Finite Element Analysis and Correlation with Physical Test of Tractor Hood Bang Endurance Test 2024-26-0071

Tractors primarily serve agricultural functions but are also employed in various other applications such as loading, construction, and hauling. Tractors comprise several key assembly, including the engine, transmission, front hood assembly, and skid, among others. The hood is a critical assembly of the tractor, enclosing the engine and its associated parts. It is constructed from sheet metal with a 'Class A' surface finish for aesthetic purposes. The Hood is locked using latch mechanism mounted on the tractor chassis. The primary function of the hood is to facilitate the opening and closing of the hood assembly during servicing, and it often undergoes rough handling. Therefore, it becomes imperative to validate the durability of the hood assembly to ensure it can withstand the real-world conditions it encounters during these operations. One such test used to validate the hood assembly is the Hood Bang Test, which helps predict potential failures in the hood assembly due to the rigorous usage it experiences during repeated opening and closing.

This paper primarily concentrates on establishing the finite element (FE) methodology for simulating hood bang test and establishing a correlation between computer-aided engineering (CAE) simulations and physical tests. The FE model of the hood assembly was constructed using Hypermesh, and dynamic simulations, involving the latch mechanism, were executed with LS-DYNA, considering the actual impact velocity measurements. Subsequently, the model was used to predict the hood assembly durability based on the simulation results.

Correlation is a pivotal step in ensuring the reliability of CAE results. To achieve this, a hood bang test was conducted to measure acceleration (expressed in 'g' units) and strain. While the acceleration trends between CAE and the test closely aligned, there were still minor disparities. Following a thorough examination of the behavior and subsequent improvements to the FE model, a strong strain correlation was attained, and the acceleration trends were in close agreement.