Width Adjustable Variable To Gap Hedge Frame Type Spray Car Frame Finite Element Analysis And Structure Optimization

Frame is a key assembly of the vehicle, and many other assemblies also take it as their carrier. Moreover, it endures complicated loads while traveling, so the strength and stiffness are critical during design phase. This paper takes prototype of Width Adjustable and Ground-clearance Variable Espalier Type Spraying Vehicle as target, which is the first sample of an863national project and still under R&D stage. Through thorough study of its structure, this paper adopts CATIA to get geometric model. Later, it is imported to ANSYS via general interface between softwares. Meanwhile, the FEM model is set up according to actual conditions and relevant documents.After simplification of loads and confirmation of boundary constraints, this paper respectively discusses stress and deformation of the model when it travels under four typical conditions, which are the horizontal bending, ultimate torsion, emergency braking and emergency turning. This paper also takes modal analysis, and has got the first twentieth vibration mode and inherent frequency. Fully guarantee the strength and stiffness from overall view, and check its reliability and durability.During experiment section this paper selects key sites to arrange strain gauges and imitates horizontal bending and ultimate torsion condition, accomplishing electric experiments based on frame experiment industry norms, then evaluating mechanical property and examining FEM model accuracy and reliability of numerical calculation. According to the comparison of ANSYS analysis and electric experiments data it could be inferred that the overall stress is less than ultimate tensile strength of material and could meet design requirements. But from certain point the strength has much surplus capacity, so its economy needs urgent improvement, providing important theoretical and practical reference for frame optimization design.In chapter of structure optimization, this paper conducts optimization design of the frame in accordance with previous research that aim to achieve lightweight result. According to established solution it takes gross mass as target that within tolerance range of strength and stiffness, optimizing dimensions of vertical and horizontal beams, then the thickness, improving the mechanical property and reducing its weight, saving raw materials and lowering cost. Moreover, the second sample vehicle has been manufactured in line with optimization result and taken field and road test. At last, it has got the survey report from state authority. Surely it achieves good performance. The test data demonstrates that the optimization solutions could well meet lightweight requirements, and increase product economy and competency.In a word, this paper creatively applies CAD/CAE technology to special purpose vehicle frame design. Through combination of electric experiment and FEM check static and modal performance of width adjustable and ground-clearance variable espalier type spraying vehicle, then directly applies the findings to frame structure optimization, and guides manufacture of the second sample vehicle. As a critical part of the863national project, this paper has great engineering significance.