Study On Crashworthiness Of Heavy Truck Cab On The Structural Optimization

With the rapid development of transportation, the number of cars continues to increase, more and more traffic accidents occur frequently, so people pay more attention to security issues. In recent years, as Chian'sincreasing requirements on the high-speed heavy-duty, the passive safety of heavy trucks is becoming increasingly prominent. As the safe and protecting device, the heavy-duty truck cab should have enough stiffness and strength. Because the limitation of the composition, the flat truck is restricted when front crash occurs, the metamorphosis of the heavy-truck are usually very large, so it hurts the people in the cab. At the moment, people have give rise to widespread concern about the safety of the heavy-duty truck. The countries in Europe pay attention to the safety of the heavy-duty earlier, the Economic Commission for Europe has promulgated the regulation《UNIFORM PROVISIONS CONCERNING THE APPROVAL OF VEHICLES WITH REGARD TO THE PROTECTION OF THE OCCUPANTS OF THE CAB OF A COMMERCIAL VEHICLE》(ECE R29).But there is little research on crash safety and no compulsory regulation has been published in our country.The vehicle crash experiment is the most accurate and reliable way in the vehicle safety research at the new vehicle developing process. The new developing vehicle's crashworthiness will be tested by real vehicle crash experiment. But this kind experiment will cause serious consequence to the vehicle ,and needs many times crash ,expensive and last long time .So to evaluate the vehicle's structural at the designing stage by the computer's emulation ,we can find the week link of the former design ,guide the whole designing and optimize process effectively. This way can decrease the number of crash experiment, save the cost, and shorten the experiment's period, so the computer simulation is becoming as a reliable tendency of the vehicle. This dissertation combines a domestic car company and the State Institute of Automotive Engineering heavy-duty truck cab 863 development projects, uses theoretical analysis and numerical simulation method , uses explicit nonlinear Analysis software LS-DYNA to simulate the structural optimization of heavy-duty truck cab before and after the collision of frontal impact and HIP cap, analysis's the comparative results before and after the test, and evaluates the crashworthiness of the heavy-duty truck cab before and after the test. In this dissertation, the main research work carried out following.(1) In this paper, references to a large number of Chinese and English literature, and after some investigation and research to the heavy-duty truck cab collision status of the safety, give brief introductions to the safety of heavy-duty trucks and vehicle crash simulation theory respectively.(2) Establish the finite element model to the driver's body-in-white of the standard heavy-duty trucks with the HyperWorks software, and at the same time, establish a finite element model of suspension and finite element model of frame. Finally establish simulation models of static pressure cap and positive impact pendulum respectively, reference test standards and regulations ECE R29. In the process of establish models, I accumulate a large number of valuable methods and experience, Give theoretical and practical guidance to the similar models'finite element modeling, and a reasonable model of vehicle cab has laid a good foundation for obtain the next accurate simulation results of crashworthiness.(3) Select LS-DYNA software to simulate the structural optimization before and after the cab model pendulum impact simulation test positive respectively, and give safety evaluation to the simulation results about the energy curve, vehicle deformation, the maximum displacement point's displacement, stress changes, and the survival horizontal direction of members, then analyze the test results before and after the structural optimization. The results show that the structural optimization and bob around the driver's test results are a good touch, security, high performance, and reached the aims of designing the lightweight and safety at the same time.(4) Take simulation tests of the cab roof hydrostatic before and after the structural optimization of heavy-duty trucks, and evaluate the heavy-duty truck cab's safety after the test about the energy curve, vehicle deformation, the maximum displacement point's displacement, stress changes, and the survival horizontal direction of members. The results show that after the structural optimization of the HIP cab roof test has a good touch, security, high performance, and reached the aims of designing the lightweight and safety at the same time.The results of this study show that, using the computer simulation methods to analysis the cab's crashworthiness performance in the new stage of development can analysis the lightweight design and passive safety design synchronous, so it can evaluate and improve the crashworthiness of the heavy-duty truck cab, realize lightweight products and ensure the crashworthiness performance of new products Timely evaluation and to improve the crashworthiness of the driver's performance effectively at the same time. This method can guide the design of programs to improve and shorten the development cycle of new models, reduce the development costs and enhance product competitiveness, and provide security authentication for lightweight design. These practical problems and research methods in this paper provide some references for future safety study of heavy-duty truck cab, with some reference values.