Numerical Simulation of Instantaneous Heat Transfer in Reciprocating Internal Combustion Engines

Abstract

This study provides a detailed instantaneous heat transfer solution in a cylinder during a motored cycle. The piston-cylinder assembly is modeled by a two-dimensional cavity with a sinusoidal moving wall. A high order differential algorithm is used to solve the unsteady compressible Navier-Stokes equations. The order of differencing is raised progressively from the walls toward the center of the cylinder, enabling oscillation free and accurate calculation on a very coarse grid. The numerical fluxes are integrated based on the dual-time stepping of the preconditioned matrix with a third-order Runge-Kutta scheme. The absolute pressure is determined by enforcing the global mass conservation for each grid. The predicted results of the absolute pressure, temperature, and velocity components of the fluid inside the cylinder at any instant during the start-up and the periodically stable periods are compared well with the results given in the literature.