High-order control volume finite element method for thermal stress analysis of the piston with thermal barrier coating

Abstract:

To study the thermal stress of thermal barrier coating (TBC) piston, a new three-dimensional control volume finite volume method (CV-FEM) has been developed for thermal stress problem with composite material. The numerical discrete process of the governing equation is given in detail with 10-node high-order tetrahedral grid. Using the staggered grid technique, the unknown variables are defined at the cell vertex, while the physical parameters of material are defined at the cell center．The developed high-order CV-FEM was used to simulate the thermoelastic fields of annulus, the predicted results show good agreement with the ANSYS results. Then, the developed CV-FEM was used to simulate the thermoelastic field of the piston with laminated material and functional graded material (FGM). The results show that the maximum temperature is located in the boundary area between the combustion chamber and the top surface, and the maximum stress is around the cohesive layer, the maximum stress amplitude cannot be effectively reduced by changing the composition and distribution of the laminated TBC piston, or by changing the material gradient coefficient of FGM TBC piston, the maximum stress in the laminated and FGM pistons can be reduced effectively by introducing FGM which material properties gradually change from metal matrix to adhesive into the cohesive layer, the maximum stress can be decreased about 20%～30%, and the stress concentration problem can be improved significantly.