Your Destination for Mobility Engineering Resources

In port construction, high-pile wharves—a primary structural form—are constantly exposed to marine environmental erosion, making corrosion a particularly prominent issue. Traditional anode installation typically relies on underwater diving operations, which suffer from low efficiency, high risks, and significant costs. To address these challenges, a novel installation technique requiring no divers has been developed. Through specialized equipment design and optimized construction processes, this technology enables remote, efficient, and safe anode installation. Research focuses on the design of non-diver anode support installation equipment, safety validation, and construction methodologies. Through theoretical analysis, numerical simulation, and field construction trials, this technology significantly enhances construction efficiency while reducing operational risks and costs. It provides a reliable solution for corrosion protection in high-pile wharves and holds significant importance for advancing port construction technology.
Lan, JinpingZhang, Shoulong
During fluid injection operations such as fracturing and well killing, the casing, cement sheath, and borehole wall rock are subjected to three-dimensional in-situ stresses and internal pressure. If the equivalent stress exceeds the material’s yield strength, component failure may occur, leading to wellbore failure or even blowout accidents. In order to investigate the stress distribution in wellbores under specific working conditions, a three-dimensional mechanical model of curved wellbores was established. By adopting the superposition principle and stress function method, the influence of horizontal in-situ stress non-uniformity on the fourth equivalent stress of various components was analyzed. The study demonstrates that under three-dimensional in-situ stress, the fourth equivalent stress of each component increases with the rise of horizontal in-situ stress load non-uniformity and azimuth angle. Meanwhile, borehole azimuth angle and in-situ stress load non-uniformity exert a greater influence on the fourth equivalent stress of the casing, while internal pressure has a lesser impact on it. The effects of azimuth angle, horizontal in-situ stress load non-uniformity, and internal pressure on the fourth equivalent stress of the casing are more significant than those on the cement sheath and borehole wall rock. The research results can provide theoretical and technical references for wellbore design and safety improvement, as well as for the structural safety assessment of components such as automotive chassis and body frames under complex dynamic loads.
Zhang, WenzheJiang, WuGuo, ZiwangCao, YinpingDou, Yihua
In order to reduce flow resistance loss in EV thermal management systems, this research builds a comprehensive computational process. The study used an advanced three-dimensional topology optimization technology integrating detailed fluid flow analysis with an adjoint sensitivity solver. This integrated computational approach helps systematic analysis of the complete design region. Thus, the internal flow channels with high resistance can be rearranged. The optimization target was set to minimize total pressure drop under defined operational parameters in real driving conditions. Through iterative calculation, the study successfully created three flow manifolds with different geometric shapes; each flow channel has its own distinct source of high resistance. The results show that the optimization effect is quite good, compared with the traditional manifold developed based on engineering experience; these optimized designs have reduced the pressure drop by 27%, 41%, and 74%, respectively. Beyond these quantitative pressure reduction data, detailed flow field analysis revealed that the optimized manifolds promote substantially improved hydrodynamic characteristics. The optimized internal channels generate more uniform velocity profiles, effectively diminish spatial velocity variations, and restrain vortex formation and recirculation zones. These useful flow field enhancements collectively contribute to a dramatic reduction in energy dissipation. This improves the thermodynamic efficiency of the thermal management system effectively. In order to conduct a more comprehensive verification, the optimized manifold was evaluated under various non-design operating conditions. These three designs consistently maintained stable performance characteristics and their low resistance properties in operating scenarios different from the original conditions, compared to the original manifold. Its stable performance under variable conditions shows the effectiveness of the topology-optimized methods and shows its broad operational adaptability. This is of great significance for the automotive application field, as the operating conditions in this field are often changing.
Liang, ZhixuanTian, RanYe, XiaokangWei, MingshanSun, XiaoxiaShen, Lili
This paper takes a seaplane as the research object, based on the roll damping commonly used in the field of ships, to carry out the applicability analysis and design technology research of the roll damping for the seaplane. A T-tail configuration was selected as the attachment. The design process involved sequentially selecting the horizontal stabilizer airfoil, designing the aspect ratio parameters, and determining the strut airfoil. Consequently, two T-tail design schemes with aspect ratios of 0.76 and 1.53 were proposed. Through the hydrodynamic performance analysis of the T-tail design installed on the seaplane, the advantages and disadvantages of the two T-tail designs in the wave environment are studied. The results demonstrate that the aspect ratio of the T-tail’s horizontal stabilizer directly affects the seaplane’s wave-induced motion response. The proposed design with a larger aspect ratio of 1.53 significantly reduces wave resistance and motion response across various conditions. In the case of a relatively small aspect ratio, the maximum pitching motion is reduced by 38.4%, and the maximum heave is reduced by 59%.
Jiang, TingPi, XufengHe, ChaoWen, ChangqingLi, Xu
The jet-trapped vortex combustor presented in this study was designed based on the trapped vortex combustor with good flame stability by introducing a jet flame-stabilization method. Leveraging the superior air-fuel mixing efficiency and enhanced heat and mass transfer of the jet stabilization method, this configuration addresses the inherent limitations of heat and mass transfer between the mainstream flow and the cavity in a conventional trapped vortex combustor. To investigate the influence of different hydrogen-air equivalence ratios on the flow dynamics, combustion performance, and emission within the jet-trapped vortex combustor, numerical simulations were conducted in this study. The results show that under different equivalence ratios, a vortex pair structure can be formed in the mixing zone between the hydrogen jet and the air jet. Complete combustion can be achieved at all equivalence ratios except for Φ = 1.56. When Φ is below 0.86, the axial distance required to achieve complete combustion progressively decreases as the equivalence ratio is reduced. The temperature distribution in the combustor is more uniform with minimal variation, and the concentration of NO emissions decreases progressively. Among these cases, the combustion efficiency, temperature distribution, and NO emission characteristic of the combustor are relatively better at Φ = 0.34.
Yan, PinghuaHou, XinglongRen, GuanlongSun, HaijunLuo, KunYang, Shucheng
For the solid-liquid mixing of hydroxy-terminated polybutadiene, which is a high-viscosity fluid with a viscosity of 3.5 Pa · s, and micron-sized silicon dioxide particles, this study employs the CFD-DEM numerical simulation method to analyze the solid-liquid mixing process of the ribbon-type composite impeller (RTC impeller). The stirring performance of the RTC impeller is investigated from perspectives including fluid flow field distribution and particle dispersion mechanism. The research results show that the main circulating flow generated by the RTC impeller generally exhibits a roughly symmetric distribution characteristic, and the flow pattern of the main circulating flow on both sides of the central structure is relatively balanced; however, there is a certain difference in the flow trend of the secondary circulating flow pattern on both sides of the central structure. The main circulating flow provides basic flow power for the secondary circulating flow, while the secondary circulating flow adjusts the local energy distribution through vortex motion. These two flows act synergistically to achieve an efficient solid-liquid mixing process.
Li, RuizhengZhang, YanSun, ZhenxingWu, Qiong
The comprehensive performance evaluation system for intelligent chassis vehicles comprises multi-level indicators and exhibits certain complexity. In this study, the Analytic Hierarchy Process (AHP) is employed to calculate the weights of indicators across different performance levels. Comprehensive performance is evaluated through the integration of objective indicator assessment and subjective scoring, and the evaluation results of the vehicle’s comprehensive performance are ultimately derived. This work provides a scientific scoring method for the product testing and evaluation of intelligent chassis vehicles.
Wu, ShiyuWang, JingxianGuo, RuilingLiang, DongLi, SaisaiYu, Xuetian
Advanced Driver Assistance Systems (ADAS) are increasingly integrated into heavy-duty commercial vehicles to improve road safety, mitigate accident severity, and enhance operational efficiency. In the context of braking systems, however, a significant gap remains between system calibration practices and real-world operating conditions, where most evaluations and validations of ADAS and braking performance are conducted under nominal or standardized load assumptions, which fail to represent the wide variability of payload magnitude and distribution typically observed in trucks, semi- trailers, and buses. Variations in vehicle mass and load distribution directly affect braking efficiency, axle load transfer, center of gravity (CG) position, and stability limits, posing critical challenges to both conventional brake systems and brake-related assistance functions. This paper presents an exploratory qualitative study based on a systematic literature review addressing the influence of variable loading on braking performance and the operation of ADAS in commercial vehicles. Scientific publications, experimental investigations, and technical reports from both academia and industry were thoroughly analyzed, with emphasis on service brake efficiency, load-dependent braking behavior, rollover propensity, and the performance of the ADAS systems. The reviewed studies demonstrate that longitudinal, lateral, and vertical CG displacements significantly modify braking force distribution, actuator effectiveness, and stopping distances, particularly under emergency braking and downhill driving conditions. Improper load distribution was consistently associated with reduced braking margins and increased instability risk. The findings further indicate that integrating load-aware strategies into braking control and ADAS calibration can improve braking consistency, reduce component stress, and enhance overall vehicle safety. As a contribution, this work emphasizes the need to incorporate variable load conditions into braking system evaluation, ADAS development, and certification procedures for heavy commercial vehicles, ensuring robust and reliable performance under real operating conditions.
Rubbo, Bruno TiagoDacol, Franco De BastianiDo Nascimento, Vagner
In conventional braking systems, the kinetic energy of a vehicle is predominantly converted into heat through friction, a thermodynamically inefficient process. This not only causes progressive wear of components but also leads to the release of various materials, including heavy metals and organic compounds. With increasing concern over non-exhaust emissions, the search for innovative solutions becomes imperative. In electrified vehicles (xEVs), regenerative braking emerges as a strategic technology, converting kinetic energy into electrical energy to recharge the battery and extend range. This process not only enhances the vehicle's energy efficiency but also results in reduced frequency and intensity of mechanical brake usage. Consequently, there is a direct reduction in the wear of friction braking components, which translates into a significant mitigation of particulate matter emissions associated with this wear. The optimization of these systems occurs through Cooperative Regenerative Braking (CRB), which intelligently integrates with hydraulic braking. The primary challenge lies in managing the transition between modes to recover maximum energy without compromising safety and driver comfort. This technical paper explores how CRB employs 'torque blending' via advanced ECUs and software to adjust in real-time the proportion of each braking type, aiming for maximum energy recovery in diverse driving scenarios. To verify the effectiveness of this system, practical tests were conducted on a vehicle. The results obtained from these tests were conclusive, demonstrating significant gains in energy efficiency, with an increased battery recharging capacity during decelerations, optimized by the braking system. This improvement in efficiency directly impacts the reduction in the use of the conventional friction brake system and, consequently, a sharp decrease in particulate matter emissions. In this context, the intelligent and cooperative management of regenerative braking is a strategic and fundamental component for building a more sustainable future in vehicular mobility.
Batagini, EmersonRomão, Bruno
With the goal of enhancing diesel engine adaptability to low-temperature environments and exploring cold-start potential at - 50 °C, this paper develops a one-dimensional simulation model for the cold-start system. The model is based on a method that utilizes a diesel heater to warm the coolant, which in turn heats the engine block and oil. The heating condition of coolant and oil of a 10-cylinder V-type engine within a specified time under a -50 °C environment is studied through simulation. We further optimized the cold-start process by enhancing the coolant flow distribution within each circulation circuit to improve overall thermal management and start-up efficiency. The results show that: at an ambient temperature of -50 °C, with a heating power of 80 kW, a total flow rate of 110 L/min, and an engine block flow rate of not less than 54 L/min, the diesel engine can raise the coolant temperature at the engine outlet to 40 °C and the oil temperature to -35 °C within 20 minutes. Through flow optimization, by maximizing the flow rate of the engine block heating circuit and reducing the flow diversion of the intercooler, the coolant temperature at the engine outlet can reach 40 °C in 18.9 minutes, while the oil is heated to -34.9 °C, and the final heating coolant temperature reaches 44.4 °C at 20 minutes. Compared to the situation without flow optimization, the time for the engine outlet coolant temperature to reach 40 °C was shortened by 0.55 minutes, and the final heating coolant temperature increased by 2.2 °C. Based on relevant experiments and the dynamic viscosity curve of 5 W engine oil, this paper holds that the starting conditions of a diesel engine can be met when the engine outlet coolant temperature reaches 40 °C, and the engine oil temperature reaches -35 °C.
Wang, JingfeiXie, PengWang, ZhuoXia, YingqiuZhang, XiaodongChen, KeWang, Guodong
To explore the structural strength of thin-walled joint structures in the combined power nozzle of high-speed vehicles under coupled thermal-acoustic-vibration multi-physics loading, this study conducted an analysis of vibration characteristics and a prediction of fatigue life. Focusing on a representative plate-beam bolted joint structural unit, the modeling, computation, and analysis of the structure’s vibration behaviors under thermal-acoustic-vibration loading were implemented by means of the coupled Finite Element Method/Boundary Element Method (Coupled FEM/BEM). The improved rainflow counting method was applied to quantify the time-domain vibration stress responses; a corresponding rainflow damage matrix was then established, and the structural fatigue life was predicted based on this framework.
Yu, HongfengSha, YundongLiu, ShuangYang, Yanze
PID
Lin, JingDeng, ZhixiangXu, JunWu, HuankunGuan, BinLiu, Lei
In this paper, the simulation software was used to conduct a thermal analysis of the design scheme of a certain type of forced air-cooled display and control console, and the results were compared with the experimental results. The results show that in an environment of 50 °C, the maximum temperature of the chip on this strong display control console does not exceed 98 °C, meeting the usage requirements of the chip and the thermal reliability requirements of the display control console. The thermal design scheme of the display and control console proposed in this paper has the advantages of a simple structural form, good heat dissipation effect, low fan noise, and consideration of the heat dissipation of multiple heat sources. It can provide a good reference for the thermal design of similar display and control consoles.
Li, Yun
This study aims to verify the accuracy and stability of a system used for measuring and analyzing the welding deformation of vehicle bodies under different welding parameters. A 3D laser scanner was employed to capture the surface topography data of the vehicle’s front deck before and after welding. In order to determine the welding deformation, PolyWorks software was utilized for deformation analysis, which processed the 3D scanning data and compared the post-welding data set. A dedicated vehicle body welding deformation measurement system was developed, including hardware configuration and software development. The BP neural network algorithm was adopted to predict the welding deformation, and the results indicated that the deviation between the predicted values and the average experimental measurements was less than 10%. This confirmed the practicality of the BP neural network in predicting welding deformation and highlighted its effectiveness in technical support for the optimization of welding parameters and deformation control in automotive manufacturing.
Li, LinaZhang, YiqiSun, HongchangWei, Xiezhen
In light of the significant roll/pitch experienced by traditional shipboard trestles due to wave action during the transfer of maintenance personnel from the operation and maintenance vessel to the offshore wind turbine base, an analysis of ship motion states was conducted under various sea conditions and ship manufacturing parameters. The kinematic capabilities and characteristics of the actuator were defined, and the mapping relationship between the wave compensation capability of the active wave compensation trestle and key design parameters, such as actuator power, was established. Consequently, an active wave compensation trestle executive mechanism was developed, incorporating lightweight research into its design. A prototype of the active wave compensation trestle was constructed and subjected to motion compensation testing. The results indicate that the prototype can effectively maintain stability between the ship and the offshore facility, thereby enhancing the safety of transferring personnel and improving maintenance efficiency.
Sun, TieruiZhao, PengfeiXin, RanQiu, JichengYang, XiaotaoShiyuan, E
2
Fu, ZhibinZhang, KaiYang, SiqiZhu, JiahaoQian, ZhiyuanJi, MingZhang, LeiWang, ZhiyiMa, Zhifei
The coupled multi-physical field environment in space, including vacuum, high-low temperature cycles, and temperature gradients, is the key factor affecting the life of the spacecraft’s rotary mechanism. Aiming at the use requirements of long-life space rotary mechanisms, this paper designs a multi-physical field accelerated life test scheme. This scheme simulates the vacuum environment, high-low temperature cycles, and temperature gradient conditions encountered during on-orbit operation. Ground-based accelerated life tests were conducted based on this scheme to verify the life of the mechanism under a comprehensive environment. Taking a certain type of space rotary mechanism as the test object, an integrated test platform was constructed, incorporating a vacuum simulation system, a temperature gradient control system, and a mechanism performance test system. Corresponding test procedures and failure criteria were established. Test results verified that after accumulating 130,000 ±7° small-angle reciprocating swings, the mechanism’s lifespan indicators met expectations. Post-test, the overall performance of the mechanism still satisfied the design requirements, with key moving components remaining in good condition. This study provides important experimental evidence for the on-orbit application of this mechanism type and offers valuable engineering reference for the design and evaluation of life tests for space mechanisms under multi-physical field coupling conditions.
Wang, HaomiaoDu, YuefeiHuang, MengzheYang, Jinping
Traditional methods for assessing bridge resilience often focus on single hazards or static conditions. Yet bridges today face more complex multi-hazard threats. To address this, this research develops a dynamic model to evaluate bridge resilience under multi-hazard conditions, which is intended to provide scientific support for decision-making to improve resilience. The study first establishes an index system that measures a bridge’s ability to absorb impacts, adapt during an event, and recover afterward. We also propose a method to calculate the coupling degree, which quantifies the amplification effect of multiple hazards, such as an earthquake followed by a flood, on each other’s impacts. Next, we clarify the interrelationships among key resilience factors. Using this understanding, we construct a system dynamics model that simulates the variation of bridge resilience over a full disaster cycle. Finally, a numerical simulation is carried out for a concrete continuous girder bridge in China’s coastal areas as a case study. The results confirm the model is valid and clearly show the differences in bridge resilience between single-hazard and multi-hazard events. More importantly, they prove that combined hazards make the bridge system much more vulnerable. The model also identifies the best strategies for intervention: a strategy that coordinates actions across all disaster phases performs best, as it most effectively reduces the impact of compound hazards and keeps the resilience curve smoother. In short, this study presents a new method for assessing bridge resilience and provides engineers and managers with a practical tool to identify structural weaknesses and optimize resource allocation for resilience improvement.
Lin, JiachenChai, Liang
In recent years, with the rapid increase in the market penetration of new energy vehicles, safety issues in electric vehicles, particularly those characterized by thermal runaway of power batteries, especially fire incidents caused by mechanical abuse from underbody impacts, have become a major focus of industry attention and social concern. This paper systematically compiles key data from electric vehicle underbody collision incidents, covering core parameters such as impact location, geometric features of obstacles (shape and size), and vehicle speed during accidents. Based on this data, the study further reviews existing underbody scraping evaluation protocols both domestically and internationally, with a focused comparison of the differences in mechanical load and battery pack response between two typical test methods: horizontal underbody scraping and 3° inclined underbody scraping. The findings of this research aim to provide data support for the refinement of relevant evaluation standards and to offer theoretical foundations and practical references for automotive manufacturers in optimizing the design and validation strategies for underbody protection of battery packs.
Wang, QingguiHe, QikeLi, WenboLi, ChunLi, Xiaodong
Crawler tractors are essential equipment for modern agricultural mechanization. Most existing mounted implement leveling systems rely on single-cylinder or dual-cylinder structures. These system can only make small-angle leveling and struggle under complex conditions such as large roll angles and asymmetric obstacle crossing. To address this, a modular auxiliary-frame leveling system (MALS) for agricultural implements is proposed. A 3D model of the leveling mechanism is designed, and a fuzzy adaptive PID control algorithm is implemented. The electric cylinder actuator is modeled via a transfer function linking input voltage to mechanical displacement, This provides a theoretical basis for controller design and dynamic performance evaluation. Subsequently, a crawler tractor asymmetric obstacle-crossing simulation model is constructed in Adams and integrated with Simulink to form a co-simulation platform, analyzing system performance under a 220 mm single-side obstacle condition. Simulation results indicate that the MALS achieves an extreme adjustment range of ±25°. Further validation on the integrated prototype confirms the effectiveness of the simulation model and control strategy. This demonstrated that the system can be adapted for use in complex terrain operations.
Lin, QiangLi, ChenyangChen, YuchenFeng, YangyuShao, GuifangZhu, Qingyuan
To solve the poor mobility of traditional camping vehicle chassis in complex terrains and confined spaces, this paper proposes an underactuated omnidirectional mobile chassis for outdoor camping vehicles. The chassis adopts a coupled commutation mechanism (double-crank elastic special-shaped connecting rods cross sliders), allowing each wheel to realize two motion modes (omnidirectional translation, in-situ rotation) with just one drive motor, reducing system complexity and cost. A control system based on the RoboMaster Development Board C Type integrates PID angle-loop control and motor speed-current dual closed-loop control for motion stability. Kinematic models for these two modes are established to derive the wheel parameter-chassis motion relationship. MATLAB R2023b-ADAMS 2024 co-simulations show the chassis maintains attitude stability under S-shaped curve, circular curve, and in-situ rotation; Qualisys 3D motion capture experiments confirm its stable attitude in omnidirectional movement.
Ren, YulongLu, ZhiguoYang, DongshengWu, DiZhang, TianyuQian, Zhenxin
Given the braking deviation of commercial vehicles, this paper discusses the influencing factors and uses Adams simulation software to accurately model the vehicle model due to the unreasonable match between the suspension system and the steering system. Through K&C analysis and dynamics analysis of the model, the root cause of braking deviation is identified, and the simulation method is used to quickly realize optimization and verification.
Yan, TangWang, JingxianSun, HongyangWu, Zhen
The driving cycle is the basic model of certification of vehicle fuel consumption and emissions, or calibration of powertrains. Standard regulatory driving cycles, such as WLTC, in general assume flat roads during their generation and fail to take into account the strong effect that road gradients have on vehicle operation and driving energy consumption. Such a shortcoming, then, leads to gross mismatches in adaptability when used for urban environments with typical hilly topography. To solve this problem, in this paper, we proposed a method for building driving cycles that consider the impact of slope with actual driving data. Initially, high-precision onboard data collectors were used to generate a total sum of 21, 350 km of driving data from the Munich area, thus creating a diversified driving data set with details such as vehicle speed, slope, and environmental information. Subsequently, joint probability distributions of “speed-acceleration” and “slope-slope change rate” are proposed by using the Micro-trip Method, and a novel chi-squared test algorithm is used to obtain a higher fidelity of urban driving cycle representative of typical conditions. Results of the driving cycle results show that the driving cycle built was close to the actual kinematics, indicating a deviation of less than 5%, and can capture the average uphill characteristic of 1.7%, which is quite well represented. Finally, in fact, validation of whole vehicle environmental chamber tests further demonstrates that the energy consumption prediction error of the developed driving cycle is just 2.2%, much lower than 19.1% error of WLTC. It highlights the importance of considering slope parameters in improving the accuracy of energy consumption calibration for an EV operating on complex slope terrains. Furthermore, it underscores that converting the real-world driving data into lab-based driving cycles can reduce the cost and time of actual road tests for Chinese companies going to the overseas markets, thereby offering support for the international marketing strategy of a global database.
Tian, LichenJiang, PingGao, WangLiang, YongkaiMa, KunqiYu, Hanzhengnan
As a key structural component of scroll compressors, the forming quality of the scroll plate directly affects overall performance. To address the issues of high forming load and poor rib filling in conventional processes, this study investigates the semisolid closed-die forging of 6061 aluminum alloy through numerical simulation. Semisolid rheological data were obtained from high-temperature compression tests. We also formulated an Arrhenius-type constitutive model to predict material behavior. This model proved highly reliable, achieving a correlation coefficient of 0.99547 and keeping the average absolute relative error down to 3.67%. By employing both orthogonal experiments and simulations, we evaluated how different process parameters impacted the outcome. This analysis ultimately yielded an optimal parameter combination: a die temperature of 350°C, a billet temperature of 600°C, and a punch velocity of 10mm/s. Under these conditions, the forming load, flow behavior, stress–strain distribution, and temperature evolution were analyzed. The results show complete rib filling, uniform deformation, and absence of defects, providing theoretical guidance for industrial applications of semisolid closed-die forging of scroll plates.
Xiong, LinhuaZhang, MengjiaoChang, MingLiu, BoyangWang, YongfeiZhao, Shengdun