The Structure Design And Analysis Of Monocoque Hybrid City Bus Body

Automobile manufacturers around the world are now applying many advanced design and analysis measures for their new energy and energy saving vehicles development. At present, the hybrid electric bus has got rapid development with its own advantages in all kinds of new energy vehicles, and has been used mainly in city public transportation system.In this paper, according to the monocoque bus body structure characteristics, the load characteristics and the differences between hybrid bus and fuel bus, the geometric model of a monocoque hybrid city bus body is established. By simplifying reasonably the body frame geometry model, selecting finite element unit and body material, the finite element model (FEM) of the monocoque hybrid city bus is built by means of ANSYS software.According to "Regulations of Cars Drive Product Reliability Experiment", the vehicle prototype must be driven a certain mileage at a certain speed, respectively on high-speed road, general road and corner. The analysis of working conditions include: bending condition, emergent braking condition, emergent turning condition and limited torsion condition. Based on these four conditions, through the reasonable definition of load and constraint conditions, the static finite element analysis of the body frame is carried out, the strength and stiffness of body performance are evaluated. According to the requirements of the bus dynamic performance, the modal analysis of body frame is carried out. The lower order modal frequencies and mode shapes of body frame are obtained, and then the dynamic performance of the body frame is evaluated. The static and dynamic analysis results of hybrid city bus body can meet the requirements of safety performance, and there is a great potentiality for bus body frame improvement.Finally, with ensuring the requirement of safety performance, the body frame is improved for lightweight, at the same time to reduce bus emissions and decrease environment pollutants. Through a preliminary structural improvement, the body frame quality reduces296kg, which can provide some theory basis for further optimization design of the hybrid bus body.