Date of Award

Fall 2021

Publication Type


Degree Name



Mechanical, Automotive, and Materials Engineering

First Advisor

R. Barron

Second Advisor

R. Balachandar


Plastic components, Computational Fluid Dynamics, Fluid-structure interaction




Plastic components are widely used on the exterior body of automotive vehicles. When the vehicle is moving, these components experience deformation caused by air flow. Simultaneously, the deformation affects the flow of air around the vehicle. This research is focused on developing virtual simulation techniques for determining the vehicle air dam behaviour under aerodynamic loads. The main objective of this research is to develop a fluid-structure interaction (FSI) methodology for predicting deflection of the air dam.

Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) codes are coupled so that fluid pressure and air dam displacement parameters are exchanged. The FSI simulation implements a file-based two-way coupling procedure. Each time the CFD simulation is run, a file containing the pressure field on the surface of the air dam is exported to the FEA code. Then, FEA applies the pressure field as a distributed load on the air dam to compute the displacement. The deformed air dam shape is transferred back to the CFD solver and the previous air dam in the CFD simulation is replaced with the deformed one. The pressure field is computed with the deformed air dam and file exchange is continued until the air dam no longer deforms. Once the simulation has converged, the displacement is compared with the wind tunnel data to assess the accuracy of the FSI model.