Design and Analysis of Automobile Hood

Abstract

Bonnet is a main component of front portion of a car one which is used for many purposes. It is used
to decorate the car and add luxurious look. Bonnet is made in aerodynamic shape to reduce air
resistance. Bonnet generally used to cover car engine. Therefore, the bonnet system is an access
panel to the engine compartment to enable maintenance of power train, drive belts, battery, fluid
levels and lamp units, and it gives minimum hindrance to aerodynamic flow. Car bonnets consist of
the upper panel and inner stiffener panel. For designing the hood 3D model CATIA V5R19 is used,
then this CATIA model imported in Ansys software for analysis. The generated finite element model
contains all components of the hood, but most important are the outer panel and the inner stiffener
panel, which are designed both in HSLA steel and aluminum alloy. The static load cases are defined
to analyze the structural stiffness of the different hood versions. The reinforcement member placed
between upper panel and inner stiffener panel to increase the strength of said panel. It is
fundamentally a reinforced skin panel with many safety and quality requirements. The reinforcements
consist of a structure made up of a base Material of plastic or aluminum and an insert material of
hard metal. The scope of the present investigation is to create the model of the conventional
components, further they are meshed, and boundary conditions are applied for different conditions.
Finally, the meshed models are analyzed to find the natural frequencies for different modes. Both
components with different material that is HSLA and Aluminum alloy are subjected to natural
frequency and harmonic analysis to get the conclusions regarding the NVH characteristics.