Yingshuai Liu

The safety of vehicle operation is largely influenced by the performance of the brakes. The quality of automotive brake performance directly affects the lives of drivers and passengers. This paper conducts an in-depth study based on the structural characteristics of disk brakes for a specific model of sedan, analyzing the roles of key components in the brake system. Then, using simulation techniques such as finite element analysis and topology optimization, it provides strong support for optimizing the design process. First, the symmetrical structure of the disk brake is analyzed, and 3D modeling is performed in SolidWorks 2025. Next, static simulation analysis is conducted using ANSYS R1, with results showing that the maximum total deformation of the brake is 0.038 mm (not strain), and the maximum stress is 155.78 MPa, which meets the requirements for emergency braking. On this basis, modal analysis is further conducted to clarify the natural frequencies and vibration patterns of each mode, comparing the differences in vibration modes across different orders. Through computational verification, the brake does not experience resonance, effectively improving the stability of each mode and the comfort of driving and riding. Finally, the variable-density method enabled 10.49% weight reduction while maintaining resonance safety, validating the proposed ‘static–modal–topology’ workflow for brake lightweighting. Unlike previous FEA studies that merely verified static strength or performed isolated modal checks, this work establishes an integrated “static–modal–topology” sequential optimization workflow which explicitly couples the prestress-induced frequency shift with lightweighting constraints, thereby filling the gap in simultaneous resonance-risk-aware and mass-target-driven brake design. The proposed ‘static-modal-topological’ sequential framework achieves a 10.49% weight reduction rate, representing a 26.4% improvement over the 8.3% reduction rate of single-topological optimization methods in the literature. Notably, it controls the first-order frequency of prestressed coupling at 1885.7 Hz (exceeding the engine’s 200 Hz upper limit) for the first time, resolving the core contradiction of ‘difficulty in balancing lightweighting and resonance risk’.

As the core component of new energy vehicles, the performance of the steering axle will directly affect the overall maneuverability, stability, and safety of vehicle driving. The structural performance indexes of the steering axle of the pure electric vehicle are analyzed by the finite element method, and a reasonable improvement plan is given according to its shortcomings. Firstly, the 3D model of the steering axle is established by SolidWorks (SOLIDWORKS 2023), and the details are simplified appropriately and then imported into the ANSYS (ANSYS2020R2 software) platform for static force analysis and modal analysis. Then, the stress distribution, deformation, and the first six orders of intrinsic frequency values of the steering axle are calculated and analyzed by using four working conditions, such as regular driving, emergency braking, lateral slip, and uneven road excitation, and it is concluded that the maximum stress of the original structure under each working condition is less than the requirement of the ultimate stress value. However, from the results, the maximum stress value is concentrated in the emergency braking condition and appears in the intermediate beam corner and the steering knuckle journal, which is also the most dangerous condition. In the modal analysis, it is concluded that the intrinsic frequency of this symmetry structure is much larger than the excitation frequency, and it can produce better dynamic effects under the working conditions, and the dynamic performance is better. Based on this, combined with the results of the static analysis of the proposed new increase in the thickness of the intermediate beam to improve the structural strength of the improvement measures, for this symmetry structure, through the re-simulation of the effect of the most critical conditions (emergency braking), the maximum deformation of the steering axle has been greatly reduced. In addition, the overall stiffness of the symmetry structure has been greatly improved, while the maximum stress is still less than the value of the permissible stress range, and the modal characteristics of the structure has not been affected. The finite element analysis software can effectively evaluate the performance and improve the optimization of the steering axle, which has certain theoretical significance and engineering reference value.

As a pivotal component of the single-gear reducer, the casing of the miniature car reducer not only safeguards the internal transmission system but also interfaces seamlessly with the external structure. Currently, the structural design of domestic single-stage reducers primarily leans on experience and standardized specifications. To guarantee the reliable and stable operation of the casing, a high safety factor is often incorporated, which inevitably results in increased weight and necessitates secure bolting connections. This study presents an innovative scheme to design the flange with the box and realize the lightweight nature of the box by finite element analysis to reduce the manufacturing cost. Based on the working state of maximum torque and maximum speed, this study obtains the stress distribution of each bearing seat under different working conditions and carries out static and dynamic analysis combined with other coupling constraints. The analysis results show that the structure has high stiffness and strength, which is suitable for lightweight design, and that the first ten spontaneous vibration frequencies are far away from the excitation frequency of the inner and outer boundary, avoiding the resonance phenomenon. Moreover, this study proposes a new structure design method, which effectively improves the stiffness of the structure. Through the calculation of volume ratio before and after three optimizations, the optimal volume ratio of 30% is selected, unnecessary materials around the bearing seat are removed, and the layout of ribs is determined. After structural optimization, the weight of the shell is reduced by 10.2%, and both the static and dynamic characteristics meet the design requirements.

To address the limitations in the cruising range and improve the overall efficiency of Pure Electric Vehicles (PEVs), this study focuses on the lightweight design of PEV drive axles. Aligning with the current trend toward lightweight and integrated development in electric vehicles, the research is based on the concept of an integrated electric drive axle housing. A three-dimensional model of the electric vehicle axle was developed using three-dimensional modeling software(3D modeling software), taking into account the working principles and load characteristics of the electric drive axle. Subsequently, Finite Element Analysis (FEA) was performed using finite element analysis software to evaluate the stiffness, strength, and modal characteristics of the integrated electric drive axle housing. The study analyzed stress distribution, deformation patterns, and natural frequency ranges under various operating conditions. Based on the FEA results, the axle housing structure was optimized by reducing the wall thickness and modifying the material of components subjected to lower stress levels, with the goal of minimizing mass. The optimal solution involved adjusting the housing thickness to achieve a more uniform and efficient thickness distribution, thereby meeting the lightweight design objectives. Simulation verification of the optimized axle structure confirmed that the weight reduction was achieved without compromising the required strength and stiffness. The findings demonstrate that, while ensuring safety, the optimized axle structure achieved a 12% reduction in weight. This study provides a feasible solution and a solid theoretical foundation for advancing the development of lightweight electric vehicles.

With the increasing environmental pollution and resource consumption caused by automobiles, a lightweight design of automobiles is the best solution at present. In this paper, the load-bearing frame of pure electric SUVs is taken as the research object. The finite element analysis method is used to analyze the strength, stiffness and modal performance of the load-bearing frame, and the material selection of the frame is optimized according to the analysis results to achieve a lightweight design. First, a three-dimensional model of the pure electric SUV frame is established using SolidWorks software 2019 and then imported into ANSYS 2024 R1 Workbench for meshing and material property definition. Then, through finite element static analysis, the various force conditions of the frame under three typical working conditions of full-load bending, full-load braking and full-load turning are simulated; the stress distribution and deformation of the frame under different working conditions are confirmed; and the strength and stiffness performance of the frame are evaluated. After the above analysis, a modal analysis of the frame is carried out, and the natural frequency and vibration mode of the frame are finally obtained. According to the analysis results, the material replacement method is selected to optimize the lightweight design of the frame. The results show that the weight of the frame is significantly reduced after material optimization, while still meeting the strength, stiffness and modal performance requirements. This article provides a certain reference value for the lightweight design of pure electric SUV frames in the future.

This study investigates the structural integrity and dynamic behavior of symmetry-optimized battery pack systems for new energy vehicles through advanced finite element analysis. It examines symmetry-optimized battery pack systems with mechanically stable and thermally adaptive potentials. Leveraging geometric symmetry principles, a high-fidelity three-dimensional (3D) model was constructed in SolidWorks 2023 and subjected to symmetry-constrained static analysis on ANSYS Workbench 2021 R1 platform. The structural performance was systematically evaluated under three critical asymmetric loading scenarios: emergency left/right turns and braking conditions, with particular attention to symmetric stress distribution patterns. The numerical results confirmed the initial design’s compliance with mechanical requirements while revealing symmetric deformation characteristics in dominant mode shapes. Building upon symmetry-enhanced topology configuration, a novel lightweight strategy was implemented by substituting Q235 steel with ZL104 aluminum alloy. While mechanical symmetry has been widely studied, thermal gradients in battery packs can induce asymmetric expansions. For example, uneven cooling may cause localized warping in aluminum alloy shells. This multiphysics effect must be integrated into symmetry constraints to ensure true stability. Symmetric material distribution optimization reduced the mass by 19% while maintaining structural stability, as validated through comparative static and modal analyses. Notably, the symmetric eigenfrequency arrangement in optimized modules effectively avoids common vehicle excitation bands (8–12 Hz/25–35 Hz), demonstrating significant resonance risk reduction through frequency redistribution. This research establishes a symmetry-driven design paradigm that systematically coordinates structural efficiency with dynamic reliability, providing critical insights for developing next-generation battery systems with balanced performance characteristics.

Presents corrections to the paper, (Corrections to “Green Traffic-Oriented Heavy-Duty Vehicle Emission Characteristics of China VI Based on Portable Emission Measurement Systems”).

In the actual use process, especially under the low exhaust temperature in urban conditions, the actual NOx emission of diesel engines using the Urea SCR technology is higher than expected, which seriously affects the application of Urea SCR technology in urban diesel vehicles. To solve the defects of low-temperature freezing, urea crystallization in the exhaust pipeline at low exhaust temperature, and insufficient activity of the Urea SCR system at low exhaust temperature in the actual application process of the Urea SCR technology, this paper uses the Portable Emission Measurement System (PEMS) vehicle test system to run the real-world. A SAIC Hongyan Dump truck that meets the China VI emission standard is tested and studied, and the real-world emission characteristics of the Solid SCR system and the Urea SCR system are compared and studied. Among other things, solid-state SCR systems use solid ammonium as a precursor to ammonia, a change that reduces clogging problems due to icing and hydrolysis evaporation crystals at low temperatures compared to conventional aqueous urea solutions. This results in more reliable system operation in cold environments. Solid-state SCR technology offers a more efficient and reliable solution for diesel exhaust treatment through its unique ammonia supply method, system optimization and environmental adaptability, helping to reduce environmental pollution from diesel vehicles. The test results show that: Under real-world operation conditions, the NOx conversion efficiency of the Urea SCR system and the Solid SCR system with the same injection strategy is increased by 0.5% and the NOx emission is reduced by 8.9% when the window average temperature is 228.8°C and 231.3°C. For the PN emission, no matter whether the Urea SCR system or the Solid SCR system is selected, the results have little influence. Based on the Solid SCR system, CO, HC, NO, NO_X, and other pollutant emission factors gradually decrease and tend to be relatively stable with the increase in vehicle speed. The Solid SCR technology is a promising NOx emission control technology for diesel engines.

The motor drive system is pivotal for vehicles, particularly in new energy applications. However, conventional hybrid systems, which combine generator sets and single batteries in parallel configurations, fail to meet the operational demands of large pure electric mining dump trucks under fluctuating power requirements—such as high reserve power during acceleration and robust energy recovery during braking. Traditional single-motor configurations struggle to balance low-speed, high-torque operations and high-speed driving within cost-effective ranges, often necessitating oversized motors or multi-gear transmissions. To address these challenges, this paper proposes a dual-motor symmetric powertrain configuration with a seven-speed gearbox, tailored to the extreme operating conditions of mining environments. By integrating a high-speed, low-torque motor and a low-speed, high-torque motor through dynamic power coupling, the system optimizes energy utilization while ensuring sufficient driving force. The simulation results under extreme conditions (e.g., 33% gradient climbs and heavy-load downhill braking) demonstrate that the proposed configuration achieves a peak torque of 267 kNm (200% improvement over single-motor systems) and a system efficiency of 92.4% (vs. 41.7% for diesel counterparts). Additionally, energy recovery efficiency reaches 85%, reducing energy consumption to 4.75 kWh/km (83% lower than diesel trucks) and life cycle costs by 38% (USD 5.34/km). Field tests in open-pit mines validate the reliability of the design, with less than a 1.5% deviation in simulated versus actual performance. The modular architecture supports scalability for 60–400-ton mining trucks, offering a replicable solution for zero-emission mining operations in high-altitude regions, such as Tibet’s lithium mines, and advancing global efforts toward carbon neutrality.

The development of new energy vehicles, particularly electric vehicles, is robust, with the power battery pack being a core component of the battery system, playing a vital role in the vehicle’s range and safety. This study takes the battery pack of an electric vehicle as a subject, employing advanced three-dimensional modeling technology to conduct static and dynamic analyses. Through weight reduction and structural optimization, an innovative power battery pack design scheme is proposed, aiming to achieve a more efficient and lighter electric vehicle power system. The main research tasks are as follows: Firstly, we designed the main load-bearing components of a certain electric vehicle’s power battery pack and established a three-dimensional (3D) model. Then, the model was simplified according to the actual stress conditions of the power battery pack of the electric vehicle and imported into finite element analysis (FEA) software. Next, based on the fundamental principles of the finite element method (FEM), we conducted static analyses under three conditions: bumpy road sharp left turn, bumpy road sharp right turn, and bumpy road emergency braking. The analysis results indicate that the strength of the battery pack meets the allowable requirements, suggesting that the lower housing design has significant redundancy, providing guidance for subsequent optimization. Finally, through modal analysis, we extracted the first six modes of the power battery box, with the first mode frequency being 33.69 Hz. This suggests that the battery pack may experience resonance during actual operation. Based on the static and modal analysis results, we proposed a structural optimization and lightweight design solution for a certain electric vehicle battery pack and compared it with the pre-optimization data.