Thermal analysis of a combustion chamber surrounded by deposits in an HCCI engine

In this study, temperature distribution in a CCD coated piston used in an HCCI engine was investigated and was guided by existing experimental results. A model based on experimental observations obtained from the experiments at Shell research center was developed by using finite element technique to investigate 3D thermal analyses for both clean and deposited piston. Effect of the CCD thickness on the temperature distribution was analyzed by comparing the results from the clean piston and deposited one. It was observed that the deposited surface temperature increases with increasing the thickness in a decreasing rate. Both aluminum and steel piston compared with each other in respect to the maximum temperature for the same CCD thicknesses, which were tn = 9 and tm = 30 in micro meters. Compared to the clean piston, maximum temperature on the top surface of the aluminum and steel metals diminish 6 °C and 9 °C respectively, because of CCD's relatively low heat transfer coefficient.

► Temperature distribution on the deposit CCD is a function of coating thickness.
► Maximum temperature on the surface of CCD coating is higher compared to clean piston.
► CCD thickness increases, maximum temperature increase at decreasing rate.
► On the top surface of the substrate, maximum temperature diminishes because of CCD.