Thermal analysis of an anodic oxide coating diesel engine piston using 3-D finite element method

According to the phenomenon that the piston's reliability and durability have been significantly weakened due to its high temperature, hard anodizing is used to hinder the heat transfer from the combustion gas to the metal base of the piston. Thermal analyses are performed on pistons with different thicknesses of anodic oxide coatings. The effects of coatings on the thermal behaviors of the pistons are investigated. The numerical results are compared with each other. It has been shown that the maximum surface temperature of the coated pistons with anodic oxide coating which has low thermal conductivity are significantly improved. Also, considering the hard anodizing process, the 100 ~ 150μm thickness of the anodic oxide coating would meet the requirements of the piston's reliability.