Browse Topic: Power and Propulsion

Items (64,328)
Find
Feasibility study on the mechanical adjustment of the vibration behaviour of a powertrain test rig for validating longitudinal vehicle shuffle2026-01-0735To be published on 07/01/2026
Vehicle manufacturers use Hardware-in-the-loop (HiL) approaches to validate overall vehicle characteristics, including those dependent on the powertrain, at an early stage of vehicle development. A powertrain test rig is a typical example. In the specific setup, the vehicle engine and side shafts are mechanically coupled to the load machines of the test rig, eliminating the physical influence of the rims, tires and vehicle body. Adapting a specimen to the test rig changes some characteristics. This affects the specimen's vibration behaviour, making it more challenging to validate comfort-related characteristics. A particular example is longitudinal vehicle shuffle; the powertrain's first torsional natural frequency causes it. The natural frequencies of the real vehicle and device under test differ significantly, so a road-matching approach is not directly feasible. To account not only for tire-road contact but also for the missing vehicle mass, some scientific studies propose a purely
Hübner, Carl, Prokop, Günther
Experimental Investigation into Port Water Injection on the Transient Behavior of a Heavy-Duty Hydrogen Engine2026-01-0743To be published on 07/01/2026
Hydrogen-fuelled internal combustion engines are a potential carbon-free propulsion solution for high-power applications such as construction machinery and heavy-duty commercial vehicles. However, compared to conventional diesel engines, hydrogen engines exhibit limitations in transient operation and at full load, primarily due to the high reactivity of hydrogen. In spark-ignited hydrogen engines, combustion anomalies represent the main constraint during performance-oriented operation, particularly during transient phases that require mixture enrichment to meet dynamic torque demands. Water injection is investigated in this study as a means to mitigate these limitations. The paper describes the implementation of a port water injection system on a heavy-duty commercial hydrogen engine and evaluates its influence on engine performance with a focus on transient operating conditions. A combustion anomaly evaluation method developed in-house is applied to quantify the effect of water
Schneider, David, Christoforetti, Paul, Kappacher, Peter, Kapeller, David, Schutting, Eberhard, Eichlseder, Helmut, Trapp, Christian
Experimental study of warm-up and startability operations in a spark ignition engine fueled with ethanol gasoline blends2026-01-0738To be published on 07/01/2026
Thermal transients during warm-up phase influence fuel consumption and combustion stability. Moreover, during engine warm-up, tailpipe emissions are the highest since the catalytic converter has not reached the light-off temperature yet. Therefore, reducing warm-up time would be beneficial for both performance and emissions. In this work, an experimental investigation is carried out on a naturally aspirated four-cylinder spark ignition engine with a displacement of 1.2 liter, equipped with a port fuel injection system. The study compares conventional gasoline with an E30 (i.e. 30% ethanol in gasoline). Tests are performed starting from cold engine conditions and stopped when a fully warmed state is reached. The experimental campaign is conducted at a fixed operating condition of 2000 rpm and 20 Nm load, representative of typical warm-up operation. The analysis focuses on the warm-up duration, defined as the time required to reach steady thermal conditions, and on engine performance
Falbo, Luigi, Falbo, Biagio, Perrone, Diego, Castiglione, Teresa
Synergistic Integration of Advanced Combustion and Air-Path Technologies to Maximize ICE Efficiency in Hybrid Applications2026-01-0733To be published on 07/01/2026
This work investigates the efficiency potential of reciprocating internal combustion engines (ICE) for light-duty vehicle propulsion within the current state of the art and a five-year technological horizon. A validated one-dimensional engine model was extended to integrate multiple advanced technologies, including active prechambers for ultra-lean gasoline combustion, thermal coating, an electric turbocharger capable of supplementary turbine work recovery, variable compression ratio, and variable valve timing implementing a Miller cycle. These enhancements are systematically evaluated to explore their individual and combined effects on engine performance and efficiency. Parametric studies quantify the influence of heat transfer, air–fuel ratio, compression ratio, and other key variables on engine output, enabling the generation of enhanced engine performance maps. These maps reflect synergistic interactions between parameter sets and serve as predictive tools for assessing optimized
Pla, Benjamin, Dolz, Vicente, Serrano, Jose R., Gómez-Vilanova, Alejandro, Oliva, Fermin, Cardenas, Maria, Ariztegui, Javier
Efficient Powertrain Control via Stochastic Signal Decomposition: Utilizing ARIMA Constituents for Real-Time knock detection in Internal combustion engines.2026-01-0737To be published on 07/01/2026
Knocking combustions in an Internal Combustion engine (ICE) are engine damaging combustions and hence reliable detection of every knocking event is very important. Engines typically rely on piezo-electric knock sensors to monitor structure-borne noise; which outputs a complex, continuous time series signal, thus differentiation of knocking vs knocking signal (signal to noise ratio) is difficult without computation intense signal processing such as Fast Fourier Transforms(FFT) or Wavelet transforms followed by manual calibration. In this research we propose an alternative to replace traditional knock detection with more reliable time-domain alternative using Autoregressive Integrated Moving Average (ARIMA) technique. Here we decompose the raw sensor signal into seasonality, trend and residue, and analyze the residue signal to differentiate knocking or non-knocking combustion, as the residual component is seen to retain abnormalities in the signal during knocking combustion. Further
Parulekar, Tushar A., Chilukuri, Sandeep, Mahmood, Haneefa
Design and Prototyping of a winding reconfiguration system for electric traction applications2026-01-0730To be published on 07/01/2026
Battery electric vehicles (BEVs) place high demands on electric drives across a wide operating range: high efficiency in customer-related driving scenarios and maximum performance in dynamic driving modes. A promising solution to this challenge is the dynamic reconfiguration of the electric machine winding configuration between series and parallel mode, enabling optimal electromagnetic properties of the drive for different operating points. This paper presents the design and prototyping of an electronic winding reconfiguration system for high-performance traction applications. Unlike mechanical switching concepts, which have long transition times and cannot switch under load, the proposed system enables fast and safe load transitions between the winding configurations. The study describes the topology and hardware of the switching unit, including the integration of power semiconductors, the required connection assemblies, cooling concept and the control of the power electronics. A
Oestreicher, Raphael, Schneider, Jörg, von Ohlen, David, Fuchs, Patrick, Kulzer, André Casal
Multiphysical modeling of a direct-cooled litzwire winding for a PMSM using surrogate models2026-01-0731To be published on 07/01/2026
In permanent magnet synchronous machines (PMSMs) ohmic losses occur in the stator windings. Reducing these losses contributes to a higher efficiency and increases the vehicles range. An effective approach to reduce frequency-dependent AC conduction loss is the use of litz wires. In addition, direct cooling helps to reduce DC conduction loss and winding temperatures. Therefore, this work presents a multiphysical modeling approach of a direct-cooled litz wire winding in a PMSM. It combines loss modeling of the winding with novel thermal and hydraulic calculation methods. AC conduction loss due to skin and proximity effect and DC conduction loss are modeled temperature dependent. Scaled-down conjugate heat transfer simulations are used to determine the heat transfer coefficient (HTC) between wires and coolant. Additionally, the pressure drop is derived and converted into parameters for use in a porous media model. The derived parameters are used to generate surrogate models to enable
Blaschke, Wolfgang Maximilian, Mengoni, Leonard, List, Adrian, Kulzer, André Casal
Numerical Analysis of Directly Injected Hydrogen into a High-Pressure Chamber2026-01-0745To be published on 07/01/2026
Due to the historical use of fossil fuels, the transportation sector has been one of the major producers of greenhouse gas (GHG) emissions and harmful pollutants. Because of its high specific energy content and the potential for zero carbon-based emissions, Hydrogen Internal Combustion Engines have emerged as an option for decarbonizing heavy-duty transportation. However, injecting high-pressure gas into pressurized combustion chambers induces complex compressible flow phenomena, including choked flow and under-expanded supersonic jet structures, which challenge conventional modeling approaches. Accurate prediction of the resulting fuel-oxidizer mixing process is critical for optimizing engine performance and emissions. This study conducts a numerical investigation of transient hydrogen injection into a high-pressure argon environment, benchmarking a 2D axisymmetric Computational Fluid Dynamics (CFD) model against high-fidelity experimental optical measurements. Utilizing Ansys Fluent
Castilla Batun, Uriel Isaac, Alzahrani, Fahad
Improved Thermal Management for Operating a Battery Electric City Bus under Real Driving Conditions2026-01-0758To be published on 07/01/2026
The goal of reducing the global CO2 emissions requires actions especially for the transportation sector. To achieve the goal, electric traction motors are frequently implemented in passenger vehicles as well as in commercial vehicles like heavy-duty trucks or buses. Particularly electric city buses have the potential to reduce the local emissions in urban areas and provide local exhaust-emission-free mobility. While their number of registrations rises, research focusses on the improvement of the overall system in order to increase the energy efficiency. High importance is gained by the thermal management of the whole system. This research describes and investigates a simulative approach to improve the thermal management and therefore the energy efficiency of an electric bus system. The different thermal components of an electric city bus like drive system, battery system and heating, ventilation and air conditioning system (HVAC system) are modelled. Their thermal behaviour has been
Schäfer, Henrik, Hellberg, Tobias, Meywerk, Martin
Integrated DC Boost Charger in Post-800V Architecture with Open-End Winding Machine – Magnetic-Domain Modelling and Torque Analysis2026-01-0739To be published on 07/01/2026
Next-generation powertrain architectures proposed within EU Horizon projects adopt operating voltages above 800 V, providing improvements in efficiency as well as reductions in copper usage and system weight. However, post-800 V vehicles must remain backward compatible with existing 400 V and 800 V charging infrastructure, which requires the installation of an additional onboard DC boost charging unit on the vehicle. This paper proposes an integrated DC boost charging solution that reutilizes the open-end winding electric machine and the traction inverter of the electric powertrain, enabling backward compatibility while further reducing system cost and weight. In charging mode, the electric machine is repurposed as a passive inductive component, imposing a strict requirement of stationary operation with zero torque generation, which fundamentally differs from the driving mode characterized by rotor rotation and electromagnetic torque production. Consequently, conventional electric
Wang, Haoran, Kallur-Krishnamoorthy, Rajesh, Neuhaus, Christoph, Andert, Jakob
NOx Formation Characteristics of Lean Hydrogen Combustion: From 0D Analysis to Comprehensive 3D-CFD Engine Investigations2026-01-0732To be published on 07/01/2026
The transition toward climate-neutral transportation requires powertrain concepts that combine high efficiency with low pollutant emissions. In this context, hydrogen-fueled internal combustion engines represent a promising solution when hydrogen is produced from renewable energy sources. Owing to its specific molecular properties, hydrogen offers new possibilities for influencing and optimizing the combustion process and reducing the emission formation. This paper presents a numerical approach for characterizing the NOx formation in a single-cylinder research engine equipped with port fuel injection and a passive pre-chamber ignition system. The single-cylinder is operated over a wide range of engine loads and speeds, covering air-to-fuel ratios from λ=1.5 to 2.5 and achieving up to 23 bar indicated mean effective pressure. The study focuses on the influence of engine load and mixture composition on NOx emissions. A dedicated look-up table approach in combination with several reaction
Gal, Thomas, Vacca, Antonino, Chiodi, Marco, Schmelcher, Robin, Kulzer, Andre Casal
Numerical Analysis of Pre-Ignition Factors in Hydrogen Engines2026-01-0740To be published on 07/01/2026
Numerical analysis was conducted to investigate abnormal combustion, a major challenge in efforts to improve hydrogen engine efficiency. Focusing on two factors that induce abnormal combustion—surface reactions and lubricating oil—numerical analysis examined the potential for each to trigger abnormal combustion. Furthermore, since it was confirmed that the self-ignition prediction using a detailed chemical reaction mechanism deviates from experiments at temperatures around 800K, attempts were made to improve this issue. As a result, it was confirmed that surface reactions affect the chemical species ratio near the wall surface but have little effect on flame propagation. Regarding lubricating oil, two possibilities were investigated: the lubricating oil itself self-igniting and becoming an ignition source for the hydrogen mixture, and deposits generated from the lubricating oil generating heat and becoming an ignition source. We investigated two possibilities: the lubricating oil
Moriyoshi, Yasuo, Yamane, Taichi, Wang, Zhiyuan, Kuboyama, Tatsuya
Biofuel Effect on Regeneration Capability and Soot Reactivity in SCRoF Systems2026-01-0750To be published on 07/01/2026
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
Multi-Scale Modelling of Localized Battery Degradation in Heavy-Duty Series Hybrids: From Electrochemical Impedance Spectroscopy to Powertrain and Battery Pack Performance2026-01-0747To be published on 07/01/2026
The operational efficiency of heavy-duty hybrid electric vehicles (HEVs) is intrinsically linked to the health and power capability of the battery pack. Traditional battery management systems often rely on bulk State-of-Health (SOH) metrics, failing to account for localized degradation and the resulting current imbalances within parallel-connected modules. Recent literature emphasizes that cell-to-cell variations and thermal gradients can lead to a 6% reduction in accessible energy and a 5.2% acceleration in degradation rates due to heterogeneous current distribution. This study addresses these gaps by presenting a multi-scale modelling framework that translates cell-level electrochemical degradation features into system-level powertrain optimization. Initially, a thorough experimental campaign was conducted on LFP cells, using accelerated cyclic and thermal aging at 25°C and 60°C. High-fidelity battery parameters were extracted from EIS data using fractional-order equivalent circuit
Safavi, Seyed Reza, Homayouni, Hooman, Shoa, Tina, Wang, Jason, McTaggart-Cowan, Gordon
A Comprehensive CFD‑Driven Approach to Battery Thermal Modeling and Cooling System Optimization2026-01-0752To be published on 07/01/2026
In recent years, the thermal management batteries for automotive applications has become a key factor to further improve their performance and ensure their efficiency, durability and safety. As a matter of the fact, an overheat of these devices can result in various issues, including degradation of insulation materials, decreased efficiency, shortened lifespan, and even failure and consequent thermal runaway. In this context, this work aims to improve the comprehension of heat dissipation in batteries and to model the cooling circuit through the integration of CFD, in order to provide guidelines for the optimization of the overall system. To this scope, a novel OpenFOAM solver is introduced, capable of computing electric quantities along with losses inside the battery cells, consequently assessing heat generation across various components. The combined thermodynamic and electric analysis of the battery, which predicts the heat sources and temperature distribution under the effective
Montenegro, Gianluca, Onorati, Angelo, Della Torre, Augusto, Tariq, Muhammad Hasnain, Bonetti, Elisa
Application of Tone-to-Noise Ratio for Early Diagnosis and Control of Electric Drive Whine2026-01-0686To be published on 06/20/2026
High-frequency whine from electric drive systems has become a critical issue restricting the improvement of vehicle sound quality. Traditional evaluation methods struggle to accurately identify masked whine risks in the early research and development (R&D) phase, due to incomplete hardware of prototype vehicles and high interior background noise. This often leads to problems being delayed until the mass production stage, resulting in high rectification costs. To address this issue, this paper proposes and validates an early risk assessment method based on the Tone-to-Noise Ratio (TNR). First, the generation mechanism of Electric Drive (E-Drive) whine is systematically analyzed, identifying the electromagnetic noise of the electric motor and the gear whine of the reducer as the two dominant noise sources. To address this bottleneck, the TNR psychoacoustic metric is introduced to quantify the perceptual salience of tonal noise relative to background noise, which effectively mitigates the
Yun, Zhao, Hui, Hui, Gao, Pan, Xiao, Zhongdi, Zan, Chen, Teng, Charlie
Methodology Development for EDM Vibro-acoustic Assessment using Simulation Measurement Comparison and RCA2026-01-0691To be published on 06/20/2026
The virtual development of Electric Drive Modules (EDM) for Battery Electric Vehicles (BEVs) requires proven and predictive methodologies. One part of the development investigates the vibro-acoustic assessment for low and high frequencies over the targeted operating range. The efficient usage of such a methodology requires the understanding of the accuracy and the validity of the achievable results as well as the derivation of suitable improvement measures for goals that have not been achieved. The usage of reference data from experimental investigations and a detailed root-cause analysis (RCA), to directly link a specific response and behavior to the excitations, modal content and transfer functions, is an essential and non-trivial part of the methodology development. This paper describes the development of such a methodology using the example of a new EDM virtual model for Noise, Vibration and Harshness (NVH) analysis, the simulation approach, validation, and evaluation procedure. It
Klarin, Borislav, Pevec, Denis, Resch, Thomas, Esposito, Sara, D'Alessandro, Vincenzo, Spanu, Giorgio
NVH Design and Refinement of Dedicated Hybrid Engine on Range Extender Electric Vehicle2026-01-0688To be published on 06/20/2026
Traditional NVH (Noise, Vibration, Harshness) refinement is reactive, addressing issues post-prototype. In contrast, this work establishes NVH as the primary driver in early engine development for range extender electric vehicles (REEVs). Customer demands for imperceptible engine operation [1] - intensified by absent masking noise in electrified powertrains [2] - necessitate a proactive methodology: Usage-Driven Operating Profile: Analysis of >500,000 km fleet driving data identified statistically dominant operating conditions. This enables precise NVH focus areas and proactive avoidance-zone definition in the engine operational map. Vehicle-Driven Target Setting: Subsystem-level NVH targets (e.g., <58 dB(A) idle noise → engine-level) were rigorously derived from vehicle imperceptibility requirements and the dominant usage profile. Preventive Design Optimization: Architectural choices (stiffness-enhanced bedplate block), component tuning (crankshaft/flywheel dynamics), and subsystem
Wang, Hao, Zhang, Guiqiang
Investigation of Spline-Induced Excitation Forces in Electric Drive Units via Flexible Multibody Dynamic Simulation2026-01-0692To be published on 06/20/2026
This study investigates the NVH characteristics of the spline coupling that connects the motor and reducer shafts in an electric drive unit, using flexible multibody dynamic simulations. Focusing on the source stage of the NVH analysis process, the excitation force magnitude and spline trajectory are examined under various spline design conditions. The study compares spline fit types (side fit vs. major fit), clearance vs. interference conditions, and variations in tooth number and module size. All spline configurations are designed to meet AGMA safety factor requirements. Side fit splines exhibit lower first-order excitation forces compared to major fit splines, but significantly higher excitation forces at higher orders. This leads to increased spline trajectory amplitude and amplified whirling of the input shaft. Since the input gear is directly coupled to the input shaft, this whirling behavior induces eccentricity in the gear itself. In particular, clearance fit conditions result
Kim, Dong-Jun, Hwang, Seung Gyu, Kim, Donghee, Kim, Seon Hyeong, Lee, SangHan, Grant, George, Halse, Christopher
Vibroacoustic Analysis and Optimisation of an Electric Refrigerant Scroll Compressor2026-01-0722To be published on 06/20/2026
In electrified vehicles, auxiliary units can be a dominant source of noise, one of which is the refrigerant scroll compressor. Compared to vehicles with combustion engines, e-vehicles re-quire larger refrigerant compressors, as in addition to the interior, the battery and the electric motors must be cooled. Various types of excitation in the compressor cause vibrations on the compressor surface and the emission of airborne noise. Fluid dynamic forces resulting from the cyclic compression principle act on flow-conducting components, while alternating forces caused by the imbalance of the eccentrically running compressor scroll or by torque fluctua-tions on the drive shaft are transmitted to the housing via the bearings. In order to identify the sound generation mechanisms in the compressor, the vibrations of the compressor surface were measured using a laser scanning vibrometer and the sound radiation was characterised using a sound intensity probe. This paper illustrates the
Saur, Lukas, Beer, Gabriel, Fritzsche, Marco, Becker, Stefan
Simulation and Analysis of Flow and Acoustic Induced Structural Vibration2026-01-0696To be published on 06/20/2026
For analysing flow and acoustic induced structural vibration, a run time fully coupled framework combining a hybrid CFD-CAA approach with a modal response simulation was validated and presented at the ISVNH 2022 (SAE Technical Paper 2022-01-0938). In this contribution we show the application of this method on a production vehicle, simulating the flow and acoustic induced vibration of the bonnet. The simulation setup of this study resolves the geometry of the vehicle including the complex details of the bonnet structure, the frunk and the engine compartment. The FEM model for the modal analysis of the bonnet takes into account the complex boundary conditions at the bearings and provides the eigenmodes relevant for the low frequency range. Simulations are conducted in an undisturbed wind tunnel setup and the resulting vibrations are compared to acceleration measurements under wind tunnel and road conditions. Due to the employed hydrodynamic acoustic split approach, the relevance of the
Schwertfirm, Florian, Ocker, Joerg, Hartmann, Michael
PSYCHOACOUSTIC ANNOYANCE MODELS ASSESSMENT FOR AUTOMOTIVE FAN-SYSTEMS2026-01-0672To be published on 06/20/2026
Because of automotive electrification, fan systems previously hidden by internal combustion engines could become key contributors to the overall noise behavior. Metrics like overall Sound Pressure Level or Loudness are first order metrics enabling ranking. Yet, second order factors, that are relevant to assess annoyance, are not correctly described using a single criterion. This paper studies the applicability of various Psychoacoustic Annoyance (PA) models in an attempt to address subjective perception of sound quality. Based on pairwise comparison through a jury test with a set of 8 noises at a similar global level, the combined impact of several psychoacoustics metrics was previously determined. This computation includes a signal modulation metric, a frequency content balance and a tonal criterion. To assess this approach, the correlation for fan-system noise annoyance ranking based on its jury test is compared with several PA criteria, starting from initial Zwicker and Fastl model
Scouarnec, Denis, Bennouna, Saad
Spatial Optimisation of Inner Dash Acoustic Performance using Reciprocal Holography2026-01-0712To be published on 06/20/2026
As acoustic requirements for NVH trim components become more demanding – driven by cost, weight, and increasingly, sustainability – there is growing pressure to optimise performance across multiple criteria. In complex components such as the inner dash, performance is often assessed in isolated. However, this fails to reflect real-world conditions, where contributions from ancillary systems, the instrument panel, and variable noise sources such as the power unit, gearbox, and tyres are significant. Traditional Transmission Loss (TL) measurements provide averaged results that can overlook spatial variation and lead to suboptimal design choices. To address this, an approach is presented that uses reciprocal holography to map the spatial TL performance of an inner dash. This method enables a more representative and targeted design process for achieving effective acoustic performance in fully built vehicle environments. Furthermore, the spatial Transmission Loss data can be combined with
Harry, Evan, Eandi, Giacomo
Influence of Common Mode Voltage Reduction Algorithms on High-Frequency Sideband Vibrations in PMSMs2026-01-0695To be published on 06/20/2026
Space Vector Pulse Width Modulation (SVPWM) induces Common Mode Voltage (CMV) in three-phase Voltage Source Inverters (VSIs). This CMV generates high-frequency sharp edges that can lead to significant leakage currents, which, in drive applications, may accelerate motor bearing degradation and cause winding insulation failure. To mitigate these issues, alternative modulation strategies such as Active-Zero State PWM (AZSPWM) and Near-State PWM (NSPWM) have been proposed in the literature. These techniques aim to reduce CMV and thereby decrease the degradation of electrical drives. This paper analyzes the Noise, Vibration, and Harshness (NVH) performance of AZSPWM and NSPWM compared with conventional SVPWM. The two CMV reduction schemes are tested on interior permanent magnet synchronous motors (IPMSMs) to evaluate their effectiveness in lowering CMV, as well as their impact on high-frequency sideband vibration harmonics. The results show that, although CMV is effectively reduced
Khamis, Mahmoud Aly, Tatar, Andrei Alexandru, Repecho, Victor, Doria-Cerezo, Arnau
NVH Aspects of DC Charging2026-01-0703To be published on 06/20/2026
The deployment of high-power DC charging infrastructure for electric vehicles introduces new challenges in managing noise, particularly in public environments where acoustic comfort and regulatory compliance are essential. Noise emissions from both charging stations and vehicles during charging are a concern for operators of charging parks regarding customer experience and sound immission regulations. AVL employed a structured three-step approach to develop a non-expert tool for assessing the noise radiation of charging stations and vehicles during the charging phase. In a first step, AVL characterized the noise emissions with sound power measurements. Secondly, the measurement results were transferred to the virtual domain. To achieve this, the vehicles and charging station were characterized in the simulation with multiple monopole sources supported by transfer function measurements. This simulation model was validated against the sound power measurement results. After successful
Gojo, Josef, Polanz, Markus, Graf, Bernhard, Langjahr, Paco, Mehrgou, Mehdi
High-Fidelity NVH Analysis Model Development Process for EV Traction Motors Based on Experimental Correlation2026-01-0685To be published on 06/20/2026
This study presents a high-fidelity NVH (Noise, Vibration, Harshness) analysis model development process for EV traction motors. The proposed process consists of two main components: Path refinement through structural stiffness tuning, and Source refinement, focused on the motor’s excitation mechanisms. Model accuracy was validated through comparison of simulation results with dyno test data, with particular focus on the 24th-order electromagnetic vibration observed in an 8-pole, 48-slot motor. Path refinement was achieved through modal correlation between experimental results and finite element (FE) analysis. Nine modal test and simulation stages were conducted, ranging from individual components to the complete motor assembly. Mode shapes were compared using the Modal Assurance Criterion (MAC), and natural frequencies were matched within a 5% error margin by adjusting FE material properties. For the 24th-order electromagnetic vibration, simulation results agreed with test data within
Kim, Donghee, Kim, Dong-Jun, Lee, SangHan, Kim, Seon Hyeong, Hwang, Seung Gyu, Valente, Giorgio, Parisouz, Shahriar, Halse, Christopher
Electric drive unit housing ribbing for low noise radiation2026-01-0687To be published on 06/20/2026
Although propulsion noise often constitutes a minority of the overall noise in electric vehicles, it remains an important quality indicator due to its high-frequency tonal character, which is undesirable even at low levels. There are many factors that influence the interior car levels of propulsion noise, i.e. gear whine and electric motor whine. The primary ones to consider are the electric drive units (EDU) internal forces, but also secondary properties such as EDU housing design and encapsulation, vehicle sound pack and mount isolation play important roles. This work focuses on EDU housing design and more particularly on the housing ribbing that enables attachment point stiffness and housing strength, but which can also cause problems in terms of noise radiation. Numerical parameter studies on geometrical properties such as length dimensions, thickness and curvature were performed on single ribs of different types. For each design iteration, the key performance indicators radiated
Lennström, David, Malm, Oskar, wurzinger, Jakob, Cederlund, Johan
A High-Performance Computing Strategy for Acoustic Encapsulation Modeling of Electric Vehicle Subsystems Using Coupled BEM–PEM–FEM Methods2026-01-0694To be published on 06/20/2026
Electric vehicle subsystems, including powertrains, electric motors, and gearboxes, pose new challenges in achieving stringent acoustic performance targets for both interior and exterior noise. These challenges are intensified by increasingly demanding customer expectations regarding interior acoustic comfort, which encompasses the reduction of intrusive noise sources and the enhancement of overall sound quality across a broad frequency spectrum. A primary concern associated with electric vehicles subsystems is the generation of high-frequency tonal noise, commonly referred to as whine noise, which can significantly impact acoustic performance and passenger comfort. High-frequency whine noise propagates through multiple transmission paths and can be effectively attenuated at the source through encapsulation strategies, which also contribute to broadband noise reduction across a wide frequency spectrum. To predict the acoustic performance of encapsulation, a coupled simulation approach
Amichi, Kamel, Calloni, Massimiliano
Analytical Magnetic Circuit Modeling and Parameter Estimation of a PMSM for Spatial Harmonics and Radial Forces Characterization2026-01-0677To be published on 06/20/2026
Electromagnetic excitations originating from air-gap flux distortions and radial forces are a dominant source of noise and vibration in Permanent Magnet Synchronous Motor (PMSM) operating at low-to-medium speeds. While finite-element analysis provides detailed insights into these effects, it is computationally intensive and often requires precise geometrical data. Conversely, conventional dq0-based models fail to represent slotting effects and nonsinusoidal fluxes, limiting their accuracy in harmonic prediction. This paper proposes an analytical model of a three-phase PMSM based on a Magnetic Equivalent Circuit (MEC) to accurately identify spatial harmonics and compute current-induced radial forces. An offline parameter estimation procedure is employed to characterize the magnetic circuit, making the model adaptable to various motor topologies and pole configurations without relying on detailed geometry. The proposed approach enables the derivation of the machine’s electrical and
Luciano, Ludovica, Doria-Cerezo, Arnau, Salamone, Nicolò
A Modeling and Experimental Study of the Argon Power Cycle Using Mixing-Controlled Combustion2026-01-5043To be published on 06/19/2026
The closed-cycle hydrogen-fueled argon power cycle is a zero emissions concept that combines a carbon-free fuel with argon as a diluent replacement for nitrogen. The lack of nitrogen in the argon power cycle results in zero NOx emissions on an internal combustion engine platform. There is also massive efficiency improvement because argon is monatomic and has a very high ratio of specific heats. However, this will also result in combustion temperatures and pressures exceeding those normally achieved on an air-standard engine platform. The literature shows conflict between modeling, which promises incredibly high efficiency gains, and experiment, which show more modest efficiency gains. This work combined thermodynamic modeling, literature analysis, and experiments to understand this discrepancy and ultimately understand what level of efficiency gain can be expected for the argon power cycle. It was found that while low compression ratio engines stand to see the largest relative
Gainey, Brian, Ahrling, Christoffer, Tunestal, Per, Tuner, Martin
Study of Hot Air Recirculation in Engine Compartment of a Newly Developed Sport Utility Vehicle03-19-03-00136/17/2026
During idling tests of a newly developed sport utility vehicle (SUV) under tropical high-temperature conditions, the condenser surface temperature exceeded the allowable range, degrading the air-conditioning system’s cooling performance. In this study, a three-dimensional computational fluid dynamics (CFD) model of the engine compartment flow field was established using STAR-CCM+. The results reveal that under idling conditions, the kinetic energy of hot air passing through the cooling module was insufficient to overcome the pressure difference between the front and rear sections, thus inducing hot air recirculation (HAR) and increasing the overall compartment temperature. To address the unfavorable flow field characteristics, four structural improvements were proposed and simulated for both flow and temperature fields. Through comparative analysis, the optimal scheme was determined: installing a flow guide baffle above the engine. Simulation results show that the airflow velocity
Shi, Huojie, Rao, R.H., Chen, J., Zheng, Z.L.
BOLT, MACHINE - DOUBLE HEXAGON EXTENDED WASHER HEAD, PD SHANK, CORROSION AND HEAT RESISTANT STEEL, UNS S41800, 140 KSI MIN, .1900-32 UNJF-3AAS9885C (Current)6/15/2026
E-25 General Standards for Aerospace and Propulsion Systems
BOLT, MACHINE - DOUBLE HEXAGON EXTENDED WASHER HEAD, CLOSE TOLERANCE SHANK, AMS4967 (UNS R56400), 160 KSI, .2500-28 UNJF-3AAS3148C (Current)6/15/2026
SCOPE IS UNAVAILABLE
E-25 General Standards for Aerospace and Propulsion Systems
BOLT, MACHINE - DOUBLE HEXAGON EXTENDED WASHER HEAD, CLOSE TOLERANCE SHANK, AMS4967 (UNS R56400), 160 KSI, .4375-20 UNJF-3AAS3151C (Current)6/15/2026
E-25 General Standards for Aerospace and Propulsion Systems
Hydraulic Filter Elements - Method for Evaluating Dynamic Efficiency with Cyclic FlowARP4205A (Current)6/15/2026
This SAE Aerospace Recommended Practice (ARP) describes a method for evaluating the performance of filter elements designed for aerospace hydraulic systems. The performance is measured and reported in terms of filtration ratios and stabilized contamination levels while testing with cyclic flow.
A-6C1 Fluids and Contamination Control Committee
BOLT, MACHINE - DOUBLE HEXAGON EXTENDED WASHER HEAD, CLOSE TOLERANCE SHANK, AMS4967 (UNS R56400), 1600 KSI, .3125-24 UNJF-3AAS3149C (Current)6/15/2026
E-25 General Standards for Aerospace and Propulsion Systems
NUT, SELF-LOCKING, EXTENDED DOUBLE HEXAGON, REDUCED FLANGE, DRY FILM LUBE, UNS S66286, CLASS: 160 KSI/800 °FAS3486E (Current)6/12/2026
E-25 General Standards for Aerospace and Propulsion Systems
BOLT, TEE HEAD - AMS5662, CHAMFERED, .3750-24 UNJF-3A (STRESS RUPTURE RESISTANT)AS3412C (Current)6/12/2026
E-25 General Standards for Aerospace and Propulsion Systems
NUT, SELF-LOCKING, PLATE, SIDE BY SIDE, REDUCED RIVET SPACING, LOW HEIGHT, UNS S66286, CLASS: 125 KSI/800 °FAS3482E (Current)6/12/2026
E-25 General Standards for Aerospace and Propulsion Systems
NUT, SELF-LOCKING, SHANK, UNS S66286 SILVER PLATE ON THREAD ONLY, UNJ THREADAS3534B (Current)6/12/2026
E-25 General Standards for Aerospace and Propulsion Systems
BOLT, TEE HEAD - AMS5662, CHAMFERED, .2500-28 UNJF-3A (STRESS RUPTURE RESISTANT)AS3410C (Current)6/12/2026
E-25 General Standards for Aerospace and Propulsion Systems
Gland Design Criteria and Dimensions for Dynamic Radial O-Ring Seal Applications Specifically for Engine and Engine Control Systems Operating at 1500 psi MaxARP1233B (Current)6/12/2026
This document recommends standard gland design criteria and dimensions for dynamic radial O-ring seal applications specifically for engine and engine control systems operating at pressures up to a maximum of 1500 psi (10342.14 kPa) and provides recommendations for modifying these glands in special applications. There are no provisions in this document for anti-extrusion devices. NOTE: The criteria set forth here are similar to but not identical with those in MIL-G-5514 and AS4716. This document is not intended to replace MIL-G-5514 or AS4716 for hydraulic applications.
A-6C2 Seals Committee
Accelerated Computational Fluid Dynamics (CFD)-Based Quantitative Prediction of Urea Deposition in Selective Catalytic Reduction (SCR) Systems2026-01-50416/12/2026
Mitigation of harmful emissions from oil-based engines is essential to avoid environmental pollution and comply with various NOx regulations across the globe. This can be partially achieved by injecting urea to produce ammonia (NH3), which reacts with NOx in a catalyst to produce harmless nitrogen (N2) and water vapor (H2O). However, urea deposition in a selective catalytic reduction (SCR) system poses a significant threat to the NOx removal process by not only reducing the urea conversion rate but also blocking the incoming flow and causing an additional pressure drop. Numerical modeling of this urea deposit formation involves multiphase flow physics coupled with accurate heat transfer calculations. Additionally, since urea decomposes into various by-products like biuret, cyanuric acid (CYA), and ammelide, detailed chemical kinetics modeling is equally important. Accurate and fast computational fluid dynamics (CFD) simulations can help accelerate SCR system design cycles, leading to a
Morab, Sumant R., Khalate, Suraj, Ansari, Shoaib, Yang, Pengze
NUT, SELF-LOCKING, PLATE, TWO LUG, LOW HEIGHT, UNS S66286, CLASS: 125 KSI/800 °FAS3478E (Current)6/12/2026
E-25 General Standards for Aerospace and Propulsion Systems
NUT, SELF-LOCKING, PLATE, ONE LUG, REDUCED RIVET SPACING, LOW HEIGHT, UNS S66286, CLASS: 125 KSI/800 °FAS3480E (Current)6/12/2026
E-25 General Standards for Aerospace and Propulsion Systems
NUT, SELF LOCKING, HEXAGON, REGULAR HEIGHT, UNS S66286, CLASS: 125 KSI/800 °FAS3483C (Current)6/12/2026
E-25 General Standards for Aerospace and Propulsion Systems
SAE Truck & Off-Highway Engineering: June 202626TOFHP066/11/2026
Hitting the road in the all-new VNR Volvo Trucks' revised VNR brings updated safety tech, improved fuel economy and driver comfort features to the regional haul segment. In fuel control How to ensure off-highway combustion systems operate with sufficient control to meet tightening emissions standards and evolving fuel landscapes without sacrificing reliability. Keeping industrial vehicles secure in a digital landscape OEMs, integrators and suppliers must continuously process, assess and identify platform vulnerabilities to prioritize and implement updates that protect systems from cyberattacks and data breaches. Editorial Diversification key for sustainable fleets ACT 2026: Uncertainty still exists over EPA 2027 NOx limit ZF bets big on hybrid transmissions Moog simplifies off-highway electrification Bosch shows off its first U.S. electrolyzer Microvision fast-tracks adoption of Luminar tech; eyes defense, industrial sectors Future-ready, customizable connectivity powers precision
Heavy-Duty Nonroad Material Handler Electrification Part 1: Real-World Drive Cycle Development02-19-03-00156/10/2026
Knowing a detailed operating cycle is critical for developing and testing equipment. Operating cycles can be separated by two clear distinctions: (1) regulatory or non-regulatory and (2) application at the engine-only or full machine level. The Environmental Protection Agency’s (EPA) Nonroad Transient Cycle (NRTC) may be a good representation of engine use in many types of equipment, but there is a gap in standardized and validated drive cycles specifically for nonroad material handlers. Lacking a standardized drive cycle makes it difficult to accurately benchmark machine performance and validate new powertrain technologies. The objective of this investigation is to illustrate the development of a custom drive cycle augmented with real-world customer use data that serves multiple purposes: (1) understand the range of operation and utilization that formulated inputs for electrified architecture analysis and (2) develop a repetitive and consistent maneuver to establish baseline energy
Czarnecki, Alexander, Goodenough, Bryant, Worm, Jeremy, Robinette, Darrell, LaTendresse, Phil, Westman, John
Unidirectional Carbon Fiber Tape Epoxy Repair Prepreg, Vacuum Curing Part 2 - Qualification Program for Fiber, Carbon Fiber Tape Prepreg, and Film AdhesiveAMS6885/2 (Current)6/10/2026
AMS6885/2 gives specific information about the qualification program for unidirectional carbon fiber tape epoxy repair prepreg capable of curing under vacuum for repair of carbon fiber reinforced epoxy structures. The prepreg system shall include an epoxy film adhesive to be applied in a co-bonding process with the prepreg for solid laminate and sandwich bonding.
AMS CACRC Commercial Aircraft Composite Repair Committee
STUD, LOCKED IN, KEY LOCKED, UNS S66286, 140 KSI/1200 °F LIGHTWEIGHT, SELF-BROACHING KEYSAS3543B (Current)6/10/2026
E-25 General Standards for Aerospace and Propulsion Systems
Items per page:
1 – 50 of 64328