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

Holzberger, Sascha, Kettner, Maurice, Kirchberger, Roland

Experimental Investigation of n-C7H16/Ethanol Blended Fuels on Auto-ignition and Flame Propagation in High Temperature/Pressure Constant-Volume Combustion Vessel

2024-32-0050

04/18/2025

This study aims to investigate the effect of ethanol blends on flame propagation and auto-ignition under high pressure and high temperature conditions. Experimental investigations are conducted using n-C7H16 / ethanol blends at various blending ratios (0, 5, 10, 20, 40, 70, and 100 vol%). The blends are premixed with air at stoichiometric ratios and ignited centrally in a cylindrical constant-volume combustion chamber (20-mm inner diameter, 80-mm long) under elevated temperature (500 K) and pressure (1.0 MPa) conditions. The results show that auto-ignition occurs at an ethanol blend ratio of 10% or less and ceases above 20%. Increasing the ethanol blend to 70% results in a slight change in flame propagation speed, with a noticeable delay at 100%. The pressure measurements show a peak of about 5.6 MPa at a blend ratio of 5%, which gradually decreases with increasing ratios. High-pass filtering reveals the maximum pressure fluctuation amplitude at the 5% blend ratio, indicating increased

Tateishi, Tokua, Yamaguchi, Riki, Shimokuri, Daisuke, Terashima, Hiroshi, Hara, Takaya, Honda, Yuya, Kawano, Michiharu

Study on the Optimal Pre-Chamber Geometry for Active Pre-Chamber Gas Engines

2024-32-0023

04/18/2025

In a pre-chamber engine, fuel in the main-chamber is ignited and combusted by the combustion gas injected from the pre-chamber. Therefore, further fuel dilution is possible and thermal efficiency can be also improved. However, adding a pre-chamber to an engine increases the number of design parameters which have a significant impact on the main combustion and the exhaust gas. Then, in this study, the optimum geometry of the pre-chamber in an active pre-chamber gas engine was investigated. The considered parameters were the volume of pre-chamber, the diameter of a nozzle hole, and the number of nozzle holes. 18 types of pre-chambers with different geometries were prepared. Using these pre-chambers, engine experiments under steady conditions were conducted while changing the conditions such as engine speeds, mean indicated pressure and air excess ratio. Based on the experimental data, neural network models were constructed that predict thermal efficiency, NOx and CO emissions from the

Yasuda, Kotaro, Yamasaki, Yudai, Sako, Takahiro, Takashima, Yoshitane, Suzuki, Kenta

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

2024-32-0079

04/18/2025

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

Experimental Study on Thermo-Catalytic Ammonia Decomposition into Hydrogen

2024-32-0118

04/18/2025

In order to rapidly achieve the goal of global net-zero carbon emissions, ammonia (NH3) has been deemed as a potential alternative fuel, and reforming partial ammonia to hydrogen using engine exhaust waste heat is a promising technology which can improve the combustion performance and reduce the emission of ammonia-fueled engines. However, so far, comprehensive research on the correlation between the reforming characteristic for accessible engineering applications of ammonia catalytic decomposition is not abundant. Moreover, relevant experimental studies are far from sufficient. In this paper, we conducted the experiments of catalytic decomposition of ammonia into hydrogen based on a fixed-bed reactor with Ru-Al2O3 catalysts to study the effects of reaction temperature, gas hour space velocity (GHSV) and reaction pressure on the decomposition characteristics. At the same time, energy flow analysis was carried out to explore the effects of various reaction conditions on system

Li, Ze, Li, Tie, Chen, Run, Li, Shiyan, Zhou, Xinyi, Wang, Ning

Effects of Hydrogen Addition on Spark Knock Suppression under High Engine Speed and Boosted Conditions

2024-32-0108

04/18/2025

The effect of hydrogen addition on spark knock suppression under high engine speed (4800 rpm) was investigated at the intake pressures of 96 kPa and 120 kPa. The experimental results showed that hydrogen addition has a slight effect on advancing the knock limit at 96 kPa, whereas a greater spark knock suppression effect can be achieved by increasing the intake pressure. To elucidate the influences and differences of hydrogen addition on the ignition process under low and high intake pressures, chemical kinetic analyses were performed using a two-zone combustion model. The calculation results showed that the reduction of heat release in the end gas resulting from the consumption of OH radicals by hydrogen can only be achieved at the initial stage of the ignition process. This leads to the smaller knock suppression effect at low intake pressures, where a remarkable heat release at this stage is absent. On the other hand, an increase in intake pressure results in a remarkable heat release

Goto, Jun, Ueno, Yoshito, Kobashi, Yoshimitsu, Shibata, Gen, Ogawa, Hideyuki, Kojima, Kentaro

Aerospace Fluid Systems and Components – Pressure and Temperature Classifications

AS2001B (Current)

04/14/2025

This document establishes the temperature types and pressure classes that are commonly used in aerospace fluid systems. The temperature types and pressure classes are equivalent, but not identical, to the SI units defined in MA2001 (ISO 6771). For exact conversion use NAS 10000.

G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies

Effects of Ambient and Injection Conditions on a High-Pressure Hydrogen Jet for Direct Injection in ICE

2025-01-8466

04/01/2025

The transport sector is responsible for about one third of the global CO2 emissions. To align to the net zero emission scenario, the transportation sector needs the implementation of policies aimed to reduce as much as possible the highly emitting transport options and, at the same time, the use of new technologies to reduce the environmental impact of transport methods whose emissions cannot be entirely eliminated. An exploitable solution for the internal combustion engine (ICE), even in the nearest future, would be to use hydrogen as a fuel in these engines. This is supported by the fact that H2-ICE is the only ICE technology currently capable of meeting the standards imposed by the European Union for 2035. Due to the possibility of different injection strategies as well as the variation of in-cylinder back pressure, the comprehensive knowledge of hydrogen injection jet behavior and characteristics is fundamental for improving the combustion process in direct injection H2-ICE. In

Montanaro, Alessandro, Mancaruso, Ezio, Meccariello, Giovanni, Allocca, Luigi

Gasoline Particulate Filter Modeling with Catalytic Washcoat and Ash Accumulation and Transient Soot Distribution Prediction

2025-01-8483

04/01/2025

The upcoming EURO 7 and EPA Tier 4 regulations and the possible China 7 are expected to tighten the tailpipe particulate emissions limits significantly. High performance Gasoline Particulate Filters (GPFs) with high filtration efficiency and low pressure drop would be mandated for gasoline engines to meet these stringent regulations. Due to packaging constraints, GPFs are often coated with three-way catalyst (TWC) materials to achieve four-way functionality. Ash accumulation in GPFs also has a significant impact on the performance of GPFs. This paper utilizes 3D CFD to predict the transient filtration efficiency and pressure drop of a washcoated GPF with ash accumulation during the soot loading process. Simulation results show a decent match with experimental data. The 3D CFD model also provides detailed information on soot penetration in the GPF wall substrate and soot cake characteristics on the wall. These information can be crucial for GPF wall substrate design and washcoating

Yang, Pengze, Cheng, Zhen

A Study on Cetane on Demand Technology Part 1 - Development of Fuel Reformer to Improve Fuel Ignitability

2025-01-8447

04/01/2025

The integration of low-octane gasoline with a compression ignition combustion system has been proposed as a strategy to reduce Well-to-Wheel CO2 emissions from automobiles using petroleum-based fuel. In the current situation where low-octane gasoline is not widely available in the market, onboard reforming of commercial gasoline to increase the cetane number (lower the octane number) allows for compression ignition combustion even with commercial gasoline. This requires “Cetane on Demand” technology, which enables compression ignition combustion with both commercial gasoline and low-octane gasoline. It is known that the ignition property of fuel is enhanced when the fuel is oxidized to generate hydroperoxides. Moreover, the use of N-hydroxyphthalimide (NHPI) as a catalyst promotes hydroperoxide generation at low temperatures. The objective of this study is to develop a device that enhances the ignition properties of gasoline through onboard fuel reforming. Initially, from the seven

Hashimoto, Kohtaro, Yamada, Yoshikazu, Matsuura, Katsuya, Kudo, Tomohide, Chishima, Hiroshi, Al-Taher, Maryam, Kalamaras, Christos, Albashrawi, Reem

A Study on the Influence of Compression Pads on the Safety and Life of a Lithium-ion Cell Module

2025-01-8132

04/01/2025

The demand for eco-friendly electric powertrains has increased significantly in recent years. Cells are the most crucial component of a battery pack, directly influencing the dimensions, range, lifespan, performance, and cost of electric vehicles. Lithium-ion cells outperform other cell chemistries due to their higher energy density, allowing for more compact and lightweight designs while providing longer operational ranges. It is crucial that lithium-ion cell packaging complies with assembly requirements to maximize its lifespan and ensure operational safety. Assembly force requirements of lithium-ion cells are critical to ensure optimal cell performance throughout its lifetime & enhance the longevity of the battery pack. The compression pad between cells ensures appropriate cell assembly pressure. The service life is how long a lithium-ion cell can operate effectively, while the cyclic life refers to the number of charge-discharge cycles before cell functional degradation. The cell

Varambally, Vishakha, Sithick basha, Abubakker, Chalumuru, Madhu, Sasikumar, K

The Numerical Study of Methane Flame Characteristics in the Ammonia/Air Environment at Sub-Atmospheric Pressure

2025-01-8450

04/01/2025

The low emission of carbon and minimum level of soot formation in combustion engines and turbines strategy is adopted by many countries to counteract global warming and climate change. The use of ammonia with hydrocarbon fuels can limit the formation of soot and carbon emissions due to non-carbon atoms. The current study explores the use of ammonia with air at coflow flame conditions, which was not tested before. It may give the choice for diesel cycle engines to use the ammonia either with air or fuel. The combustion and emission characteristics of methane coflow flame were studied at low pressure and air polluted by ammonia conditions. The results showed that a significant decline in carbon formation was observed when ammonia was boosted, 5-10%. The impact of sub-atmospheric pressure, 90-70 KPa, on COx development was higher than that of NH3 addition, 0-5%, thanks to the lower formation of hydroxymethylium, formaldehyde, and aldehyde radical. In the environment of lower pressure, the

Hina, Anam, Akram, M Zuhaib, Shafa, Amna, Akram, M Waqar

Impacts of Injection Pressure on Split-Injection Energy-Assisted Compression-Ignition Combustion of Low Cetane Number SAFs with a Gaussian-Shaped Ribbed Piston Bowl Design

2025-01-8350

04/01/2025

The impact of injection pressure on a split-injection energy-assisted compression-ignition (EACI) combustion strategy was studied in an optically accessible engine with a custom ribbed piston bowl design. Three injection pressures (600, 800, and 1000 bar) were investigated for three split-injection dwells (1.5, 2.0, and 2.5 ms) with a fixed second injection timing of -5.0 CAD. The Gaussian-shaped ribbed piston bowl design was employed to position hot combustion gases from the first injection near the centrally located injector to enable rapid ignition and mixing-controlled combustion of the second injection. At 600-bar injection pressure, as injection dwell was shortened, relocation of hot combustion gases near the injector became increasingly more difficult due to less available time for relocation and due to the higher in-cylinder densities at the start-of-injection (SOI) for the first injection. Increased injection pressure (800 and 1000 bar) improved the relocation of the first

Amezcua, Eri, Stafford, Jacob, Kim, Kenneth, Kweon, Chol-Bum, Rothamer, David

Experimental Study of DOC-on-Filter Using Next Generation Filter Solutions for Non-Road Applications

2025-01-8479

04/01/2025

Upcoming California Tier 5 non-road limits mandate 90% and 75% reductions in NOx and PM respectively, from current Tier 4F emission standards. Similarly, lower NOx and PN/PM limits can be expected from a next round of European Non-Road regulations. To meet these limits, more SCR volume for greater NOx reduction, and better filtration efficiency filters for greater PN/PM reduction, may be required. The challenge is to accommodate larger SCR volume while maintaining oxidation (DOC) and filtration (DPF) functionality of the aftertreatment system within a limited packaging space on non-road machineries. Consolidating DOC and DPF into a single component as DOC-on-filter instead of separate DOC and DPF substrates to achieve space saving has been previously discussed in literature. This study expands on the current understanding and explores various functional performance characteristics of the DOC-on-filter concept in comparison with DOC + bare DPF, DOC + PGM coated DPF. The three test

Dam, Mrinmoy, Warkins, Jason, He, Suhao

Consistent Drag Prediction with CFD for a Vehicle with Bimodal Wake Cycling

2025-01-8766

04/01/2025

The vehicle wake region is of high importance when analyzing the aerodynamic performance of a vehicle. It is characterized by turbulent separated flow and large low-pressure regions that contribute significantly to drag. In some cases, the wake region can oscillate between different modes which can pose an engineering challenge during vehicle development. Vehicles that exhibit bimodal wake behavior need to have their drag values recorded over a sufficient time period to take into account the low frequency shift in drag signal, therefore, simulating such vehicle configurations in CFD could consume substantial CPU hours resulting in an expensive and inefficient vehicle design iterations process. As an alternative approach to running simulations for long periods of time, the impact of adding artificial turbulence to the inlet on wake behavior and its potential impact on reduced runtime for design process is investigated in this study. By adding turbulence to the upstream flow, the wake

DeMeo, Michael, Parenti, Guido, Martinez Navarro, Alejandro, Shock, Richard, Fougere, Nicolas, Razi, Pooyan, Oliveira, Danilo, Lindsey, Craig, Yu, Chenxing, Breglia Sales, Flavio

DME-to-Propane Mixture Effects on a Light Duty Compression Ignition Engine

2025-01-8415

04/01/2025

Fuels that can be produced in a sustainable manner are of high interest because they can provide an essential step toward net zero emissions vehicles. This study examines the combustion of two such fuels, Dimethyl Ether (DME) and propane, in a compression ignition, 4-cylinder, 2.2L engine running with mixtures of DME-to-Propane ranging of 100%-0%, 85%-15%, 75%-25%, and 65%-35% by weight. Testing was conducted at 2000rpm - 100Nm, an important representative point in the FTP certification cycle. For each fuel mixture, conditions tested include sweeps of boost, EGR and injection pressure. Tests are mainly conducted at a constant combustion timing with CA10 of -1 deg with respect to TDC, with an engine controller combustion feedback system based on in-cylinder sampling of pressure. Trends of NOx, HC, and CO are similar for the range of DME-to-propane, from 100%-0% to 75%-25%. Boost and injection pressures had the most notable impact on the heat release traces. Higher boost, from

De Ojeda, William, Wu, Simon (Haibao), Hall, Carrie, Ankobea-Ansah, King, Hassan, Hafiz Ahmad, Harrison, Christopher

Effect of Catalyst Coating Strategy on NOx Reduction and Passive Soot Oxidation for Selective Catalytic Oxidation-Selective Catalytic Reduction Catalyst on Diesel Particulate Filter

2025-01-8490

04/01/2025

Selective catalytic oxidation/reduction catalysts coated on diesel particulate filters (SDPF) are an important technology route to meet next-stage emission regulations. The previous research of the research group showed that compared with SDPF coated with Cu-SSZ-13, the SDPF coated with novel selective catalytic oxidation-selective catalytic reduction (SCO-SCR) catalyst, which combined MnO2-CeO2/Al2O3 and Cu-SSZ-13, can simultaneously improve NOx reduction and soot oxidation performance. Catalyst coating strategy is an important parameter affecting the performance of SDPF. In this study, the effects of different coating strategies of SCO-SCR catalysts (C25, C50, C75, and C100) on the performance of NOx reduction and soot oxidation in SDPF were investigated. The results show that, as the inlet gas temperature increases, NO emissions first decrease and then increase, NOx conversion efficiency first increases and then decreases, and the rich-NO2 area, NH3 oxidation rate, N2O, CO, CO2

Chen, Ying-jie, Tan, Piqiang, Yao, Chaojie, Lou, Diming, Hu, Zhiyuan, Yang, Wenming

Minimum Standard for Portable Gaseous, Oxygen Equipment

AS1046C (Current)

03/27/2025

This standard is intended to apply to portable compressed gaseous oxygen equipment. When properly configured, this equipment is used either for the administration of supplemental oxygen, first aid oxygen or smoke protection to one or more occupants of either private or commercial transport aircraft. This standard is applicable to the following types of portable oxygen equipment: a Continuous flow 1 Pre-set 2 Adjustable 3 Automatic b Demand flow 1 Straight-demand 2 Diluter-demand 3 Pressure-demand c Combination continuous flow and demand flow.

A-10 Aircraft Oxygen Equipment Committee

Optimization of Abrasive Water Jet Machining of Al 6061-T6 Alloy Using Taguchi-Based Gray Relational Analysis-Coupled Principal Component Analysis Hybrid Approach

05-18-03-0023

03/13/2025

Abrasive water jet (AWJ) machining is the most effective technology for processing various engineering materials particularly difficult-to-cut materials such as aluminum alloys, steels, brass, ceramics, composites, and the like. The present study focuses on the experimental study on surface roughness and kerf taper is carried out during AWJ machining of Al 6061-T6 alloy with 40 mm thickness, and the influence of process parameters includes water jet pressure, standoff distance, and abrasive flow rate on the kerf taper and surface roughness is analyzed. The number of experiments is designed using Taguchi’s L9 orthogonal array. Experimental results are statistically analyzed using ANOVA. Also gray relational analysis (GRA) coupled with principal component analysis (PCA) hybrid approach was implemented to optimize the performance parameters. From the results it is found that standoff distance and hydraulic jet pressure are the most influencing parameters on surface roughness and kerf

Kolluri, Siva Prasad, Srikanth, V., Ismail, Sk., Bhanu, C.H.

CFD-Based Comfort Parameter Evaluation of a Flow Vectoring Air Vent System for Car Cabins Using a Reduced Order Model

15-18-02-0012

03/03/2025

This computational fluid dynamics (CFD) study examines the comfort parameters of an innovative air vent concept for car cabin interiors using a reduced order model (ROM) and proper orthogonal decomposition (POD). The focus is on the analysis of the influence of geometric and fluid mechanical parameters on the resulting jet, in particular on the deflection angle of the airflow and the total pressure difference along the outlet geometry. Different parameters of the investigated system, such as the surface orientation, the outlet height, the separator distance, and the separator height, lead to different effects on the airflow structure. The results show that changes in the air vent surface orientation are always accompanied by an increase in the deflection angle and the total pressure difference. In contrast, the variation of the outlet height ratio positively influences the deflection angle and the total pressure difference in terms of the requirements for air vent geometries. The study

Langhorst, Sebastian, Mrosek, Markus, Boughanmi, Nesrine, Schmeling, Daniel, Wagner, Claus

A Comparative Study on the Working Efficiency of Journal Bearing Employing Different Micro-Textures

04-18-02-0011

02/19/2025

This study proposed the different micro-textures of the SC (square cylinder), SWS (square wedge shape), HS (hemispherical shape), and CR (cylindrical round) to improve the working efficiency of the journal bearing. A hydrodynamic lubrication model of the journal bearing under the impact of the changing dynamic loads is established to analyze the performance of micro-textures. The maximum oil film pressure and minimum frictional force in the journal bearing are selected as two evaluation indices. Some outstanding research results show that all the SC, SWS, HS, and CR added on the bearing surface improved the working efficiency of the journal bearing better than without the micro-textures. Moreover, the HS also improved the working efficiency of the journal bearing better than other structures of SC, SWS, and CR. To optimize the working efficiency of the journal bearing using HS, the dimension ltex and depth htex of HS should be selected and designed in a range of 3.6 < ltex ≤ 3.9 mm and

Song, Fengxiang, Nguyen, Vanliem, Liu, Yaxi

Quantifying Hydroplaning Risk: Insights from Water Film Thickness Measurements on Maryland Highways

02-18-02-0010

02/19/2025

Wet pavement conditions during rainfall present significant challenges to traffic safety by reducing tire–road friction and increasing the risk of hydroplaning. During high-intensity rain events, the roadway pavement tends to accumulate water, forming a film that can have serious implications for vehicle control. As the longitudinal speed of the vehicle increases, a water wedge forms in front of the tire, leading to partial loss of contact with the road. At critical hydroplaning speed, a complete water layer forms between the tire and the road. Although less common, dynamic hydroplaning poses severe risks when high-intensity rainfall coincides with high vehicle traveling speed, leading to a complete loss of control over vehicle steering capabilities. This study advances hydroplaning research by integrating real-world data from the Road Weather Information System (RWIS) with an existing hydroplaning model. This approach provides more accurate hydroplaning risk assessments, emphasizing

Vilsan, Alexandru, Sandu, Corina, Anghelache, Gabriel

A Novel Approach to develop the Exhaust Backpressure Measurement System for Automotive Application

2025-28-0168

02/07/2025

Backpressure is one of key acoustic performance evaluation criteria of exhaust muffler (or Silencer) /EATS (Exhaust after treatment system) as well as for the exhaust system. Exhaust back pressure is an important parameter for fuel efficiency of a vehicle. Typically, the engine manufacturer specifies an upper limit for this. Usually, exhaust back pressure is measured during the driving condition of the vehicle at maximum power condition of the engine either on road or on chassis dynamometer. Both these methods, need a lot of preparatory works, test setup arrangement, 3 or more manpower and special skills. In this research, authors are tried to develop a new backpressure measurement set up for automotive vehicle application, which is simple and innovative, to fulfill the backpressure test requirement. In this design, mainly following devices are used namely Pitot tube, Compressed air, Manometer (or pressure gauge), Thermocouple, Fluke thermometer, along with standalone exhaust layout

Mandal, Goutam, Biswas, Sanjoy

Enhancing Flow and Heat Transfer Characteristics in Microchannels with Various Nanofluids

2025-28-0024

02/07/2025

The substantial growth of power converters in electric vehicles necessitates more energy consumption and, as a result, greater heat generation. To avoid the power converter’s excessive heat, an innovative curved microchannel with diamond-shaped and pentagonal cross-sections was developed. The flow and heat transfer characteristics of the Gc3N4/Water (0.3%), Al2O3/Water (0.3%), and Al2O3-Gc3N4/Water (0.3%) hybrid nanofluid were assessed. The experimental investigation was carried out by different mass flow rates of about 0.1 to 0.5 LPM under a uniform heat flux of 50 kW/m2. The heat sink had a cross-sectional area of 80×48mm2. In comparison to the diamond channel heat sink through hybrid nanofluids, findings from experiments resulted that the heat transfer rate and pressure drop for the diamond channel enhanced by 14.2% and 18.9%, respectively. In comparison to Gc3N4/Water and Al2O3/Water nanofluids, the hybrid nanofluid improved the heat transfer rate for the diamond micro channel heat

R L, Krupakaran, Petla, Ratna Kamala, Anchupogu, Praveen, Kala, Lakshmi K, Gangula, Vidyasagar Reddy, Tarigonda, Hariprasad

CFD Analysis on the Effect of Circular Cavity at Different Location of Airfoil Surface

2025-28-0074

02/07/2025

The paper present numerical effects of supercritical airfoil SC (2) 0414 having circular cavities at three different chord wise locations from leading to trailing edge. Here passive control method is widely applied by altering the \baseline airfoil surface coordinates to ascertain the aerodynamic behavior of the cavity at 40 %, 50 % and 60 % of the chord length respectively. The cavity shapes were deformed using Bezier curve to observe vortex pattern in the cavity region. Structured meshing was employed. The analysis was performed on SC 2 (0) 414 two-dimensional airfoil using commercial CFD ANSYS Fluent software where Spalart- Allmaras turbulence model technique is chosen to solve boundary layer problems on adverse pressure gradient and tested at extended range of angle of attack (-150 to 150) at Mach number 0.85. The study highlights the aerodynamic characteristics of lifting coefficient, drag coefficient and lift to drag ratio. It was observed that the cavity in suction surface

Pushparaj, Catherine Victoria, P, Booma Devi, D, Piriadarshani, Ganesan, Balaji, Ganesan, Santhosh Kumar, Raja, Vijayanandh

Research of Pressure Control Based on Dither

2025-01-7040

01/31/2025

The purpose of the paper is to study the impact of dither on how to improve the pressure control capability in common rail system. The dither is directly operating to the inlet metering valve and making the metering flow accuracy. The correlation between rail pressure and metering flow was analyzed. Optimizing the inlet metering valve control is to improve the pressure control. To overcome the hysteresis problem of the inlet metering valve and improve its stability and rapidity on the pressure control. The PID control strategy based on the pressure control were applied in the common rail system and many papers have introduced the logical. But the dither application was seldom introduced in the common rail system. The dither was specified for the inlet metering valve. With the proper dither signal, the stick-slip motion of the metering valve spool converted to a steady one and the dynamic performance was optimized. To verify the theoretical and calibrated the proper dither signal, the

Kuang, Pengda, Chen, Huiqing, Zhang, Jing, Ran, Ye

A Comparative Study of Combustion and Performance in Diesel Engines Fueled by Mosambi Peel Biodiesel-Butylated Hydroxytoluene Nanoparticles Blend

2024-01-5258

01/28/2025

This study’s objective is to examine the combustion and performance of mosambi waste peel biodiesel (MWPB) combined with butylated hydroxytoluene (BHT) nanoparticles as a substitute fuel for diesel engines. It also aims to assess the impact of this blend on engine combustion, such as in-cylinder pressure, heat release rate (HRR), ignition delay (ID), combustion duration (CD) and mass fraction burnt (MFB) and performance indicators, including brake thermal efficiency (BTE), brake-specific energy consumption (BSEC), engine torque, exhaust gas temperature (EGT), indicated mean effective pressure (IMEP), air-fuel ratio (A/F ratio) and volumetric efficiency, while also considering the feasibility of employing waste materials in fuel generation. The experimental configuration utilized a research diesel engine functioning under standard conditions, emphasizing the maintenance of uniform injection pressure to ensure optimal fuel atomization and combustion. The test fuels are diesel, MWPB, MWPB

Jayabal, Ravikumar, Madhu, S., Devarajan, Yuvarajan, Domian, Christopher Selvam

Effect of Gasification Temperature on Biohydrogen Derived from Waste Agro Products for Alternative Fuel Application

2024-01-5260

01/28/2025

Hydrogen fuel is becoming a popular choice in many energy applications because of its innovative green technology, which produces zero carbon emissions. It also offers better efficiency than fossil fuels. Current research focuses on obtaining hydrogen energy from agricultural waste using a gasification process. This process involves heating the waste at gasification temperatures 300, 400, 500, 600, and 700°C, maintaining a residence time of 60 minutes, and applying a gasification pressure of 20 bar. The effects of gasification temperature on the effectiveness of hydrogen production are examined. At a high gasification temperature of 700°C and a residence time of 60 minutes, the processed agro feedstock showed impressive results. It achieved a molar fraction of 12% carbon dioxide (CO2), 31% methane (CH4), and 55% hydrogen (H2), leading to an improved hydrogen yield of 15.2 mol/kg. Additionally, it demonstrated better hydrogen selectivity at 8.1 and a higher gasification efficiency of 61

Venkatesh, R., De Poures, Melvin Victor, Raguraman, B., Marimuthu, S., Devanathan, C., Baranitharan, Balakrishnan, Madhu, S., Kaliyaperumal, Gopal, Manickaraj, Pethuraj

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

10-09-01-0008

01/24/2025

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

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

Aerospace - Evaluation of Particulate Contamination in Hydraulic Fluid - Membrane Procedure

ARP4285A (Current)

01/09/2025

This SAE Aerospace Recommended Practice (ARP) establishes a method for evaluating the particulate matter extracted from the working fluid of a hydraulic system or component using a membrane. The amount of particulate matter deposited on the membrane due to filtering a given quantity of fluid is visually compared against a standard membrane in order to provide an indication of the cleanliness level of the fluid.

A-6C1 Fluids and Contamination Control Committee

The Use of Pressure Constructs in Aerodynamics May Lead to Misinformation

01-17-03-0020

01/06/2025

From biology, to genetics, and paleontology, these fields share the DNA as a common and time-proven tool. In science, pressure may be such a tool, shared by thermodynamics, material science, and astrophysics, but not by aerodynamics. Pressure is a shorthand for a force acting perpendicular to a surface. When this surface is reduced to zero, so should the pressure. The wing area of an aircraft acts as a reference area to calculate its parasite drag coefficient. In this scenario, the parasite drag acts as a force over the wing area. If the wing area is reduced to zero, its parasite drag does not, as the fuselage is still generating parasite drag. The ratio of the parasite drag and wing area is an example of a pressure construct that uses a physically irrelevant reference area and has no absolute zero. Pressure constructs, more frequently used than pressures in aerodynamics, are a math-based parameter that preserve dimensional propriety according to the Buckingham Pi theorem but lacks a

Burgers, Phillip

Enhancing Engine Lubrication: Design and Evaluation of Oil Sump Surge Control in Racing Vehicles

2024-36-0074

12/20/2024

During accelerations and decelerations of a race car whose engine has a wet sump, the forces generated by the vehicle’s motion cause the engine oil to vigorously shift towards the walls of the oil pan and crankcase, contributing to the phenomenon known as ‘sloshing.’ This phenomenon often leads to fluctuations in oil pressure, resulting in oil pressure surge, when the oil is pushed away from the pump pickup point. Via the logged data, the Formula UFSM FSAE Team had witnessed a recurrent lack of oil pressure in the race track during the 2023 Brazilian FSAE competition. In the AutoCross Event, the recurrence of this problem was 80% of the right corners on lateral accelerations between 0.80G and 1.30G. The average oil pressure in this condition was 0.80 bar, even reaching 0.10 bar above 5000 RPM. Therefore, it was necessary to develop a new set of baffles for the oil pan, capable of minimizing the effects of sloshing and, consequently, the oil surge. As a method of research, a test bench

Zimmermann, Natalia Diovana, Junior, Luiz Alfredo Coelho, Martins, Mario, Hausen, Roberto

Response Surface Methodology-Based Multi-Objective Optimization for Biofuel-Powered Engine Response Map Development under the Steady-State Operating Conditions

03-17-08-0063

12/20/2024

The twin challenges of the automotive industry namely petroleum dependence and environmental pollution paved way for the development of an environmentally friendly and feasible substitute for diesel, possessing power characteristics equivalent to those of a diesel engine. Biofuel has potential as a renewable energy source, offering a more sustainable alternative to traditional fossil fuels. However, it does come with some challenges, such as varying quality and combustion properties. To enhance its performance, engines can be fine-tuned by adjusting fuel injection parameters, such as timing, pressure, and duration. Accordingly, this research article focuses on optimizing the fuel injection parameters for a CRDi engine powered by D+LPO (20% lemon peel oil and 80% diesel) biofuel, with the goal of improving both performance and emission characteristics. The experimental design matrix was generated using Design Expert-13 software, employing the I-optimal technique. Utilizing response

Saiteja, Pajarla, Ashok, B.

2024 Create the Future Design Contest: Medical Category Winner - A Smart Contact Lens for Glaucoma Management

TBMG-52152

12/01/2024

Hamdi Torun Arda Deniz Yalcinkaya Gunhan Dundar Ozgue Kaya Northumbria University, Newcastle Upon Tyne, UK

Smart Contact Lens for Glaucoma Detection

TBMG-52160

12/01/2024

Researchers have been testing ways to continuously and more comfortably detect these tiny fluctuations in pressure. A prototype smart contact lens measures eye pressure accurately, regardless of temperature. The contact lens wirelessly transmits real-time signals about eye pressure across a wide range of temperatures.

Failure of Power Steering Gears of the Heavy-Duty Trucking: A Tribological Investigation

2024-01-4300

11/05/2024

A power steering system helps the heavy-duty operator move the vehicle easily with the hydraulic pump that provides the fluid pressure and facilitating adequate operation. Some failures in the power steering system are due to external and internal factors that can reduce its service life. The external factors could be identified by ocular inspection but normally, due to internal failures, it is necessary to use a hydraulic pressure flow meter. However, this device makes it impossible to detect failures caused by the selected lubricant. This work aims to investigate the causes of power steering system seizure by using the tribological wear examination process and the lubricant characterization under some actual operation conditions. The lubricant characterization was carried out in a four balls tester using fresh and used samples of a re-refined oil based ATF, SAE 15 W40 and synthetic SAE 5 W30 oils at two temperatures. In general, the results showed an unsteady friction profile with

García-Maldonado, Miguel, Gallardo, Ezequiel, Mozqueda-Flores, Luis, Vite-torres, Manuel

Parametric Study of Methanol Combustion Assisted by Glow Plug in a Low-Duty Diesel Engine

2024-01-4284

11/05/2024

This work numerically investigated the feasibility of methanol compression ignition combustion for light-duty diesel engine applications by using a glow plug (GP) to promote ignition. A comprehensive parametric study was conducted to assess the combustion characteristics depending on the GP position, the relative angle between the GP and injector, and other initial conditions. Optimal design parameters were identified. It was demonstrated that GP can enable successful ignition and combustion of methanol at the operating conditions under study. Among the many parameters considered, the relative angle between the GP and injector was found to be one of the most critical parameters in controlling the ignition and complete combustion. Increasing intake temperature promoted combustion speed and engine performance, but excessively high intake temperatures led to higher wall heat transfer loss and lower ITE. An appropriate level of the pilot injection mass was found to increase ITE, with the

Liu, Xinlei, Sim, Jaeheon, Raman, Vallinayagam, Viollet, Yoann, AlRamadan, Abdullah S., Cenker, Emre, Im, Hong G.

High-Load Operating Characteristics of Planar Membrane Humidifiers of Polymer Electrolyte Membrane Fuel Cell Systems for Heavy-Duty Applications

2024-01-4323

11/05/2024

To gain high efficiencies and long lifetimes, polymer electrolyte membrane fuel cell systems require precise control of the relative humidity of the cathode supply air. This is usually achieved by the use of membrane humidifiers. These are passive components that transfer the product water of the cathode exhaust air to humidify the supply air. Due to the passive design, controllability is achieved via a bypass. It is possible to use map-based control strategies to avoid the use of humidity sensors. Such map-based control requires deep insights into the humidifier behavior in all possible thermodynamic operating states, including various water loads. This paper focuses on typical operating conditions of heavy-duty application at high load, specifically on the occurrence of liquid water in the cathode exhaust gas, which has not been sufficiently investigated in the literature yet. In order to simulate these conditions, we built a test rig with an optically accessible single-channel set

Mull, Sophie, Weiss, Lukas, Wensing, Michael

Tire Pressure and Temperature Monitoring Systems for Trailers under 26000 Pounds GVWR

J3309_202410 (Current)

10/28/2024

This SAE Recommended Practice defines the system and component functions, measurement metrics, and testing methodologies for evaluating the functionality and performance of tire pressure systems for use on trailers under 26000 pounds GVWR within the known operating environments. This document is applicable to all towed trailers under 26000 pounds GVWR. Examples of towed trailers are recreational vehicle travel trailers and fifth wheels, utility trailers, cargo trailers, livestock trailers, flatbed trailers, boat trailers, and snowmobile trailers. These trailers can be equipped with one, two, or three axles with each axle supporting either two or four tires. These systems are recommended to address all tires in service as originally installed on a trailer by the OEM. This recommended practice can also be applied to external TPMS that also cover tow vehicles and trailers simultaneously. This document will focus on tire pressure systems of the monitoring type.

Trailer Committee

Numerical Investigation on Performance Based Methodology for Developing Vane Design of AC Duct

2024-28-0004

10/17/2024

Airflow directionality in a vehicle cabin is one of the concerns of car owners, researchers, and vehicle manufacturers. After exposed/parked in hot ambient condition for a long time, HVAC system normally takes few minutes to cool down and reach an acceptable cabin temperature for the passenger comfort. To ensure proper airflow distribution inside the cabin, the AC duct & vanes ability to direct airflow must be evaluated. Objective of this work is to propose a methodology for developing the vane design of AC system duct using CFD approach. Two different goals are attempted. Firstly, the effect of horizontal and vertical vane angle on airflow directionality is investigated with DoE approach. Then factors influencing the airflow directionality are investigated using factorial study approach. CFD based factorial analysis (L9 orthogonal array) was conducted using three components at three levels. The impact of number of horizontal vanes, number of vertical vanes and distance between them on

Mahesh, A, Baskar, Subramaniyan, Raju, Kumar, Gopinathan, Nagarajan

FITTING END, STRAIGHT THREAD, HIGH PRESSURE, BOSS CONNECTION, DESIGN STANDARD

AS1941B (Current)

10/08/2024

G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies

Aircraft Turbine Engine Pneumatic Component Contaminated Air Endurance Test

ARP4014A (Current)

10/03/2024

This SAE Aerospace Recommended Practice (ARP) describes a method of conducting an endurance test using contaminated air when the applicable specification requires non-recirculation of the contaminants. The objective of the test is to determine the resistance of the engine mounted components to wear or damage caused by the contaminated air. The method described herein calls for non-recirculation of the contaminants and is intended to provide a uniform distribution of the contaminant at the inlet to the Unit Under Test (UUT). The UUT may require the use of a hydraulic fluid for actuation of components within the test unit. Contamination of the test hydraulic fluid is not part of this recommended practice. If contaminated hydraulic fluid is required by the applicable test specification, refer to MAP749.

AC-9 Aircraft Environmental Systems Committee

Air Quality for Commercial Aircraft Cabins

AIR4766 (Current)

10/03/2024

This SAE Aerospace Information Report (AIR) provides information on air quality and some of the factors affecting the perception of cabin air quality in commercial aircraft cabin air. Also a typical safety analysis process utilizing a Functional Hazard Assessment approach is discussed.

AC-9 Aircraft Environmental Systems Committee

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