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This paper combines fluid software STAR-CCM+ and finite element software ABAQUS to solve the temperature field of this Gasoline engine exhaust manifold based on loose coupling method. Through the simulation of car parking cooling - full load condition at full speed, we estimate thermal fatigue life of the exhaust manifold with the plastic strain increment as the evaluation parameters. It can guide the direction of optimal design of the exhaust manifold. Here we also revealed how the bolt force affects the manifold elastic and plastic behavior.

Glass lifter is a key part of automobile door system. Guide rail is the carrier of glass lifter, and it bears various load cases when glass lifer works. Mass, stiffness and natural frequencies are the factors that influence the performance of glass lifter. In order to design a lighter and reasonable glass lifter, topology optimization methods are studied in this paper. In a rope-wheel glass lifter, design domain is determined by the mechanical structure and working conditions. Firstly, the single target continuum structure topology optimization mathematic models of guide rail are built in this paper, and analysis of multi-stiffness topology optimization are carried out accordingly in which volume fraction is set as 0.4, 0.5 and 0.6. These models are based on SIMP (Solid Isotropic Material with Penalization) theory.

While the car ownership increasing all over the world, the unutilized thermal energy in automobile exhaust system is gradually being realized and valued by researchers around the world for better driving energy efficiency. For the unexpected urban traffic, the frequent start and stop processes as well as the acceleration and deceleration lead to the temperature fluctuation of the exhaust gas, which means the unstable hot-end temperature of the thermoelectric module generator (TEG). By arranging the heat conduction oil circulation at the hot end, the hot-end temperature’s fluctuation of the TEG can be effectively reduced, at the expense of larger system size and additional energy supply for the circulation. This research improves the TEG hot-end temperature stability by installing solid heat capacity material(SHCM) to the area between the outer wall of the exhaust pipe and the TEG, which has the merits of simple structure, none energy consumption and light weight.

The automobile exhaust energy can be recovered by the thermoelectric module generator(TEG). Owing to the complex urban traffic, the exhaust gas’s temperature fluctuations are resulted, which means the unstable hot-end temperature of the TEG. By installing solid heat capacity material(SHCM) to the area between the outer wall of the exhaust pipe and the TEG, it is possible to appropriately reduce the temperature fluctuation, but there is still a fluctuation of the TEG’s power output. Then by adding voltage filter circuit (VFC) after the TEG, the power output stability can be improved. This research uses SHCM and VFC to improve the stability of the exhaust gas generation. Firstly, the three-dimensional heat transfer model of the exhaust pipe thermoelectric power generation system is established. The heat capacity materials with low thermal resistance and high heat capacity were selected as the research object based on previous research.

Li-ion power battery is the core component of the electric vehicle power system, and the battery temperature will increase because of the electrochemical reaction of the Li-ion battery. The heat accumulates inside of the battery, which can degrade the working performance of the power battery and shorten the battery cycle life. At present, the wind cooling technology is relatively mature. However, it cannot achieve ideal heat dissipation effect under the working conditions of the high-power or high ambient temperature. In this research, the battery thermal management is carried out by the characteristics of the working fluid’s flowing phase change heat transfer. The phase change working fluid is R-1233zd(E) which is a kind of environmentally friendly liquid with nonconductive and nonflammable. It can achieve the purpose of controlling the battery’s temperature using the characteristics of isothermal heat absorption under different gas phase rate of phase change working fluid.

The main objective of platoon control is coordinated motion of autonomous vehicle platooning with small intervehicle spacing while maintaining the same speed and acceleration as the leading vehicle, which can save energy consumption and improve traffic throughput. The conventional platoon control methods are confronted with the problem of manual parameter tuning. In order to addres this isue, a novel bifold platoon control approach leveraging a deep reinforcement learning-based model is proposed, which enables the platoon adapt to the complex traffic environment, and guarantees the safety of platoon. The upper layer controller based on the TD3 tuned PID algorithm outputs the desired acceleration. This integration mitigates the inconvenience of frequent manual parameter tuning asociated with the conventional PID algorithm. The lower layer controller tracks the desired acceleration based on the inverse vehicle dynamics model and feedback control.

In order to predict the thermal fatigue life of the internal combustion engine exhaust manifold effectively, it was necessary to accurately obtain the unsteady heat transfer process between hot streams and exhaust manifold all the time. This paper began with the establishment of unsteady coupled heat transfer model by using serial coupling method of CFD and FEA numerical simulations, then the bidirectional thermal coupling analysis between fluid and structure was realized, as a result, the difficulty that the transient thermal boundary conditions were applied to the solid boundary was solved. What's more, the specific coupling mode, the physical quantities delivery method on the coupling interface and the surface mesh match were studied. On this basis, the differences between strong coupling method and portioned treatment for solving steady thermal stress numerical analysis were compared, and a more convenient and rapid method for solving static thermal stress was found.

As an auxiliary braking device of heavy-duty vehicle, eddy current retarder can reduce the brake failure due to the high temperature of the main brake. Nevertheless, the eddy current retarder will generate high temperature locally during the working process of it, leading to the decline of the brake power. The study on the heating characteristics of eddy current retarder is advantageous to the layout and parameter design of the liquid cooling channel of the retarder body and prolong the effective time of the auxiliary brake. In this research, a new kind of integrated eddy current retarder has been established. The thermal-magnetic coupling characteristics are studied and the laws of variation in torque output of auxiliary brake affected by the body temperature of retarder are analyzed. The boundary conditions are provided for the construction of the cooling channel. Firstly, the distribution of magnetic field and the characteristics of eddy current are simulated.

In order to ensure driving safety, heavy vehicles are often equipped with hydraulic retarder, which provides sustained, stable braking torque and converts the vehicle kinetic energy into heat taken away by the cooling system when traveling on a long downhill. The conventional hydraulic retarder braking torque is modulated by adjusting the liquid filling rate, which leads to slow response and difficult control. In this paper, a new kind of magnetorheological (MR) fluid hydraulic retarder is designed by replacing the traditional transmission oil with MR fluid and arranging the excitation coils outside the working chamber. The braking torque can be controlled by the fluid viscosity of MR fluid with the variation of magnetic field. Compared with the traditional hydraulic retarder, the system has the advantages of fast response, easy control and high adjustment sensitivity.

The cabin air temperature increases quickly and can reach 80°C when the vehicle parks in the summer sunlight which has the bad influence on the occupants entering comfort. Some luxury vehicles, like Audi A8[1], reduce the internal temperature through operating air-condition in advance or using on-board battery to drive the cabin ventilator, which requires relatively complex control system and limits the system's operating time because of energy consumption. This research adopts the solar wing as the ventilation power supply and accomplishes the cabin real-time heat rejection by achieving the steady air circulation for both inside and outside environment. First, the static thermal transfer model of the crew cabin is established. Then, on the basis of the parameters of the prototype ventilation pipe, the ventilation model for the outside circulation is built.

The performance of an organic Rankine cycle (ORC) that recovers heat from the exhaust of a heavy-duty diesel engine was simulated. The work was an extension of a prior study that simulated the performance of an experimental ORC system developed and tested at Oak Ridge National laboratory (ORNL). The experimental data were used to set model parameters and validate the results of that simulation. For the current study the model was adapted to consider a 15 liter turbocharged engine versus the original 1.9 liter light-duty automotive turbodiesel studied by ORNL. Exhaust flow rate and temperature data for the heavy-duty engine were obtained from Southwest Research Institute (SwRI) for a range of steady-state engine speeds and loads without EGR. Because of the considerably higher exhaust gas flow rates of the heavy-duty engine, relative to the engine tested by ORNL, a different heat exchanger type was considered in order to keep exhaust pressure drop within practical bounds.

To prevent braking recession, heavy commercial vehicles are often equipped with fluid auxiliary braking devices, such as hydraulic retarder. Hydraulic retarder can convert the vehicle’s kinetic energy to the fluid heat energy, which can enormously alleviate the main brake’s workload. The traditional hydraulic retarder can provide enough braking torque but has a delay during the braking. In this paper, a new type of magnetorheological fluid (MR fluid) hydraulic retarder is introduced by replacing the traditional fluid with magnetorheological fluid because of its linear braking torque and quick response. By changing the magnetic field intensity, it is easier to control the braking torque than the traditional hydraulic retarder. The rise of magnetorheological fluid temperature during the braking period will reduce the hydraulic retarder’s performance.

The thermal management system is essential for the safe and long-term operation of the power battery. The temperature difference between the individual cells exceeds the acceleration of the battery performance, which leads to battery out of use and affects the performance of the vehicle. Compared with the low heat transfer coefficient of the air-cooling system, the complex structure of the liquid-cooling system and the large quality of phase change material system, the heat pipe has high thermal conductivity, strong isothermal performance and light weight, it’s an efficient cooling element that can be used for thermal management. In this study, the flat plate heat pipe(FPHP) is used to manage the temperature of the battery, through experiments, the optimized placement of the flat heat pipe is obtained.

Autonomous vehicles require the collaborative operation of multiple modules during their journey, and enhancing tracking performance is a key focus in the field of planning and control. To address this challenge, we propose a cooperative control strategy, which is designed based on the integration of model predictive control (MPC) and a dual proportional–integral–derivative approach, referred to as collaborative control of MPC and double PID (CMDP for short in this article).The CMDP controller accomplishes the execution of actions based on information from perception and planning modules. For lateral control, the MPC algorithm is employed, transforming the MPC’s optimal problem into a standard quadratic programming problem. Simultaneously, a fuzzy control is designed to achieve adaptive changes in the constraint values for steering angles.

In order to avoid the braking recession on heavy commercial vehicles caused by the long-distance continuous braking of the main brake, the hydraulic retarder is widely used as an important brake auxiliary device in various heavy commercial vehicles to improve the vehicle safety. However, the hydraulic retarder not only has the advantages of large braking torque and good stability, but also has the disadvantages of poor retarding ability at low rotating speed, braking lag and difficulty in accurately controlling the braking torque. This paper introduces a new type of hydraulic retarder. The new retarder replaces the oil in the retarder with magnetorheological fluid and applies a magnetic field in the retarder arrangement space, so that slows down the vehicle by using the rheological properties of the magnetorheological fluid under the magnetic field.

For cooperative adaptive cruise control (CACC) system, a robust following control algorithm based on fuzzy PID principle is adopted in this paper. Firstly, a nonlinear vehicle dynamics model considering the lag of driving force and acceleration constraints was established. Then, with the vehicle’s control hierarchic, the upper controller takes the relative speed between vehicles and the spacing error as inputs to output the following vehicle's target acceleration, while the lower controller takes the target acceleration as inputs and the throttle opening and brake master cylinder pressure as outputs. For the setting of target spacing, this paper additionally considers the relative speed between vehicles and the acceleration of the front vehicle. Through testing, compared with the traditional variable safety distance model, the average distance reduces by 5.43% when leading vehicle is accelerating, while increases by 2.74% in deceleration.

With the increasingly serious global environmental and energy problems, as well as the increasing number of vehicles, pure electric vehicles with its advantages of environmental protection, low noise and renewable energy, become an effective way to alleviate environmental pollution and energy crisis. Due to the current pure electric vehicle power battery technology is not perfect, the range of pure electric vehicle has a great limit. Through the braking energy recovery, the energy can be reused, the energy utilization rate can be improved, and the battery life of pure electric vehicles can be improved. In this paper, a pure electric vehicle is taken as the analysis object, and the whole vehicle analysis model is built. Through the comparative analysis, based on the driver's braking intention and vehicle running state, the braking energy recovery control strategy of double fuzzy control is proposed.

Focusing the vehicle riding safety and global environmental problems, plenty of solutions on vehicle braking systems appeals during the recent period. Criteria and standards set up for commercial vehicles which should have equipped assisted braking systems were established by amounts of governments. Since eddy current retarders plays an important role in the area of assisted braking system, this article presents an energy-recuperation retarder, which is parallel connected with the driveline through a planet gear system. This paper offers a particular Energy-Recuperation Eddy Current Retarder (ERECR) system with a pedal control system and its characteristics is presented, either. Initially, the constitution of the energy-recuperation eddy current retarder system is established whereas the working principle of the energy-recuperation eddy current retarder is presented by modeling the system and simulation.

In recent years, research on car-like robots has received more attention due to the rapid development of artificial intelligence from diverse disciplines. As essential parts, path planning and lateral path tracking control are the basis for car-like robots to complete automation tasks. Based on the two-degree-of-freedom vehicle dynamic model, this study profoundly analyzes the car-like robots’ path planning and lateral path tracking control. Three objectives: path length, path smoothness, and path safety, are defined and used to construct a multi-objective path planning model. By introducing an adaptive factor, redefining the selection of reference points, and using the cubic spline interpolation for path determination, an improved NGSA-III is proposed, which is mostly adapted in solving the multi-objective path planning problem.

In the Formula Student Electric China (FSEC), the body structure is generally divided into two types, truss steel tube body and carbon fiber load-bearing body (monocoque). The monocoque is loved by Formula Student teams around the world because it has a higher stiffness and lighter weight than the truss steel tube body. With the widespread application of monocoque, it also brings more problems. Due to the use of the monocoque, the connection between each component and the body was changed from the welding of the original truss steel pipe frame to a bolted connection. However, the bolted connection will provide a large preload force to the monocoque, resulting in the monocoque easily crushed in the local, so it is necessary to pre-bury an enhanced part in the monocoque to ensure the connection strength, that is, the embedded part. At present, aluminum plug-ins after topological hollow processing are being used.