Temperature transients on engine combustion chamber walls—I. Finite-difference formulation, validation and grid optimization

A finite-difference (FD) code is developed to solve the 1-D transient heat conduction problem through combustion chamber walls of internal combustion (IC) engines. The FD equations are derived for Cartesian, cylindrical and spherical coordinate systems from basic principles, i.e. heat balance and rate equations, and are capable of handling temperature-dependent material properties. In order to minimize the computational time, the wall is divided into layers of increasing thickness in geometric progression. The code developed is a useful tool for studying surface temperature swings on combustion chamber surfaces having different geometries, especially of significance in ceramic engines. It can also handle several different material layers together, thus making it possible to study thin-wall deposit effects on engine heat loss or surface thermocouple readings.