assessments [9]. For intricate joints, a looping strain gauge configuration is proposed to comprehensively capture both bending and torsional effects, preventing the bypassing of applied loads. A calibration technique is used to create strain distribution matrices and access structural behavior under different loading conditions. Optimization algorithms are then applied to identify gauge placements that yield well-conditioned matrices, minimizing measurement errors and enhancing data reliability. This approach offers a cost-effective solution by reducing the number of gauges required for accurate stress characterization. This concept is extended to both round and complex-shaped pipes to improve fatigue damage prediction using Road Load Data Acquisition (RLDA). The approach addresses geometric complexities and simulates strain behavior under diverse loading scenarios. The optimization focuses on maximizing strain sensitivity in critical regions, minimizing errors, and ensuring robust strain representation while considering RLDA constraints. The unique contribution lies in directly linking optimized strain gauge placement with improved damage calculation. By integrating RLDA, optimized configurations are tested under actual operating conditions, validating numerical models and assessing damage accumulation based on measured strain data. This leads to more realistic damage predictions compared to simplified loading assumptions. The findings demonstrate that optimized placement significantly enhances damage calculation accuracy, crucial for industries like oil and gas, aerospace, and infrastructure monitoring, where RLDA provides valuable insights into real-world loading.

Shingate, Uttam, Yadav, Dnyaneshwar, Deshpande, Onkar

Advancement in Analytical Characterization of NBR: Py-GC-MS as an Alternative to NMR for Acrylonitrile Quantification

2026-26-0546

1/16/2026

Nitrile Butadiene Rubber (NBR), known for its superior resistance to hydrocarbon oil, low gas permeability, and excellent thermal stability, finds extensive use in seals, O-rings, conveyor belts etc. Importantly, these performance attributes are chiefly governed by acrylonitrile content in NBR. Analytical characterization of raw NBR is relatively straightforward using conventional techniques such as elemental analysis (CHNS) and liquid state 13C NMR. In contrast, the analysis of vulcanized NBR presents considerable challenges due to its crosslinked structure, which renders it insoluble in most organic and inorganic solvents, thereby restricting direct molecular-level analysis. While solid-state 13C NMR is an established technique for structural characterization in rubber vulcanizates, its high-cost curbs routine industrial analysis. In this study, Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC-MS) technique has been explored as a robust, precise, cost-effective alternative. Quantitative determination of acrylonitrile (ACN) content in vulcanized NBR, covering a compositional range of 15% to 52% is carried out using Py-GC-MS. For sequence distribution of ACN units, liquid-state 13C NMR, is utilized exclusively for soluble, uncured NBR. The absolute ACN content values thus obtained serve as reference standards for validating the Py-GC-MS method, enabling robust quantification across both raw and cured material forms.

Samanta, Rajyasree, Ghosh, Debojit, Anjana, Kanhaiya, Sen, Amit, Guria, Biswanath, Chanda, Jagannath, Samui, Barun, Ghosh, Prasenjit, Mukhopadhyay, Rabindra

Early Prediction of CNG Filling Time Using Artificial Intelligence for Design Optimization

2026-26-0662

1/16/2026

Over the past few decades, Compressed Natural Gas (CNG) has gained popularity as an alternative fuel due to its lower operating cost compared to gasoline and diesel, for both passenger and commercial vehicles. In addition, it is considered more environmentally friendly and safer than traditional fossil fuels. Natural gas's density (0.7–0.9 kg/m3) is substantially less than that of gasoline (715–780 kg/m3) and diesel (849–959 kg/m3) at standard temperature and pressure. Consequently, CNG needs more storage space. To compensate for its low natural density, CNG is compressed and stored at high pressures (usually 200-250 bar) in on-board cylinders. This results in an effective fuel density of 180 kg/m3 at 200 bar and 215 kg/m3 at 250 bar. This compression allows more fuel to be stored, extending the vehicle's operating range per fill and minimising the need for refuelling. Natural Gas Vehicles (NGVs), particularly those in the commercial sector like buses and lorries, need numerous CNG cylinders in order to maximise vehicle range on a single fill. However, increasing the number of on-board cylinders results in a proportional increase in refuelling time, which can have a detrimental impact on operational costs for commercial fleet owners. The CNG fuel system, which usually consists of large-volume petrol cylinders (up to 800 litres), is an essential part of vehicle development. A quick petrol fill-up time is ideal because these vehicles must frequently refuel because they frequently travel vast miles each day. At the moment, the refuelling time is calculated by evaluating the CNG filling time following prototype development. Design modifications to the fuel system are necessary if the filling time is too long, which results in severe time and cost penalties as well as delays in the development cycle of new vehicle products. A mathematical model based on a number of influencing factors has been created by combining AI and ML technology. At the initial Zero design release gateway, this model will forecast the time needed to fill up with CNG petrol on all commercial vehicle platforms. This early prediction will enable additional optimization to improve gas filling time. The goal of this research work is to optimize the filling time for various platform before physical vehicle builds.

Choudhary, Aditya Kant, Petale, Mahendra, Dutta, Surabhi, Bagul, Mithilesh

Comparative Study of ADC12, A356, and AlSi10Mg Alloys in Sand Casting of EV Battery Housing

2026-26-0296

1/16/2026

This research investigates the applicability of ADC12 aluminum alloy in sand casting processes and compares its casting behavior and performance with that of conventionally sand-cast alloys such as A356 and AlSi10Mg. ADC12 is primarily utilized in high-pressure die casting (HPDC) and low-pressure die casting (LPDC) due to its excellent castability, pressure tightness, and favorable mechanical properties in thin-walled components. However, its use in sand casting is minimal globally, primarily due to the alloy’s high silicon and iron content, which can lead to poor feeding characteristics, increased porosity, and structural non-uniformity in non-pressurized molds. In this study, 3 mm thick test castings were produced using conventional sand casting methods, with particular attention to mold and core design to simulate challenging flow and solidification conditions. Comparative castings of A356 and AlSi10Mg were also produced under identical conditions to establish performance baselines. The objective was to evaluate the filling behavior, solidification characteristics, and final casting quality of ADC12 in sand molds, and to determine its potential for use in applications where die casting is not viable. A comprehensive evaluation was conducted covering key casting parameters: Fluidity and mold filling behavior (evaluated through flow pattern simulations and casting trials) Casting defects and internal integrity (analyzed using real-time X-ray radiography and defect quantification techniques). Density Index (DI) to assess gas entrapment and hydrogen porosity. Mechanical properties, including tensile strength, yield strength, elongation, and hardness (tested according to ASTM standards). Microstructural characterization via optical microscopy and SEM/EDS to examine grain structure, silicon morphology, and intermetallic phases. Fractography of failed tensile specimens to understand failure modes and defect influence. Preliminary results indicate that although ADC12 exhibits higher susceptibility to porosity and reduced ductility in sand cast form compared to A356 and AlSi10Mg, it is still capable of producing structurally acceptable components with optimized gating and venting designs. The study contributes new insights into the adaptability of ADC12 for sand casting, expands the material selection range for low-volume or prototype production scenarios, and provides a technical basis for further optimization of casting parameters to enhance the performance of ADC12 in sand mold applications.

Subramani, Rajesh, Singh, Gajendra, Doddamani, Mrityunjay

Alternative to PFAS Ban: Impact on the Systems and Implementation Challenges

2025-36-0102

12/18/2025

In early of 2023 the European Union began the process of banning the so-called Per- and polyfluoroalkyl substances, with a total elimination forecast for 2035. Currently, the refrigerant gas used by automakers is the R1234yf, a substitute for the R134a as a refrigerant with zero degree of ozone layer destruction, developed to meet the European directive 2006/40/EC that came into force in 2011. It requires all new car platforms for sale on the continent to use a refrigerant in their air-conditioning system with a Global Warming Potential below 150. The alternatives studies for the replacement of R1234yf are R744 (CO2) and R290 (Propane). The first is characterized by being a non-flammable gas and has a working pressure of 6 to 12 times higher than the current one. The second has the characteristic of having working pressure similar to R1234yf, but it is a highly flammable gas. This work focuses on the analysis of the two alternative gases to R1234yf, exploring their characteristics, detailing their impact on the systems, and discussing the challenges for the implementation of each of them.

Ariza, Valquíria Rezende, Erberelli, Diego Pivatto, Silva, Pedro Henrique Moraes da, Miyauchi, Edison Tsutomu

Study on the Performance of High-Pressure Oxygen Cylinder Oxygen Supplemental System in Civil Aircraft Lavatories Based on Airworthiness Oxygen Requirements

2025-99-0307

12/17/2025

This paper focuses on the performance of the high-pressure oxygen cylinder oxygen supplemental system in the lavatory of civil aircraft. Due to the potential safety hazards of chemical oxygen generators in the lavatory, high-pressure gaseous oxygen cylinders are used instead. Through theoretical and study, the influence of the orifice on the oxygen flow rate is thoroughly investigated. Based on relevant principles, the calculation method of the gas flow characteristics in the orifice is determined. Considering the high initial pressure of the oxygen cylinder, the supersonic flow condition within approximately 20 minutes is mainly considered. The Simulink is used to simulate the system flow rate under different temperatures during cabin depressurization. Experimental verification shows that the oxygen flow rate under different temperatures meets the minimum oxygen demand, and the simulation results are highly consistent with the experimental results, indicating that the simulation accuracy meets the airworthiness standards and provides a strong basis for the design and optimization of the system.

Wan, Shuting, Lei, Mingjun, Yu, Xiaoying

Entangled-Photon Pairs Secure Optical Communications

TBMG-54294

12/1/2025

NASA’s Glenn Research Center has developed a method of using entangled-photon pairs to produce highly secure mobile communications that require mere milliwatts of power. Conventional gas Argon-ion laser sources are too large, expensive, and power-intensive to use in portable applications. By contrast, Glenn’s patented optical quantum communication method produces entangled-photon pairs approximately a million times more efficiently than conventional sources, in a system that is small and light enough to be portable.

Automation: How Custom Motion Control Transforms Medical Equipment Design

TBMG-54340

12/1/2025

In today’s medical equipment market, reliability is not a luxury — it is a necessity. Every adjustment, every movement, and every interaction with the equipment must be performed flawlessly to ensure patient safety, caregiver efficiency, and long-term service life. Behind this design and precision are highly engineered motion control components, such as gas springs, electric linear actuators, and dampers, that ensure safe, ergonomic operation of medical equipment across a wide range of healthcare applications.

Low-Power Hydrogen Sensor Detects Leaks in an Instant

TBMG-53902

10/1/2025

Hydrogen is a clean-burning fuel that could help to replace fossil fuels in transportation, the chemicals industry, and many other sectors. However, hydrogen is also an explosive gas, so it is essential to have safety systems that can reliably detect leaks in a variety of circumstances.

Enabling Near-Zero Emissions and Superior Efficiency in Large-Bore, Medium-Speed Engines with a Hydrogen-Argon Power Cycle

2025-24-0001

9/7/2025

Combustion engines operating on a hydrogen-argon power cycle (H-APC) offer potential for superior thermal efficiency with true zero exhaust emissions. The high specific heat ratio of argon allows extrapolation of the theoretical efficiency of the Otto cycle to almost 90%. However, this potential is significantly constrained by challenges in combustion control, excessive thermal loading, and system integration, particularly regarding argon recovery. This study investigates these trade-offs, within the context of real-world engine-based peaking power plants. An experimentally validated 1D-simulation model of a prototype Wärtsilä 20 DF engine serves as reference for analysis of a retrofit incorporating a closed-loop argon cycle, with dedicated H₂ and O2 injectors, a water condenser and water separator. Engine performance is evaluated at reference operating point of 75% load, considering pre-ignition, peak pressure and exhaust temperature constraints, condenser limitations, and impurity accumulation. Argon emerges as the best monoatomic gas for H-APC. Helium, the second-best candidate, offers superior thermal conductivity and specific heat, but its low density and molecular weight reduce power output. A 90% argon and 10% oxygen mixture offers the optimal trade-off between power output, efficiency, and durability. A compression ratio of 11.90:1 ensures stable combustion within design constraints, while stoichiometric operation and condenser inlet pressure of 3.23 bar enhances performance, achieving the best indicated gross efficiency of 59.10%. This is over 10 percentage points better than the reference engine at 75% load. Nevertheless, practical implementation is limited by pumping losses in a packaging-optimized argon-path layout, reducing extractable efficiency to 56.70%. Furthermore, just 2% impurities in fuel/oxidizer stream causes progressive efficiency decline, falling below the reference threshold after approximately 10 minutes of operation. This highlights the necessity of a membrane-based separator and system volume optimization. The findings establish a validated computational framework for optimizing closed-loop hydrogen combustion and provide valuable insights for progressing demonstrator development.

Ahammed, Sajid, Ahmad, Zeeshan, Mahmoudzadeh Andwari, Amin, Kakoee, Alireza, Hyvonen, Jari, Mikulski, Maciej

Experimental Investigation of the Comparison between Helium and Hydrogen Jets Exiting a DI Outward-Opening Injector via Schlieren Technique

2025-24-0068

9/7/2025

This paper deals with the hydrogen-to-helium jets comparison within the framework of the assessment of helium as a potential hydrogen surrogate. The comparison is centred on the assessment of the combined action of pressure ratio with gas properties on the dynamics of the jet exiting an outward-opening injector. The shots are performed at injection pressures and backpressures ranging from 21 to 36 bar and from 1.2 to 5 bar, respectively. The Schlieren technique is deployed to capture the jets images. The study demonstrates that at certain pressure ratios helium is an appealing solution bridging the lab safety with fidelity to hydrogen-like jet behaviour. Decreasing pressure ratio minimizes the hydrogen-to-helium difference in axial penetration and area, enabling helium to yield a hydrogen-like development. The findings underscore the impact of the pressure ratio on how the gas properties, such as density and diffusivity, dictate the evolution of the axial propagation and area, respectively.

Coratella, Carlo, Tinchon, Alexis, Hespel, Camille, Dober, Gavin, Foucher, Fabrice

Electronics-Free 3D-Printed Robots

TBMG-53537

8/1/2025

Imagine a robot that can walk, without electronics, and only with the addition of a cartridge of compressed gas, right off the 3D printer. It can also be printed in one go, from one material.

In Situ Observation of Different Soot Layers in a Model Filter Channel during Its Regeneration

2025-01-0312

7/2/2025

In order to comply with increasingly stringent emission regulations and ensure clean air, wall-flow particulate filters are predominantly used in exhaust gas aftertreatment systems of combustion engines to remove reactive soot and inert ash particles from exhaust gases. These filters consist of parallel porous channels with alternately closed ends, effectively separating particles by forming a layer on the filter surface. However, the accumulated particulate layer increases the pressure drop across the filter, requiring periodic filter regeneration. During regeneration, soot oxidation breaks up the particulate layer, while resuspension and transport of individual agglomerates can occur. These phenomena are influenced by gas temperature and velocity, as well as by the dispersity and reactivity of the soot particles. Renewable and biomass based fuels can produce different types of soot with different reactivities and dispersities. Therefore, this study focuses on the influences of soot dispersity and reactivity by varying the reactive particle system. A model wall-flow filter channel is used for the investigation, enabling the observation of the layer break-up and detachment of particle structures from the filter surface over the entire channel length using a high-speed camera operating at 1000 fps. Recordings reveal significant differences in the behavior of the different soot types. Image analysis provides insights into the visual layer break-up, evolution of structure sizes, detachment dynamics, agglomerate velocities, and the spatial and temporal distribution of detachment events. General parameters, such as regeneration time and pressure drop, further characterize the regeneration process. The results provide insights into the detachment and rearrangement behavior of reactive particle structures with varying dispersities and reactivities in wall-flow filters, demonstrating that these characteristics can significantly influence the regeneration process.

Desens, Ole, Hagen, Fabian P., Meyer, Jörg, Dittler, Achim

Long-Lasting 3D Printed Wearable Transforms Health Monitoring

TBMG-53439

7/1/2025

A long-lasting, 3D-printed, adhesive-free wearable provides a more comprehensive picture of a user’s physiological state. The device, which measures water vapor and skin emissions of gases, continuously tracks and logs physiological data associated with dehydration, metabolic shifts, and stress levels.

Investigating Lubricants Base Oils Reactivity in Ammonia Engines via Accelerated Aging

2025-01-0240

6/16/2025

As a carbon-free molecule, ammonia is more and more considered as a relevant fuel for long distance and off-road applications. However, this gas has different combustion characteristics compared to conventional fuels, challenging the suitability of lubricants to such engines. In this work, the evolution of lubricants under conditions mimicking ammonia combustion was assessed. Mineral and polyester lubricant base oils were exposed to oxygen, nitrogen oxides, and ammonia in a pressurized reactor under stirring. Oil aliquots were sampled at regular intervals, and characterized using Fourier Transform Infrared Spectroscopy (FTIR), viscosity and total oxygen and nitrogen contents measurements. Exposure to air containing nitrogen oxides resulted in quicker accumulation of oxidation products compared to neat air, for both the mineral and complex polyester base oil. Besides, exposure to gaseous ammonia in air resulted in a slower oxidation rate for both oils, compared to neat air. A global measurement of the total nitrogen content after 2 h showed a significant increase for both oils. Under similar conditions, the total nitrogen content of the polyester base oil was higher than the mineral oil, indicating a higher affinity of the ammonia with this matrix. Chromatograms obtained with a Gas Chromatography (GC) column associated to a Nitrogen Chemiluminescence Detector (NCD) showed that nitrogen speciation evolved from nitrogen contained in very light molecules, likely dissolved ammonia, to molecular nitrogen distributed across the entire range of hydrocarbon chain lengths. This demonstrates that ammonia reacted with the base oils and their degradation products. Two-dimensional gas chromatography and mass spectrometry will be performed in the upcoming months to identify these new kinds of degradation products. This study paves the way towards a better understanding of oil reactivity when exposed to ammonia combustion byproducts, including outcomes on engine operation and emissions of pollutants.

Doncoeur, Carole, Giarracca, Lucia, Cologon, Perrine, Rousselle, Christine

3D-Printed Porous Media Combined with Biomimetic Distributor for Small-Scale Polymer Electrolyte Membrane Fuel Cells

2025-01-0196

6/16/2025

This study presents a novel biomimetic flow-field concept that integrates a triply periodic minimal surface (TPMS) porous architectures with a hierarchical leaf-vein-inspired distribution zone, fabricated through 3D printing. By mimicking natural transport systems, the proposed design enhances oxygen delivery and water removal in proton exchange membrane fuel cells (PEMFCs). The results showed that I-FF and G-FF significantly improved mass transport and water management compared to conventional CPFF. The integrated design I-FF-LDZ achieves up to 32% improvement in power density at 1.85 A/cm2@0.4 V and delays the onset of mass transport losses. The study also reveals that optimizing the volume fraction Vf significantly affects gas penetration, with lower Vf (30%) improving performance in the mass-limited region. These findings underscore the promise of nature-inspired, 3D-printed flow-field architectures in overcoming key transport limitations and advancing the scalability of next-generation PEMFC systems.

Ho-Van, Phuc, Lim, Ocktaeck

Morphology Experiment of Icing Effect on Spray Propagation

2025-01-0222

6/16/2025

The working conditions of combustion systems have been going extreme under the desire of human beings exploring the unknown. Cold environments can be a significant impact on the spraying of fuel not only by changing the fuel properties including viscosity and surface tension, but also by freezing the parts. In the present study, methanol spray from a commercial injector is studied via high-speed imaging, with the liquid fuel being frozen to sub-zero degrees at the injector tip. It is observed that water components from the environment will freeze at the injector tip, creating crystal structures on the surface. During the injection, the ice components will be flushed by the liquid, and the spray morphology of the starting cycle will be strongly altered, resulting in wider spray angles, much shorter penetrations, and particle structures can be observed in the downstream of the flow field. The results of the experiment provide a clear view and quantified evaluation of the freezing impact on spray development from practical injectors, and gives a sketch of the most extreme condition of the fuel spray before the valve is chilled to the bone and unable to open.

Zeng, Tingxi, Wang, Shangning, Zhang, Yijia, Hung, David, Xu, Min

Cislunar Space Exploration: Next Frontier for Propulsion Advancements

TBMG-53029

5/1/2025

The race is on for leadership in cislunar space, considered a gateway to the future of space exploration. Yet operating in this domain introduces unique challenges for propulsion systems. In contrast to low-Earth orbit (LEO), the cislunar environment requires higher precision propulsion solutions; these are necessary to enable rapid and accurate maneuvering of spacecraft and long-term sustainability. Propellants like hydrazine and nitrogen tetroxide offer the high energy density required for cislunar missions, but they must be handled very differently from the inert, non-reactive gases at play in LEO systems.

Numerical Studies on the Relation between the Multiple Auto-Ignition and Pressure Wave in the Premixed Charge

2024-32-0079

4/18/2025

The relation between the multiple auto-ignition in the premixed charge with fuel concentration distribution and associated pressure wave are numerically investigated. This study assumes that the auto-ignition phenomenon in the end-gas of PCCI combustion, a next-generation combustion method which is expected to achieve both low fuel consumption and low emissions at a high level. Detailed numerical analysis considering the elementary chemical reactions of the compressible reacting fluid flow described in the one-dimensional coordinate system with high spatial and time resolution was performed to clarify the detailed phenomena of the onset of the multiple auto-ignition and the pressure wave propagation in the gas.

Iizumi, Kota, Yoshida, Kenji

Development of NOx Storage Catalyst and Investigation of Deterioration Mechanism for Small Powertrains

2024-32-0097

4/18/2025

In response to the evolving landscape of exhaust gas regulations for small powertrains, reducing NOx emission is increasingly important. This study deeply investigated the feasibility of a NOx storage catalyst (NSC) containing cerium oxide (CeO2) and barium oxide (BaO) for reducing NOx emission. The key functions, NOx storage and reduction performances were evaluated, and deterioration mechanisms were explored through performance evaluations and physical property analyses. The findings revealed a strong correlation between the size of CeO2 crystals and NOx storage performance at low temperature, such as those encountered during city driving conditions. Conversely, at high temperature, such as those during highway driving conditions, NOx storage performance correlated well with sulfur deposition, suggesting that the formation of barium sulfate (BaSO4) contributes to the deactivation. This experiment also showed a strong correlation between NOx reduction performance and BaSO4 formation. A new aging method that can simulate both thermal and sulfur deterioration was established based on these findings. This method effectively reflects field aging conditions. A new NSC based on the concept of resisting this newly established aging method showed significantly improved performance in both NOx storage and reduction. Despite an increase in the amount of barium components compared to the conventional NSC, high performance was maintained after sulfur poisoning. In the case of the new NSC, it was found that weakly basic chemical introduced as a sulfur scavenger suppresses the formation of BaSO4. This new NSC concept is expected to be leveraged in a wide range of vehicles including small powertrains, to achieve robust performance.

Nakano, Fumiya, Koito, Yusuke

Detailed Approach for Pre-Chamber Heat Release Analysis for the HSASI Pre-Chamber Spark Plug Using a Pressure Sensor Glow Plug

2024-32-0063

4/18/2025

The hot surface-assisted spark ignition (HSASI) pre-chamber spark plug, which was developed at the Karlsruhe University of Applied Sciences, increases the dilution limit with excess air and the tolerance to residual gas in the pre-chamber compared to a conventional passive pre-chamber spark plug. In this study, the conventional glow plug which is integrated in the pre-chamber of the HSASI pre-chamber spark plug was replaced by a pressure sensor glow plug (PSG) from BERU. This allows for a detailed combustion analysis in the pre-chamber. The signal of the PSG was validated with a piezoelectric cylinder pressure sensor and a method to analyse the pre-chamber heat release was introduced. Experimental investigations were carried out on a single-cylinder gasoline engine. A series of operating points diluted with excess air and a variation in load were conducted. The gas flow rate through the orifices of the pre-chamber was calculated from the pressure difference between the pre-chamber and the main chamber. Furthermore, the momentum and the enthalpy flow of the gas jets leaving the pre-chamber were calculated to determine their influence on the heat release in the main combustion chamber. The HSASI operation was compared with a passive pre-chamber spark plug. It shows a faster heat release inside the pre-chamber which leads to a higher enthalpy and momentum of the gas jets leaving the pre-chamber. This results in a faster flame development in the cylinder and less cycle-to-cycle variations.

Holzberger, Sascha, Kettner, Maurice, Kirchberger, Roland

Market Research & Analysis of Failures due to Environmental Gases in Automotive Electronics and Integration of Learnings in Development Testing

2025-01-8255

4/1/2025

Automotive industry is growing rapidly with innovations leading to increase in new features and improving the Quality of vehicles. These new components are developed with the available design standards across global OEMs. This Quality research paper aims to address the need of revision of design standards due to environmental factors prevailing in India. With the increase towards autonomous mobility, the number of electronics is also increasing, and this involves hardware & software evaluation. The hardware testing is a point of concern due to increase in the failure rate from the markets. Environment changes are very much evident with the growing economies and OEMs are developing the components with innovation, but if the basic design standards are not revised in parallel with the changing environment, the issues will continue to trouble the end customers. The failed cases data received from across the country was analyzed and observed that the cases are majorly reported from urban localities established near to the city drains. The lab report of failed components shows a chemical reaction with environment gases leading to conductivity issue. Based on the study, Quality research was done around the localities to understand the gaseous concentration. The data shows 50X high gaseous concentration compared to the development standard and the same was then simulated. This data gave us a new perspective to revise the development testing standards & can also enable OEMs to better understand the market problems & take action for environment factors. With the ever-changing environmental conditions & expansion of automotive market, the possibilities of such impacts are limitless & this approach can be used to further study the automotive issues due to other factors like Dust, Water, Temperature, Humidity, Snow, Insects etc.

Marwah, Ramnik, Pyasi, Praveen, Bindra, Ritesh, Garg, Vipin

Development of Dehydrated Kusum Oil as a Potential Bio-Lubricant

2025-01-8312

4/1/2025

Depletion of petroleum crude oil and its environmental impacts challenge future generations. Vegetable oils provide a sustainable alternative with benefits like anti-wear properties, biodegradability, and renewability. Kusum oil's ability to lower carbon emissions significantly and promote sustainable industrial practices highlights its potential as a viable green alternative. This research paper presents a comprehensive and comparative analysis of a sustainable, environmentally friendly bio-lubricant and nonedible vegetable oil like Kusum oil. Bio-lubricant is produced by transesterification followed by epoxidation, which is known as epoxidized kusum oil lubricant or dehydrated kusum oil (DKO). The process of epoxidation significantly enhances the properties of Kusum oil, making it a promising alternative to conventional lubricants. It is compared with a widely used conventional mineral oil lubricant like SAE10W40. DKO exhibits comparable density, viscosity index, pour point, and flash point with SAE10W40 and found satisfactory. Subsequently, FTIR (Fourier Transform Infrared Spectroscopy) and GC (Gas Chromatography) are also used to characterize the chemical composition of DKO, and the results are comparable with SAE10W40. By introducing epoxy groups into the unsaturated fatty acids of Kusum oil, epoxidation increases the oil's oxidative stability, making it more resistant to degradation at high temperatures, which is verified with the Thermo Gravimetric Analysis (TGA). It reveals that the bio-lubricant is thermally stable up to 250°C, with significant decomposition occurring between 250°C and 450°C. The epoxidized kusum oil with 0.2wt. % MWCNT significantly improves its anti-wear characteristics, leading to a reduction in wear volume when compared to both SAE10W40. This highlights its promise as a viable and eco-friendly substitute lubricant for mechanical uses. This comparison underscores the importance of epoxidized kusum oil bio-lubricant, and it provides a new direction for similar research and development in lubricants, aiming to balance performance with environmental responsibility.

Prabhakaran, J, Pali, Harveer Singh, Singh, Nishant K.

Capillary Transport Analysis in Macro-Homogeneous Diffusion Media of PEM Fuel Cells

2025-01-8546

4/1/2025

The interplay of electrochemistry, two-phase flow, and heat transfer generates complex transport phenomena within the porous materials of fuel cells that are not yet fully understood. This lack of comprehensive understanding complicates the modeling of liquid water transport, which is critical because the hydration of the polymer electrolyte membrane significantly impacts the cell performance. The liquid water transport mechanisms in porous media can be explained by capillary force, hydraulic permeation and gravity effects, as well as water condensation and evaporation. In general, the liquid water transport is mainly driven by the capillary force, while body forces, such as gravity, do not significantly affect its momentum. Due to limited experimental data on capillary pressure and saturation in gas diffusion media, the Leverett approach has been widely used for modeling liquid water transport in PEMFCs. The Leverett approach is a polynomial fitting of capillary pressure data for water imbibition in unconsolidated sand packs. Due to its nature, this approach may not accurately predict capillary pressure in gas diffusion media. Fuel cell GDM materials, naturally hydrophilic, are typically coated with a nonwetting polymer like polytetrafluoroethylene to create hydrophobic surfaces and pores. The resulting nature of GDM materials, with intermediate wettability due to the coexistence of hydrophilic and hydrophobic pore spaces, complicates transport phenomena. Consequently, the applicability of the traditional Leverett approach is questionable. This work focuses on capillary transport within PEMFCs, highlighting key experimental and modeling approaches for predicting the capillary pressure-saturation relationship. Starting from the Leverett function, improved models have been proposed and are here implemented in a 3D-CFD model. This research provides an overview of key experimental and theoretical developments in understanding capillarity in PEMFCs. Furthermore, it implements selected capillary pressure correlations in a 3D-CFD model to evaluate their performance in simulating water transport within the porous media, providing guidelines for their use in large-scale models.

Marra, Carmine, Croci, Federico, Fontanesi, Stefano, Berni, Fabio, D'Adamo, Alessandro

Characterization of Spark Ignition Energy Transfer at Different Phases Using Pressure-Rise Calorimetry

2025-01-8402

4/1/2025

The paper presents novel studies on the electrical-to-thermal energy deposition to gas at different phases of a spark. The experiments utilized a 10.9 milliliter custom-built spark calorimeter. The energy transfer efficiencies across spark phases—breakdown+arc, and glow are quantified, emphasizing their importances in ensuring robust ignition. An AC capacitive ignition system was considered in the experiments. The spark plugs used in the experiments were of dual-nickel standard J-gap design of a fixed electrode gap. Test results show the breakdown+arc phases are highly efficient in converting electrical to thermal energy, crucial for ignition. The glow phase, offering control flexibility, is found to be less effective in energy transfer from spark to gas. In addition, a maximum threshold for both glow current and duration is found. Exceeding the threshold reduces the net energy deposition to the gas, indicating an increase in thermal energy losses, primarily to the spark plug electrodes. Furthermore, a positive relationship between gas pressure and glow phase efficiency is established. The energy transfer to the gas during the glow phase is found to improve with the increase in gas pressure. Based on the findings, an optimal ignition control strategy is proposed for both biogas and hydrogen fueled spark ignited internal combustion engines (SI-ICEs). It aims to maximize energy transfer to gas and reduce heat losses to spark plug electrodes. Using this approach may extend spark plug life in biogas engines and lower the risk of pre-ignition from overheated spark plug electrodes in hydrogen engines.

Saha, Anupam, Tunestal, Per, Aengeby, Jakob, Andersson, Oivind

Fundamental Science on Oxygen Storage Capacity of Cerium Complex Oxides for Advanced On-Board Diagnostics (2) Quantitative Observation of Oxygen Released from Cerium Complex Oxides

2025-01-8476

4/1/2025

In order to comply with the tightening of global regulations on automobile exhaust gas, further improvements to exhaust gas control catalysts and upgrades to on-board diagnostics (OBD) systems must be made. Currently, oxygen storage capacity (OSC) is monitored by front and rear sensors before and after the catalyst, and deterioration is judged by a decrease in OSC, but it is possible that catalyst deterioration may cause the rear sensor to detect gas that has not been sufficiently purified. It is important to observe the activity changes when the catalyst deteriorates in more detail and to gain a deeper understanding of the catalyst mechanism in order to create guidelines for future catalyst development. In this study, we used a μ-TG (micro thermogravimetric balance) to analyze in detail how differences in design parameters such as the type of precious metal, detection temperature, and mileage (degree of deterioration) affect the OSC rate in addition to the OSC of the ceria-based composite oxide of the entire catalyst. It was found that CZY has better durability in terms of both OSC rate and amount than CZ. Furthermore, by comparing the results of experiments using time-resolved dispersive X-ray absorption fine structure (DXAFS) using synchrotron radiation, the reduction behavior of ceria was analyzed in more detail.

Hamada, Shota, Uegaki, Shinya, Tanabe, Hidetaka, Nakayama, Tomohito, Jinjo, Itsuki, Kurono, Seita, Oishi, Shunsuke, Narita, Keiichi, Onishi, Tetsuro, Yasuda, Kazuya, Matsumura, Daiju, Tanaka, Hirohisa

Leveraging the Plasma Pen for Solving Complex Adhesion Challenges

TBMG-52632

3/1/2025

Plasma is a state of matter, like a solid, liquid, or gas. When sufficient energy is applied to a gas, it becomes ionized, transitioning into the plasma state. With precise application and control, plasma can alter surface properties of a metal or plastic part without compromising the underlying material.

Preparation of Copper Antimony Sulfide Thin Film Solar Cells by Chemical Synthesis

2025-28-0117

2/7/2025

Copper Antimony Sulfide (CuSbS2) is a promising ternary semiconductor for use as an absorber layer in third-generation thin film heterojunction solar cells. This newly developed optoelectronic material offers a viable alternative to cadmium telluride (CdTe) and copper indium gallium di-selenide (Cu(In,Ga)Se2) due to its composition of inexpensive, readily available, and non-toxic elements. These films were successfully produced at an optimal substrate temperature of 533 K using the conventional spray technique. X-ray diffraction and Raman studies confirm that the films exhibit a chalcostibite structure. Characterization studies reveal that the films possess lattice parameters of a = 0.60 nm, b = 0.38 nm, and c = 1.45 nm, with an absorption coefficient of 105 cm-1 and a band gap of 1.50 eV. Notably, the films exhibit p-type conductivity. All of these studies confirm that CuSbS2 is an excellent choice for the absorber layer in solar cell applications. An attempt was made in this study to improve the crystallinity of the CuSbS2 films by different experimental conditions. (i) CuSbS2 films have been fabricated using two different carrier gases (air and nitrogen) via chemical spray pyrolytic technique. (ii) To enhance the crystallinity of these films, spray pyrolytic films have been kept on the hot plate at optimal substrate temperature for about 15 minutes. Subsequently, a CuSbS2 solar cell is developed entirely through the non-vacuum method. The absorber layer is fabricated by using the spray pyrolytic method. A n-CdS buffer layer is successfully deposited via the chemical bath technique. The cell’s efficiency increased from 0.488% to 0.54% when the absorber layer in the solar cell was left on hot substrates for about 15 minutes following the pyrolytic reaction. The study discusses how these techniques contribute to improving the efficiency of the solar cell parameters.

Kumar, YB Kishore, Yb, Kiran, Tarigonda, Hariprasad, Reddy M, Surya Sekhar

Cryogenic Flux Capacitor

TBMG-52477

2/1/2025

NASA's Cryogenic Flux Capacitor (CFC) capitalizes on the energy storage capacity of liquefied gases. By exploiting a unique attribute of nano-porous materials, aerogel in this case, fluid commodities such as oxygen, hydrogen, methane, etc. can be stored in a molecular surface-adsorbed state. This cryogenic fluid can be stored at low to moderate pressure densities, on par with liquid, and then quickly converted to a gas, when the need arises. This solution reduces both safety-related logistics issues and the limitations of complex storage systems.

Pressure-Dependent Nonlinearities of a Compact Hydropneumatic Strut with Integrated Gas–Oil Chamber

10-09-01-0008

1/24/2025

Hydropneumatic Struts (HPS) are widely implemented in automobile, aerospace, and construction industries, mainly for the purpose of vibration and shock absorption. The HPS design with integrated gas–oil chamber is relatively more compact and robust, while mixing gas and oil inside the HPS generates gas–oil emulsion and more nonlinearities. This study formulated a nonlinear analytical model of the compact HPS with gas–oil emulsion, considering the real gas law and pressure-dependent LuGre friction model. The polytropic version of the van der Waals (vdW) method for real gas is applied to represent the thermodynamic behavior of nitrogen. The experimental data were collected at a near temperature of 30°C with three charging pressures under excitations in the frequency range of 0.5–6 Hz, considering two flow connection configurations between chambers as one- and two-bleed orifice. The nonlinear behavior of the gas volume fraction of the emulsion was identified based on peak strut velocity and charge pressure. Discharge coefficients of bleed and check valves were determined as a function of the instantaneous pressure difference between chambers. The parameters of the pressure-dependent LuGre model, such as the stiction force and Coulomb force apart from stiffness and damping coefficient of bristle deflection, were also investigated considering the effect of pressure variation. Compared to the generally used ideal gas and models, the proposed model considerably improved the prediction accuracy of the total force and pressures of HPS, with normalized root-mean-square deviations of about 8%.

Seifi, Abolfazl, Yao, Yumeng, Yin, Yuming, Moore, Masih, Rakheja, Subhash

Study of Functional Behaviour of Cast Magnesium Alloy with Zirconium Addition

2024-01-5206

12/10/2024

Magnesium is the lightest material than aluminium and has a better specific strength, which is utilized for weight management applications. This research developed the magnesium (Mg) matrix with 0.1, 0.2, 0.3, and 0.5 percentages in weight (wt%) of zirconium (Zr) particles (grain refinement agent) via the squeeze cast technique. The argon inert gas is limit oxidation during the melting of Mg. The influence of Zr on the functional properties of Mg is studied and related to monolithic Mg without the Zr phase. The microstructural analysis provides the Zr particles are dispersed uniformly in the Mg matrix and exposed to superior mechanical properties. The Mg processed with 0.5 wt% of Zr offered maximum hardness, ultimate tensile strength, and elongation percentage, which are 53, 48.8, and 43.5 % better than the values of monolithic Mg. Besides, the optimum Mg refining with 0.5 wt% Zr microstructure is detailed with EDS and conforms to the contribution of Zr. This is used for automotive structural (frame) applications.

Venkatesh, R., Manivannan, S., Das, A. Daniel, Mohanavel, Vinayagam, Soudagar, Manzoore Elahi Mohammad

Autonomous Mobile Robot for Gas Leak Localization

2024-01-5226

12/10/2024

LIDAR-based autonomous mobile robots (AMRs) are gradually being used for gas detection in industries. They detect tiny changes in the composition of the environment in indoor areas that is too risky for humans, making it ideal for the detection of gases. This current work focusses on the basic aspect of gas detection and avoiding unwanted accidents in industrial sectors by using an AMR with LIDAR sensor capable of autonomous navigation and MQ2 a gas detection sensor for identifying the leakages including toxic and explosive gases, and can alert the necessary personnel in real-time by using simultaneous localization and mapping (SLAM) algorithm and gas distribution mapping (GDM). GDM in accordance with SLAM algorithm directs the robot towards the leakage point immediately thereby avoiding accidents. Raspberry Pi 4 is used for efficient data processing and hardware part accomplished with PGM45775 DC motor for movements with 2D LIDAR allowing 360° mapping. The adoption of LIDAR-based AMRs for gas detection is expected to increase in the future, as more industries realize the benefits of this technology.

Feroz Ali, L., Madhankumar, S., Hariush, V.C., Jahath Pranav, R., Jayadeep, J., Jeffrey, S.

Investigation on Mechanical and Metallurgical Characterization of Micro-Alloyed Steel Produced by Friction Stir Welding (FSW)

2024-01-5203

12/10/2024

This research investigates the impact of friction stir welding (FSW) used to join micro-alloyed steel, on the material and its mechanical characteristics. FSW increases the metallurgical and mechanical qualities of joints made from micro-alloyed steel. However, Friction Stir Welding has produced only modest improvements in connecting steels. Automobile chassis, offshore platforms, oil and gas pipelines, mining, shipbuilding and railroad carriages, pressure vessels, bridges, and storage tanks are just some of the many places and find micro-alloyed steels employed. Frictional heat and tool movement over the joint cause micro defects occurred. Tungsten carbide tools are used in this investigation. Welding shares the same process characteristics, such as the tool's rotating speed (900 rpm) and axial force (10 kN). The table's traverse speed options are available, including 50 mm/min, 60 mm/min, and 70 mm/min. Vickers microhardness testing machines and tensile testing machines are used to perform mechanical characterizations such as hardness testing and tensile testing, respectively. Charpy testing was used to analyze the impact energy released during the fracture of the welded joint. The Scanning Electron Microscope (SEM) and Optical Microscope are used for metallurgical characterizations such as microstructure and tensile fracture research. DMR-249A is low-carbon micro-alloyed steel, and it is a far better grade than the multiple grades that have previously been used for naval and other industrial uses like shipbuilding, railway car construction, etc.

Rajan, C. Sakthi, Kumar, N. Mathan, Kumar, K. Vetrivel, Kannan, S., Soundararajan, S.

Synthesis and Characterization of Advanced Multi Nanoparticle Based Nanofluid Stabilized by Surfactants

2024-28-0139

12/5/2024

Recently, there has been a growing emphasis on Thermal Management Systems (TMS) for Lithium-ion battery packs due to safety concerns related to fire risks when temperatures exceed operating limits. Elevated temperatures accelerate electrochemical reactions, leading to cell degradation and reduced electronic system performance. These conditions can cause localized hotspots and hinder heat dissipation, increasing the risk of thermal runaway due to high temperatures, flammable gases, and heat-producing reactions. To tackle these issues, many automotive manufacturers employ indirect liquid cooling techniques to maintain battery pack and electronic system temperatures within safe limits. Engineered nanofluids, particularly those containing multi-nanoparticles dispersed in water and ethylene glycol, are being explored to enhance electrical safety in case of accidental exposure to electrical systems in EVs. This paper focuses on the experimental characterization of nanofluid containing Titanium Dioxide (TiO2), Copper Oxide (CuO), Aluminum Oxide (Al2O3), and Graphene Oxide (GO) nanoparticles stabilized with Triton X-100 and Sodium Dodecyl Sulphate (SDS) surfactants. The study examines the formulation and characterization of these nanofluids for equilibrium boiling point, kinematic viscosity, density, and electrical conductivity. The findings underscore the importance of advanced technologies in ensuring the reliability, efficiency & safety of Lithium-ion batteries. By improving electrical characteristics, these advanced nanofluids can mitigate risks associated with overheating, thereby enhancing overall safety and performance.

Nahalde, Sujay, Honrao, Gaurav, More, Hemant

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