Browse Topic: Powertrains

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Tailoring ICEs towards future global market requirements – Multi-Fuel Capability to ensure next decade market success2026-24-0030To be published on 09/21/2026
The entire mobility industry is actually according to the Paris agreement and the corresponding initiatives facing enormous regulatory demands to eliminate the business sector-related GHG emissions. A major focus is hereby set on wide-spread electrification of all kinds of applications, but from current perspective it is obvious that a quick and complete shift is highly unlikely, especially with view a heavy and challenging industrial and commercial applications. In line with this, it’s apparent, that ICEs maintain to play an important role in the overall propulsion system line-up. For compliance with the engaged CO2 reduction policies and efficiency improvement demands, a fast and broad replacement of fossil fuels needs to be realized. Due to the specific properties of carbon-neutral fuels and as well the variety of the range of industrial applications, different types of alternative fuels are considered, subdivided in preferred solutions for smaller or on-highway applications vs
Koerfer, Thomas
Structural Robustness and Regime-Dependent Uncertainty in a Reduced-Order Physics Model for Vehicle Fuel Consumption Using Monte Carlo Analysis2026-24-0015To be published on 09/21/2026
Accurate prediction of vehicle fuel consumption typically relies either on simplified empirical correlations or on high-fidelity simulations that are computationally expensive. However, the structural robustness of reduced-order physics-based models under parametric uncertainty has not been systematically quantified. In particular, the interaction between model simplifications and uncertainty in vehicle and fuel properties across different operating regimes remains insufficiently investigated. This study presents a reduced-order physics-based framework derived from fundamental force and energy balances to estimate fuel consumption in L/100 km. The model includes aerodynamic drag, rolling resistance, inertial effects, drivetrain efficiency, and fuel lower heating value. Unlike purely empirical formulations, the proposed structure preserves physical interpretability while remaining computationally efficient. Monte Carlo simulations are employed to propagate simultaneous uncertainties in
Gutierrez, Marcos, Taco, Diana
Adaptive Neural Network Fuel Mass Correction for Structural Model Error Compensation in Diesel Engines with Variable Biodiesel Properties2026-24-0023To be published on 09/21/2026
Compression-ignition engines operating with biodiesel blends often exhibit variability in fuel properties, such as density, viscosity, and cetane number, which can lead to systematic deviations in injected fuel mass when using conventional physics-based models. These deviations can reduce combustion efficiency and increase brake-specific fuel consumption (BSFC). This study proposes a lightweight neural network–based approach to compensate for structural errors in baseline injection models, using a single-layer perceptron trained on the relative error (delta) between actual and modeled injected mass. By normalizing engine and fuel parameters and introducing a small amount of measurement noise, the network learns to predict a corrective factor that adapts the injected mass to match the desired target under varying fuel conditions. Simulation results demonstrate that the neural correction significantly reduces systematic bias: in test cases with intentionally introduced structural error
Gutierrez, Marcos, Taco, Diana, Sampietro-Saquicela, Jose, Bermudez-Herrera, Leandro
Thermal Effects and Combustion Behaviour of Hydrogen and Natural Gas in a Heavy-Duty Gas Engine2026-24-0003To be published on 09/21/2026
To accelerate the usage of renewable fuels in the heavy-duty transportation sector, a conventional diesel heavy-duty engine was retrofitted for gaseous fuel operation. The aim of this approach was to support the transition from diesel to renewable energy carriers while maximizing the reuse of existing engines in the field. A direct conversion from liquid to gaseous fuel usage does not guarantee stable or efficient engine operation. Gaseous fuels require an external ignition source to initiate combustion. Hydrogen exhibits a low minimum ignition energy and a wide flammability range in air. These characteristics lead to high demands on combustion development. In spark-ignited internal combustion engines, port fuel injection (PFI) is widely used due to its simpler system integration and lower fuel pressure level compared to direct injection (DI). PFI is associated with several inherent disadvantages, including lower volumetric efficiency and an increased sensitivity to abnormal combustion
Rößlhuemer, Raphael, Fitz, Patrick, Fellner, Felix, Prager, Maximilian, Jaensch, Malte
Electrical waveform analysis of spark discharge for monitoring conditions inside prototype prechambers2026-24-0013To be published on 09/21/2026
Using renewable fuels like hydrogen in internal combustion engines requires new combustion strategies and ignition systems like pre-chamber sparkplugs. This necessitates novel measurement and monitoring techniques to gain insights into the phenomena arising from the use of new fuels and components. For understanding the phenomenon of pre-chamber ignition, it is important to observe how sparks behave inside them. The spark-elongation under certain conditions inside a particular pre-chamber, its location at a given time during discharge, and the flow conditions during spark discharge are all significant factors in gaining insight into this phenomenon. However, such information is difficult to obtain from inside a pre-chamber due to the difficulty of gaining optical access. In such cases, the electrical waveform analysis could prove useful. During this study, the electrical parameters are used to calculate the spark length, providing information about the igniting volume inside a pre
Kottakalam, Saraschandran, Nenzel, Markus, Rottenkolber, Gregor
Business approach to cope with automotive market uncertainty2026-24-0024To be published on 09/21/2026
The global automotive industry is facing an unprecedented convergence of uncertainties driven by geopolitical tensions, evolving trade policies, emissions related regulations, and increasingly volatile consumer demand. Shifting emissions legislation, including the EU’s tightened CO2 targets and long term plans to phase out internal combustion engines, is imposing strategic and financial pressures on automakers and suppliers as they navigate divergent regional regulatory trajectories. Demand side volatility further complicates the landscape. Consumer preferences are fluctuating due to economic pressures, infrastructure constraints, and uneven EV adoption patterns. While some markets show stagnation in battery electric vehicle uptake, hybrids are rising as consumers seek cost efficient alternatives amid uncertain energy and regulatory environments. Within this unstable context, the transition toward Software Defined Vehicles (SDVs) is emerging as a critical strategic response. SDVs
Cavanna, Filippo, Potenza, Luca
A computational study of high efficiency Wankel rotary engines using a passive pre-chamber2026-24-0001To be published on 09/21/2026
Wankel rotary engines are renowned as compact machines with high power-to-weight ratios, which make them suitable for use as range extenders for battery electric vehicles or as propulsion systems for unmanned aerial vehicles. However, their overall efficiency and emissions still need significant improvement to make them compliant to make them stringent regulations and comparable with classical reciprocating 4-stroke engines. With the aim of improving these shortcomings, this work focuses on the application of a passive pre-chamber in order to enhance the combustion phase and the overall efficiency and emissions of such engines. The study was conducted using CFD methods by implementing numerical models of the commercial AIE 225CS rotary engine in CONVERGE, configured with port fuel injection and fully-premixed gasoline combustion. The engine was extensively tested in a previous project while different CFD models were validated against experimental data in previous studies by the same
Vorraro, Giovanni, Im, Hong G., Turner, James
System Dynamics Modeling of Global Electric Vehicle Adoption Using Vensim: Market Transition Time Toward a Single-Dominant Transport Technology2026-24-0017To be published on 09/21/2026
This study presents a system dynamics framework to estimate the transition time required for electric vehicles (EVs) to become the dominant and potentially unique global transportation technology. The model is developed in Vensim and structurally inspired by the classical system dynamics archetypes Growth of a Field, Capacity and Market Growth, and Competitive Dynamics. These reference structures are integrated into a unified dynamic model that captures technological diffusion, production capacity expansion, infrastructure deployment, cost reduction through learning effects, and competition with internal combustion engine (ICE) vehicles. The proposed model represents EV and ICE fleets as interacting stocks, with feedback loops describing market attractiveness, charging infrastructure growth, battery cost decline, policy incentives, and phase-out pressures on conventional vehicles. Nonlinear reinforcing and balancing feedback mechanisms are used to simulate tipping points and saturation
Gutierrez, Marcos, Taco, Diana, Sampietro-Saquicela, Jose, Ulloa de Souza, Raul
Neural-Network-Enhanced Air-Standard Thermodynamic Modeling for Spark-Ignition Engines Fueled with Low Heating Value Alternatives2026-24-0016To be published on 09/21/2026
This study presents a computational framework that integrates an air-standard thermodynamic engine model with artificial neural networks to predict the performance of spark-ignition (SI) engines operating with alternative fuels of reduced lower heating value (LHV). A deterministic thermodynamic simulator was developed in Excel, incorporating engine geometric parameters (compression ratio, bore, stroke, displacement), operating speed, and fuel properties, with particular emphasis on LHV as the dominant energetic descriptor. The model computes in-cylinder states, thermal efficiency, indicated mean effective pressure, and power output under idealized air-standard assumptions. To extend predictive capability beyond fixed-parameter analyses, a feedforward neural network was trained using datasets generated from systematic parametric sweeps of engine geometry, speed, and fuel LHV. The neural network captures nonlinear interactions between compression ratio, combustion energy release, and
Gutierrez, Marcos, Taco, Diana, Sampietro-Saquicela, Jose, Valencia-Ortiz, Nakira
Multi-Level CFD and System Simulation Approach for Optimization of Cooling Circuits in High Power Density Powertrains2026-24-0009To be published on 09/21/2026
This paper presents a CFD-based optimization workflow for the simulation and development of automotive cooling circuits, integrating three-dimensional steady-state analyses with one-dimensional transient modeling. The objective of the activity is to establish a robust methodology that links detailed component-level thermal characterization to system-level dynamic simulations, enabling the assessment of cooling performance under both driving and charging operating conditions. The thermal behavior of the cooling circuit components was first investigated using three-dimensional steady-state simulations performed with Ansys Fluent. For each relevant operating point, the fluid flow and heat transfer were resolved in full 3D, and temperatures were monitored at multiple locations within the components and along the circuit. The steady-state analyses provided spatially resolved temperature fields and heat transfer characteristics for a range of boundary conditions representative of real
Chiappini, Daniele, Tribioli, Laura, Rodionov, Artem
Optimal Eco-Driving for Electric and Conventional Refuse Trucks: a Comparative Analysis of Actual Speed, Energy Efficiency, and Travel Time.2026-24-0031To be published on 09/21/2026
Achieving significant reductions in energy consumption and CO₂ emissions in the transportation sector is a key challenge for sustainable mobility, particularly for vocational trucks operating under demanding driving and duty cycles. Beyond technological advancements in powertrain design, energy efficiency can be improved through optimized driving strategies. In this context, eco driving has emerged as an effective approach to reduce energy consumption by optimizing the speed profile under given operational constraints. Eco driving optimization strategies are indeed particularly well suited to predefined and repetitive driving cycles, such as those typically encountered in waste collection. This work presents a comparative analysis between electric and internal combustion engine powertrain configurations applied to refuse trucks and vehicles, highlighting the impact of intrinsic differences on optimal speed profiles, energy consumption, and travel time. Both configurations are required
Giacobbo, Andrea, Villani, Manfredi, Beltrami, Daniele, Tribioli, Laura, Iora, Paolo, Uberti, Stefano
Passive Thermal Management Through Vapor Chamber Integration of a PMSM E-Motor installed on UAV for Urban Mobility Applications2026-24-0010To be published on 09/21/2026
Thermal management represents a critical design aspect for Permanent Magnet Synchronous Motors (PMSMs) employed in Unmanned Aerial Vehicle (UAV) propulsion systems, where high power density and compact integration lead to significant heat generation. Excessive temperatures may compromise efficiency, reliability, and lifetime, making effective yet lightweight cooling strategies essential. The integration of a vapor chamber is investigated as a fully passive thermal management solution for a commercially available PMSM intended for UAV applications. Unlike active cooling systems, the proposed approach does not require moving parts, external power supply, or additional control devices. The vapor chamber operates through phase-change heat transfer mechanisms, enabling an enanched heat dissipation, exploiting the whole external surface of the vapor chamber; consequently the system naturally adapts to local thermal loads and provides self-regulating behavior without auxiliary components. A
Benedetti, Silvia, Lombardi, Simone, Federici, Leonardo, Chiappini, Daniele
Simulation-Based Development and Evaluation of Heat-Quantity-Based Thermal Operating Strategies for Automotive Applications2026-24-0012To be published on 09/21/2026
Efficient and robust thermal management is a key prerequisite for reproducible vehicle testing and energy-efficient powertrain operation. Conventional thermal operating strategies are commonly based on temperature setpoints and often neglect the dynamic relationship between heat input, system inertia and transient operating conditions, leading to increased energy demand and limited reproducibility under highly dynamic driving cycles. This paper presents a simulation-based development and evaluation of a heat-quantity-based thermal operating strategy for automotive applications. Instead of controlling the system solely via temperature targets, the proposed approach utilizes accumulated and instantaneous heat input as central decision variables for thermal control, explicitly accounting for thermal system dynamics. The investigation is conducted using a detailed vehicle simulation model including a physically-based thermal system representation. An innovative decentralized thermal
Stenger, Erik, Fiore, Luis, Weimer, Niko, Beidl, Christian
Experimental and Numerical Investigation of Hydrogen Direct Injection in a CI Engine2026-24-0004To be published on 09/21/2026
Compression ignition (CI) engines are widely used in the transportation sector due to their high torque and efficiency. However, the current climatic framework limits their application, favouring the adoption of low- and zero-carbon technologies. In this context, hydrogen represents a viable energy source for driving CI engines towards clean combustion. The benefits of hydrogen enrichment in diesel engines have been extensively investigated, particularly in port fuel injection (PFI) configurations. In contrast, the addition of a hydrogen direct injection system within a Common Rail engine remains largely unexplored. In this work, a piezo-actuated outward-opening direct injector fuelled by hydrogen was investigated through a combined experimental and numerical approach. The experimental campaign was conducted on an optically accessible single-cylinder research engine (SCRE), with the injector mounted in the cylinder head. Different injection strategies were explored in terms of duration
Episcopo, Domenico, Rossetti, Salvatore, Mancaruso, Ezio, Saponaro, Gianmarco, Lorusso, Leonardo, Camporeale, Sergio, Laera, Davide
Thermal Management of Pre-Chamber Spark Plugs for the Mitigation of Abnormal Ignition in Hydrogen-Fueled Engines – An Experimental and Numerical Study2026-24-0007To be published on 09/21/2026
The internal combustion engine will continue to contribute to global mobility, particularly when operated with CO₂-neutral or low-carbon fuels. Pre-chamber ignition systems are increasingly investigated to meet future requirements regarding efficiency, emissions, and combustion stability. In combination with hydrogen as a carbon-free fuel, pre-chamber spark plugs enable a significant extension of the lean operating limit while ensuring reliable ignition under demanding boundary conditions. A key development challenge is the thermal management of the pre-chamber spark plug. While the thermal behaviour of conventional production spark plugs is well established, limited knowledge exists for pre-chamber systems. The interaction of chamber geometry, material selection, manufacturing and joining processes, and installation position in the cylinder head strongly influences thermal loading and operational behaviour. Excessive local temperatures may promote knock, pre-ignition, or material
Nenzel, Markus, Alkezbari, Ahmad Anas, Rottenkolber, Gregor
Emissions reduction assessment in buses during real driving tests using hydrogen-methane blends as fuel2026-24-0006To be published on 09/21/2026
Increasing concern over climate change on planetary scale and urban pollution on a local spatial dimension are the pressing needs which invite to reduce greenhouse gas emissions in transportation as well as pollutant emissions. Both goals have prompted governments, industry stakeholders, and researchers to pursue innovative pathways toward sustainability in the on-the-road transportation sector trying to interpret this concept on the three requested dimensions, social, economic and environmental. Within this framework, hydrogen–methane mixtures have emerged as a promising alternative fuel solution which in someways match the three expectations. Hydrogen is characterized by carbon-free combustion, while methane is a comparatively clean and widely available fossil fuel. When blended, these two fuels can lower overall emissions relative to the use of pure methane, while still being compatible with existing internal combustion engines. This compatibility makes the adoption of such blends
Di Battista, Davide, Di Bartolomeo, Marco, Di Prospero, Federico, Di Diomede, Domenico, Cipollone, Roberto
Comparative Analysis of BEV Performance from Simulated Environment and Physical Hardware Platform2026-24-0005To be published on 09/21/2026
The proliferation of simulation environments has accelerated technological progress across various scientific domains by offering a cost-effective and time-efficient framework for data acquisition and analysis. In the automotive sector, high-fidelity modeling of vehicle components and driving scenarios bypasses the logistical constraints associated with hardware procurement and the intensive requirements of large-scale testing infrastructures. However, pre-calibrated or native software models often imply simplified hypotheses, missing relevant aspects of the entire powertrain-to-wheel energy chain. This study presents a comparative analysis of battery performance within a battery electric vehicle (BEV) by synchronizing virtual simulations with experimental hardware at the test bench. The methodology involves the concurrent modeling of the driving environment, the vehicle chassis, and the propulsion system, followed by the execution of identical driving cycles on a physical platform
Sequino, Luigi, Sementa, Paolo, Altieri, Nunzio, Vaglieco, Bianca Maria, Sorrentino, Chiara
Conversion of a 15kW diesel engine to operate in dual fuel mode with hydrogen and diesel2026-24-0014To be published on 09/21/2026
A 15kW diesel engine has been modified in the laboratory to operate in dual fuel combustion mode. The engine is a three-cylinder, displacement of 1 liter, fueled with diesel in its original configuration. It fulfills the emission standard by means of EGR system and three-way catalyst at the exhaust. The first system has been deactivated in the dual fuel operation mode of the engine. The engine has been modified to set three PFI injectors, facing the intake valves, in the intake manifold of the engine. The hydrogen injection is phased with the opening of the valve in the engine combustion cycle by delay units. The diesel injection with the standard ECU has been used as the start of combustion within the cylinder. The engine operation in dual fuel mode has been tested at maximum torque and power of the engine. To achieve the torque/power at several engine speeds both the quantity of diesel by the accelerator pedal position and the quantity of hydrogen adjusting the PFI injectors duration
Mancaruso, Ezio, Rossetti, Salvatore, Cameretti, Maria Cristina
Component Dynamics of a Motorcycle Brake Caliper: Analysis and Experimental Validation of Seal-Groove Mechanics and Controlled Rollback Design.2026-01-0823To be published on 09/14/2026
Pad - Rotor separation is critical to effective braking performance, pedal feel and NVH. In floating brake calipers, this separation is primarily governed by the seal and groove mechanics. Current studies primarily focus on the mechanics through empirical methods on single seal-groove systems for car calipers. However, a significant literature gap exists for motorcycle seal grooves and any system that utilizes a two seal-groove system with a primary pressure seal and a secondary dust seal. Since 75% of automobiles registered in India are motorcycles and Anti-lock braking becoming mandatory from 2026, designing a caliper with precise seal-groove mechanics becomes critical. This study proposes a theoretical framework by modeling the seals as a shear-beam and predicting the rollback using stick-slip hysteresis and resistive forces of the piston. Experimental validation was performed on three production motorcycle calipers, with the measured rollback and the piston push following the
Vaitheeswaran, Gyaneshwar, N, Manoj, M, Mahesh, Yogesh, Deepak, Rai, Ashutosh
Optimization of Hydraulic Disc Brake Caliper Parameters to Achieve Near Zero Residual Drag in Two-Wheeler Brake Systems2026-01-0820To be published on 09/14/2026
Residual drag in hydraulic disc brake systems is an inherent phenomenon caused by elastic deformation of piston seals, geometric tolerances, and frictional interaction between piston, seal, and brake pads. Even minimal unintended pad-to-disc contact after brake release can generate residual torque, leading to increased rolling resistance, temperature rise, accelerated pad wear, and reduced vehicle efficiency. With growing emphasis on performance optimization and energy efficiency in two-wheeler applications, minimizing brake drag without affecting braking response has become an important design objective. This paper presents the design, analysis, and experimental validation of a zero-drag floating brake caliper concept developed to reduce residual brake torque through optimization of piston seal characteristics and groove geometry. The study focuses on understanding piston rollback behavior as the primary mechanism governing pad clearance after pressure release. Analytical evaluation
Badade, Ashish Laxman
Influence of Caliper Piston Wall Thickness and Hard Anodizing on Thermal Transfer and Seal Rollback Stability in Hydraulic Disc Brakes2026-01-0822To be published on 09/14/2026
Thermal stability and sealing reliability are critical performance parameters in hydraulic disc brake systems, especially under high-energy braking conditions where elevated temperatures directly influence brake fluid behavior and elastomer seal durability. Lightweight design trends increasingly encourage reduction in caliper piston wall thickness to optimize mass and response characteristics; however, such modifications alter the thermal conduction path and transient heat distribution within the piston–seal interface. This study investigates the combined effect of 50% reduction in aluminum caliper piston wall thickness and increase in hard anodizing thickness from 20 µm to 50 µm on heat transfer characteristics and piston seal rollback consistency. A comparative analytical and experimental approach is adopted to evaluate thermal resistance changes due to variation in anodic oxide layer thickness and piston geometry. One-dimensional thermal modeling is correlated with controlled
Badade, Ashish Laxman
Precise Simulation and Test Closed-Loop Verification of Drag Torque for Brake Caliper of In-Wheel Electric Motor2026-01-0813To be published on 09/14/2026
Aiming at the industrial pain points of high control difficulty of drag torque, low precision of traditional simulation and lack of authoritative test closed-loop verification for the special brake caliper of in-wheel electric motor, taking the YF3501S73 front brake caliper and YF3502S73 rear brake caliper as the research objects, a high-precision finite element simulation method coupling the nonlinearity of piston seal material with bilateral parallel return springs was proposed, and the simulation boundary conditions were calibrated by finely matching the bench test working conditions. To ensure the authority and engineering practicability of the research results, the drag torque bench test was carried out in strict accordance with QC/T 592-2013 Performance Requirements and Bench Test Methods for Hydraulic Brake Caliper Assemblies, and in alignment with the international brake drag test specifications of SAE J2923 and JASO C448, thus realizing a complete closed loop of simulation
Liu, Yuqi
A Study on the Development of Brake Moan for CTBA Vehicles Using Simulation2026-01-0814To be published on 09/14/2026
Not only are customers' expectations for the development of various products, but also the demand for emotional quality improvement of the products is steadily increasing. Brake NVH, which is generated during vehicle braking, has a lot of influence on the emotional aspects of customers. There are several brake NVH such as judder, squeal, and moan. First, judder is phenomena of handle, brake pedal vibration and noise that occur during braking at the high-speed. The quality of judder has been improved a lot by applying judder detection and compensation logic in internal combustion engines and the heat load on the disc is reduced by regenerative braking in electric vehicles. So the judder problem hardly occurs these days. A squeal is a noise generated during braking at a low speed. The squeal is solved by tuning and shape change of a friction material in the high frequency band and by making the robust systems design such as caliper and disc in the low frequency band. Moan noise is low
KIM, SUNGHO, Kim, Jeongkyu, HWANG, JAEKEUN, Kang, Donghoon
Experimental Investigation on Unburned Methanol and Formaldehyde Emissions from a Direct-Injection Diesel / Methanol Dual-Fuel Engine2026-99-1646To be published on 07/24/2026
For large-bore marine methanol / diesel dual-fuel engines, this study investigates the formation characteristics of unregulated emissions through experimental methods and explores the mechanisms by which engine load and injection timing influence the emissions of unburned methanol and formaldehyde. The study was carried out on a supercharged intercooled inline six-cylinder engine, and Fourier Transform Infrared Spectroscopy (FTIR) was used to monitor the exhaust composition in real time. The study shows that methanol released in the exhaust is due to the incomplete combustion of the methanol fuel. In the combustion process of methanol fuel, formaldehyde mainly arises from two pathways, the first of which is the partial oxidation of methanol inside the cylinder; secondly, the unburned methanol in the exhaust gas oxidizes in the exhaust pipe to generate formaldehyde. As the load increased from 25% to 100%, the unburned methanol emissions decreased by 29%, and formaldehyde emissions
Jiang, Yuqi, Li, Hongmei, Zhang, Wenzheng, Li, Xiao, Zheng, Liang, Meng, Yangqian, Gu, Xianan, Hua, Hanqing
Lubrication Design and Experimental Verification of Long-Lifespan Ball Screw for Space Environment2026-99-1635To be published on 07/24/2026
Ball screws, as classic high-precision transmission structures, are widely used in various linear motion mechanisms. To meet the needs of space applications, it is necessary to address issues such as microgravity and long lifespan to enhance the in-orbit lifespan and reliability of ball screws. Traditional oil or grease lubrication methods are often unsuitable for space environments due to microgravity and vacuum evaporation problems. This paper conducts relevant research on lubrication design, friction pair design, and friction and wear verification to solve the lubrication and lifespan issues of long-lifespan ball screws for space applications.
Xie, Wen, Zhao, Jian, Gong, Kang, Hu, Xiaonan, Guo, Menglei, Jiao, Hanyu
Research on the Damage Behavior of the Aluminum Alloy Nozzle Closure in Solid Rocket Motor during the Bursting Process2026-99-1612To be published on 07/24/2026
When the aluminum alloy closure of the solid rocket motor nozzle is opened, tearing occurs at the root of the adhesive surface, which belongs to damage failure under a complex stress state. To help in the prediction and control of blasting pressure and nozzle closure failure morphology, this work designed and manufactured various shapes of 1060 aluminum alloy test specimens, performed damage tests, and calibrated the damage constitutive model parameters. The results gathered were utilized to create a finite element model of the nozzle aluminum alloy closure, and the blasting procedure was calculated. We conducted air pressure explosive tests on closures to confirm the finite element results. The numerical predictions and experimental results are very consistent, and the closure breaks along the adhesive surface. The constitutive characteristics obtained during material testing accurately characterize the closure’s damage process, providing a theoretical framework for the design and
Jia, Kai, Li, Weinan
Modeling and Simulation Analysis of Liquid Hydrogen and Power Systems Based on Amesim2026-99-1608To be published on 07/24/2026
Hydrogen-powered aircraft primarily utilize the conversion of liquid hydrogen into gaseous hydrogen to replace aviation kerosene, where hydrogen is directly combusted to provide propulsion. This study applied Amesim software to establish a complicated model simulating the liquid hydrogen to gaseous hydrogen conversion and ignition combustion processes. The simulation contains converting liquid hydrogen into gaseous hydrogen through a heat exchanger and simulating the mixture of gaseous hydrogen and air in the engine combustion chamber, and then igniting the mixture. The pressure, temperature, and flow rate of gaseous hydrogen and air during the ignition and combustion process in the engine combustion chamber, as well as the outlet temperature of the combustion chamber, are simulated and analyzed. The results demonstrate that during the simulation process, the internal pressure of the liquid hydrogen storage tank, the outlet pressure and flow rate of the liquid hydrogen pump, and the
Gao, Pengfei, Wang, Lijian
Simulation and Analysis of the Ignition Flow Field at the Bottom of a Small Cartridge with Densely Packed Granular Propellant2026-99-1609To be published on 07/24/2026
To address the issue of point ignition efficiency caused by the dense packing of granular propellant in miniaturized ejection devices, this study determined that the ignition efficiency at the bottom of the small cartridge is sufficient to meet requirements. By combining the Blender physics engine with ANSYS SpaceClaim scripting and modeling technology, a three-dimensional random packing model was constructed. Fluent fluid-structure interaction simulations analyzed the effects of vertical, horizontal, and mixed drop methods on ignition characteristics. The Realizable k-epsilon turbulence model was used to simulate the transient flow of high-pressure gas, quantifying ignition efficiency by the fuel surface ratio. At a certain ignition pressure, it was found that the fuel surface ratio growth rate for vertical and mixed drop filling methods was higher (with differences < 3% within 0.25 ms). Further analysis indicated that horizontal drop filling led to an 8.7% reduction in the internal
Yu, Rui, Wang, Xiaojun, Bai, Liqiang, Li, Guoqin
Research on a Rocket Projectile Impact Point Prediction Model Based on Improved Proportional Navigation Guidance Law2026-99-1602To be published on 07/24/2026
Rocket projectiles are a type of ammunition that get their power from rocket engines. Long-range guided rockets, in particular, hold great significance as they seem to mark the way forward in modern warfare. These guided projectiles take full advantage of the considerable range that long-range rockets offer and, at the same time, manage to achieve improved accuracy. This paper delves into a model that is used for predicting the impact point of rocket projectiles, with the application of the proportional navigation guidance law. It also undertakes an analysis of both the strengths and the weaknesses of this model. Through the formulation of equations related to the dynamics of the center of mass and some other supplementary equations, a rather comprehensive trajectory equation was worked out. When this trajectory was simulated, it brought about the creation of a firing table, which is of help in predicting the initial trajectory inclination angle.
Tao, Wenwen, Wang, Ru, Zhang, Liang, Pi, Runge
Alignment Control of an Aerial Wireless Power Transmission Device2026-99-1622To be published on 07/24/2026
With the development of battery technology and wireless power transmission technology, their applications in the aviation field have broad prospects. Alignment control is the key to achieving wireless power transmission in the air. This paper first establishes a mathematical model for the proposed wireless power transmission device, decomposes and simplifies it to obtain a controlled object model that is more suitable for the algorithm in this paper. Aiming at the accuracy of alignment control in the task, a fused dynamic inverse algorithm with feedforward optimization was designed step by step and verified through simulation. In the simulation, typical application scenarios were designed in combination with the requirements of wireless power transmission technology. The results show that compared with the general dynamic inversion algorithm and differential feedback-fused dynamic inverse algorithm, better alignment control effects have been achieved, and this algorithm can achieve
Tan, Xudong, Hei, Wenjing, Lei, Yidi
Research on the Inter-Stage Energy Transfer System of Launch Vehicles Based on Multi-Channel Coupling Mechanisms2026-99-1619To be published on 07/24/2026
In the paper, a novel non-contact high-power energy transfer system based on a layered coupling structure is designed to meet the demand for reliable energy transmission during the inter-stage separation process of launch vehicles. The system adopts the upper four-coil transmitting array and the lower single-coil receiving structure and combines the innovative design of a 6:1 step-down transformer topology. Through the optimization of the multi-channel magnetic field coupling mechanism, the system realizes the safe transmission of more than 2 kW of power in close interstage under the difficult problem of transmission loss under the scenario of low input voltage and high output current, which effectively solves the problem of the system. Experimental findings can demonstrate that with a specified input voltage, the system could keep its output voltage of about 28 V under a given input voltage, and the maximum output current reaches about 85 A. The transmission efficiency is
Guo, Xinwen, Jing, Xiaorong, Xu, Pengfei
Design and Application of A Pressure Measurement System Based on Spacecraft Chemical Propellant Engine Plume Test2026-99-1623To be published on 07/24/2026
Spacecraft with chemical propellant engines, especially spacecraft for exploring extraterrestrial objects, need to carry out plume tests on the ground in order to determine the influence of engine plumes on spacecraft. An important purpose of the plume test is to accurately measure the pressure field in key parts of the spacecraft. In this paper, according to the pressure measurement requirements of the spacecraft plume test, the design of a pressure measurement system is carried out, which mainly includes a pressure measurement sensor, a pressure difference measurement sensor, a pipeline, a cable, a measuring instrument, a data acquisition instrument, upper measurement software, and so on. The designed pressure measurement system was successfully applied to the plume impact test of Chang'e VII, which provided important technical support for the development of the spacecraft.
Wu, Yue, Guo, Qinliang, Wu, Dongliang, Liu, Xiaoning, Tao, Dongxing, Lin, Boying, Xie, Zheng, Wei, Xi, Niu, Tong
Fatigue Life Analysis of Diesel Engine Filter Seat under Random Vibration Condition2026-99-1656To be published on 07/24/2026
3.067
Gu, Kexuan, Zhu, Yi, Xie, Liang, Wang, Wei
Analysis of the Cause of Knocking Noise in a Marine Dual-Power Dual-Branch Transmission Gear System2026-99-1650To be published on 07/24/2026
This study investigates the knocking noise phenomenon in a marine dual-power dual-branch transmission gear system. Vibration mechanisms are analyzed, and potential failure modes are assessed. System vibration data were evaluated using time-domain and frequency-domain methods. Results show that overall vibration levels remained within acceptable limits, with no indication of imminent failure. Physical inspection confirmed that the shaft, gears, bearings, housing, and installation met specifications, with no observed performance degradation or structural damage. By correlating noise occurrence with vessel loading conditions, a strong relationship was identified among gear transmission torque, the power distribution ratio between high-and low-pressure turbines, and the onset of knocking. Specifically, under low-load conditions, uneven power and torque distribution among the four gear branches led to insufficient loading on the low-pressure side. This light-load state induced instability
Gu, Chengzhong, Xu, Hanwei, Luo, Rirong, Ren, Fushan
Design and Dynamic Simulation of a High-Speed Conjugate Parallel Indexing Cam Mechanism2026-99-1625To be published on 07/24/2026
The cam mechanism, as an extremely important transmission method in mechanical transmission, is widely used in automatic machinery and automatic control devices. In small and medium-sized high-speed automatic guns, high-speed camshafts are often used to achieve intermittent movement of the supply and transport of ammunition during high-speed shooting. Due to the possible vibrations, wear, and instability that may occur during the movement of high-speed camshafts, the design of camshafts needs to meet the requirements of continuous third-order derivatives of the curve, while minimizing angular acceleration as much as possible. This article focuses on the design requirements of a high-speed intermittent motion mechanism, with continuous angular velocity and angular acceleration as design constraints. It establishes segmented function motion equations for the acceleration, deceleration, and uniform speed sections of a high-speed conjugate parallel indexing cam while ensuring that the
Wang, Shuman, Qin, Yanhui, Ning, Bianfang
A Detection Method for 10N Thruster Ignition Anomaly Based on the Temperature Model2026-99-1814To be published on 07/17/2026
To solve a problem that ignition anomaly can’t be detected in time, based on the thermal equilibrium equation, the space heat flow, heater heating, propellant combustion, and thermal radiation to cryogenic space are considered to build an accurate ignition temperature method for the 10 N thruster by using on-orbit true temperature. Further, considering the error of measuring the thermistor, an envelope model for the 10 N thruster ignition temperature is established. Based on the above, a detection method for the 10 N thruster ignition anomaly of on-orbit satellites is proposed. The accuracy of the method is relatively high, and the absolute error is less than 3 degrees Celsius. An anomaly can be quickly detected when the 10N thruster ignition temperature deviates from the normal trend by 3–5 degrees celsius. The method is applied to a DFH-3 satellite, and the maximum difference of 10 N thruster ignition temperature between the theoretical values calculated by the proposed method and
Li, Liling, Tian, Huadong, Wei, Yubo, Fei, Di, Xing, Chao
Research on the Protection Design of Flexible Cables for Civil Aircraft2026-99-1828To be published on 07/17/2026
Flexible cables are widely used in aircraft and are essential for ensuring the proper functioning of critical systems and flight safety. The design and validation of these cables represent a foundational technology in enabling the transmission of electrical power and signals throughout the entire aircraft. To achieve their intended service life, appropriate protective measures and experimental verification must be implemented. Drawing on the development experience of flexible cables for a specific domestic aircraft model, this paper proposes a combined protection method designed to extend the service life of flexible cables. Experimental analysis demonstrates the practicality and reference value of this approach.
Shi, Liqing, Hu, Huanghua, Ge, Zengwen
Study on Diesel-Methanol Non-Premixed Combustion Characteristics of a Marine Dual-Fuel Engine at Different Methanol Substitution Rate2026-99-05177/10/2026
Methanol use in marine engines has the potential to reduce nitrogen oxide emissions, particulates, and greenhouse gas emissions. A turbocharged four-stroke marine diesel powerplant was converted to run as a double-DI (direct injection) diesel-methanol hybrid engine. Experimental studies using a non-premixed combustion scheme showed that higher methanol substitution ratios (MSR) led to increased peak heat release rates. The combustion process displayed distinctive two-phase behaviors. Increasing MSR caused retarded ignition timing, shortened combustion duration, and improved thermal efficiency. Combustion stability was significantly improved at higher MSR. Emissions results showed NOX and HC were increased in proportion to MSR, whilst particulate emissions and CO concentrations were inversely reduced. Methanol enrichment was found to enhance NOX and HC formation processes but also accelerate soot particulate decomposition and CO oxidation mechanisms.
Li, Xiao, Jiang, Yuqi, Yan, Ping, Zheng, Liang, Li, Hongmei, Zhang, Wenzheng, Chen, Chao, Man, Zhongguo
Researchon Key Technology Optimizationof Automotive Magnetic Continuously Variable Transmission2026-99-05097/10/2026
Traditional mechanical continuously variable transmission (CVT) has a complicated structure. During the transmission process, the master and slave wheels rub against each other to produce chattering and heat loss, and the master and slave wheels are seriously worn. In order to improve the transmission efficiency and reliability of continuously variable transmission, Automotive magnetic CVTs (Manetti Continus, Livaria, Breitlans, Mack) were used as research objects. By establishing the efficiency model of key parts, the relationship between the efficiency of each component and different parameters is transformed and calculated, and then it is optimized using Matlab. The finite element analysis of a permanent magnet eddy current speed regulating device is carried out by using finite element Ansys Maxwell, and the relationship curve between the average meshing area and each parameter is analyzed. The results show that the volume of the optimized gear train is reduced by about 51.7
Zhou, Dan, Zhang, Bolin
Optimization of Preheating Energy Distribution for Low-Temperature Cold Starts in Diesel-Electric Hybrid Vehicles2026-99-05167/10/2026
To minimize energy input and preheating time, this study first analyzed the energy consumption of intake air, lubricating oil, and coolant preheating through simulations. Temperature rise data were collected under various heating parameters. Next, simulations evaluated the hybrid power system’s resistance characteristics immediately after startup and the combustion parameters during the first cycle post-ignition under different temperatures. The temperature thresholds for successful start-up were identified, defining the feasible domain for optimization. Optimization calculations aimed to minimize preheating time and energy input, constrained by maximum preheating power. Results show that intake air heating has the greatest impact on start-up success, followed by lubricating oil heating. It is recommended to increase energy allocation to intake air and lubricating oil heating. This optimized strategy reduces preheating time and energy input by approximately 26% without changing the
Wei, Shengchen, Zhao, Zhenfeng
Simulation Analysis of Pure Electric Vehicle Equipped with Continuously Variable Transmission2026-99-05227/10/2026
This study looks into the performance traits of a pure electric car that has a continuously variable transmission (CVT) system by doing careful simulations. The research is mostly about checking how well it performs dynamically and how much better its energy efficiency is compared to regular designs. With the help of AVL Cruise software, a detailed drivetrain model was made to test things like how fast it can accelerate, its top speed, how well it climbs hills, and how much energy it uses when driven in standard ways. The simulation results show some big improvements: the CVT car can go from 0 to 100 km/h in 12.92 seconds, which is 14% quicker than expected; it can reach a top speed of 179 km/h, 15% higher than planned; and it can climb really steep hills at a 41.33% gradient. The energy efficiency analysis also found that it uses less power, consuming just 15.88 kWh per 100km under NEDC conditions and 13.72 kWh per 100km in UDC cycles, which are 21% and 24% less than before. These
Chen, Haishan, Gong, Naifa, Pan, Yulong, Cai, Zhicheng, Gao, Yujie, Shen, Xiaobing, Fu, Xianlan, Chen, Keren
Temperature Control Technology for Solid-state Hydrogen Proton Exchange Membrane Fuel Cell2026-99-05287/10/2026
The global trend towards green and low-carbon development is that hydrogen fuel cells, as a new type of green power device, have the characteristics of zero emissions and no pollution. Its basic principle is that hydrogen fuel directly converts chemical energy into electrical energy through electrochemical reactions, achieving energy conversion between fuel cells and internal combustion engines, thereby providing sustained and stable power. The PEMFC has attracted significant attention due to advantages such as fast start-up times and long lifespans. However, excessive temperature during the reaction process of solid-state hydrogen proton fuel cells can lead to a decrease in efficiency. This article studies the temperature control device of solid-state hydrogen fuel cells and finds that active temperature control technology can achieve precise temperature regulation, but it consumes more energy; the passive temperature control scheme can reduce energy consumption, but the response
Ma, Yueyue, Liu, Jingyi, Shi, Jian, Lu, Zhaona, Bao, Xueqin
Review of Power Management Technology for Turbine Hybrid Electric Propulsion Systems2026-99-05317/10/2026
The turbine hybrid electric propulsion system is an important form of green aviation. Unlike the single form of aviation power scheme, the hybrid energy system is flexible in architecture, uses two or more energy forms, and has diverse energy sources. Under different mission requirements, it needs to meet the requirements of mass balance, energy balance, and power demand, etc. Therefore, The control and distribution management between different energy systems have become the key to hybrid power, and power management technology is one of the key challenges in the development of aviation hybrid power control systems. This paper reviews the current structural forms of aviation turbine hybrid electric propulsion systems, analyzes the current research status of power management technology for aviation hybrid systems, and points out that the online power management method based on optimization is the best power management technology solution for turbine hybrid electric propulsion systems
Cai, Changpeng, Liu, Hao, Gu, Jiangwei, Li, Shunming, Zhang, Haibo
Analysis and Improvement of Rattle Noise in Manual Transmission2026-99-05277/10/2026
In response to the problem of manual transmission rattle noise in the acceleration process of a truck, the mechanism of the problem is analysed, and the scheme is developed and verified from two aspects: reducing the torsional vibration of the system and reducing the response of the transmission gear. The results show that, on the one hand, reducing the clutch stiffness and optimizing the torsional vibration of the system can reduce the rattle noise of the transmission; On the other hand, it can also reduce the rattle noise of transmission gears by improving the engagement precision of transmission gears and reducing the gear clearance. Considering the improvement effect, cost, and influence on other performance of the two schemes, the appropriate engineering scheme is selected to effectively solve the problem and improve the riding comfort of the product.
Yang, Zhijie, Xu, Binghua
Influence of Eccentric Chamfer Structure at Seat Ring Bottom Hole on Swirl Ratio and Flow Coefficient in Dual-Tangential Intake Ports2026-99-05247/10/2026
The airflow characteristics of engine intake ports significantly influence combustion efficiency and emission performance. This study investigates the effects of an eccentric chamfer structure at the seat ring bottom hole on the swirl ratio and flow coefficient in a dual-tangential intake port for a four-valve diesel engine. Computational fluid dynamics (CFD) simulations and steady flow experiments were conducted under valve lifts ranging from 1 mm to 9 mm. Results indicate that the eccentric chamfer structure enhances the swirl ratio by 39 times (from 0.12 to 4.73) at low valve lifts (<6 mm) without compromising the flow coefficient. At higher lifts (>6 mm), both chamfer designs exhibit negligible differences in performance. Experimental validation confirmed the CFD results, with errors below 3% for swirl ratio and 5% for flow coefficient. This work provides a practical approach to optimize low-speed engine performance through geometric modifications.
He, Shuchao, Li, Ying, Shi, Yanfei
Research on the Dynamic Simulation Method of Gearbox Based on ADAMS and MATLAB2026-99-05197/10/2026
The gearbox is a key component of the mechanical transmission system, and its fault diagnosis is essential to the reliability of the equipment. However, obtaining fault samples under actual working conditions for gearbox fault diagnosis is challenging. In this paper, the rigid-flexible coupling dynamic simulation model of the gearbox is established, and the co-simulation of gear normal, crack, and breakage is carried out in the ADAMS and MATLAB environments. The comparison between the simulated and measured signals shows that the simulation method can accurately reflect the key characteristics, such as rotation frequency and meshing frequency, and verify its reliability and accuracy. The research results can provide effective data support for gearbox fault diagnosis and improve the operational safety of mechanical systems.
Li, Dongxiao, Zhang, Qianqi, Zhang, Zhongzheng, Li, Yongbo
A Multiphysics Approach to Mitigate Pulse-Width-Modulation-Induced Acoustic Noise in Permanent Magnet Synchronous Motor Drives for Electric Vehicles14-15-03-00147/3/2026
This article investigates high-frequency noise in permanent magnet synchronous motors (PMSMs) for electric vehicles, originating from pulse width modulation (PWM). A theoretical model is developed to formulate the phase voltage under space vector PWM (SVPWM), explicitly accounting for the additional harmonic components generated by the discrete-time voltage update in digital control systems. This derived voltage waveform serves as the excitation source in an electromagnetic finite-element model, from which the PWM current harmonics and their resulting high-frequency electromagnetic forces are computed. Critical components of the electromagnetic force are then extracted through two-dimensional Fourier transform. A structural model of the motor, incorporating practical assembly constraints, is established and validated by experimental modal tests on a fully assembled motor unit. To enable rapid noise prediction over the wide speed range, vibro-acoustic transfer functions are introduced
Lin, Fu, Chen, Yihui
A Methodology for the Conversion from Physics-Based to Ultrafast-Running Data-Driven Powertrain Models for Real-Time Applications03-19-04-00177/3/2026
The virtualization of powertrain systems is a key enabler for modern powertrain development. While physics-based 0D/1D simulation models provide accuracy and interpretability, these models are typically computationally demanding, prolonging the development process and usage throughout the V-cycle. Moreover, achieving real-time-capable simulation models through model simplifications remains challenging, as it often leads to significant losses in accuracy. In contrast, data-driven approaches can achieve high computational efficiency without significantly compromising model accuracy. This opens the possibility for not only online control applications, such as model predictive control or reinforcement learning, but also for computational expensive offline control prototyping using ultrafast-running data-driven digital twins. This work focuses on the elaboration of a scalable methodology for the development of ultrafast-running powertrain models for stationary and transient engine operation
Weller, Louis, Zanelli, Alessandro, Yang, Qirui, Brutsche, Martin, Grill, Michael, Kulzer, André Casal
Helicopter Engine-Rotor System CompatibilityARP704A (Current)7/2/2026
This SAE Aerospace Recommended Practice (ARP) recommends a methodology to be used for the design, analysis and test evaluation of modern helicopter gas turbine propulsion system stability and transient response characteristics. This methodology utilizes the computational power of modern digital computers to more thoroughly analyze, simulate and bench-test the helicopter engine/rotor system speed control loop over the flight envelope. This up-front work results in significantly less effort expended during flight test and delivers a more effective system into service. The methodology presented herein is recommended for modern digital electronic propulsion control systems and also for traditional analog and hydromechanical systems.
S-12 Powered Lift Propulsion Committee
Biofuel Effect on Regeneration Capability and Soot Reactivity in SCRoF Systems2026-01-07507/1/2026
Biodiesel blends (B7, B20, B100) were evaluated in a Stage V-compliant SCR on Filter (SCRoF) system for heavy-duty applications to quantify soot reactivity and filter regeneration capability. Compared to conventional diesel (B7), B20 showed slightly faster regeneration performance under real-driving conditions, while B100 resulted in reduced particulate formation and higher soot reactivity, with more intense exothermic events requiring careful management. These differences are attributed to the distinct physical-chemical properties of the fuels (oxygen content, lower heating value) and their interaction with Diesel Oxidation Catalyst (DOC)/SCRoF. All tests were conducted on an engine dynamometer with a Cursor 9 FPT (Fiat Powertrain). Findings are discussed in the context of EU Stage V limits and practical control strategies for heavy-duty applications.
Costa, Simone
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