Optimization Design And Verification For BIW Lightweight

Entering the twenty-first century with the vigorous development of automobile industry and the pressure of the energy and environmental crisis, the automobile industry energy saving and environmental protection technology has become the trend of the world automobile industry technology development. Accordingly for the target of energy saving and environmental protection, we need to use the modern lightweight technology or method to optimize the design in the vehicle development to reduce the weight and fuel consumption under the premise of ensuring vehicle comprehensive performance and quality.BIW is the carrier of whole vehicle and support the majority of parts. The weight of BIW is 2/5 of whole vehicle, so the lightweight optimization design of BIW is a very important step of the lightweight design of the vehicle.Based on the background of vehicle lightweight research of Dalian University of Technology automotive engineering, combining with my engineering experience of new vehicle development in the Automobile Technology Research Institute, this paper analyzes the structure and key performance indicators of BIW, and investigates the current evaluation method of BIW lightweight. By means of finite element analysis technology, this paper establishes a parametric model of BIW by using Altair Hypermesh software, and then carries out the key performance analysis of BIW by using MSC. Nastran software.Considering the redundancy design of BIW structure, this paper establishes finite element model of BIW and carries out the relative sensitivity analysis about part plate thickness and BIW key performance. Then the relationship between part thickness and key performance of BIW about weight, stiffness and mode is output and comprehensively analyzed. In this paper, based on the analysis results, 39 parts used for light weight optimization design about thickness, section, area and so on are selected. The key performance analysis of BIW stiffness and mode is carried out again for the optimized parts, and finally qualified by the test. The weight of BIW of some car is reduced from 388.5kg to 368.9kg by means of lightweight-oriented optimization design and verification. The key performance of BIW also meets the design targets, and the BIW reduce weight 19.6kg.