A benchmark analysis of subcooled heat transfer in a novel half-unit-cylinder-head for verifying in-vehicle engine evaporative cooling under dynamic conditions

Abstract

Evaporative cooling (EC) is a potentially attractive method of thermal management in highly downsized engines. As a benchmark for robust EC system development, a novel half-unit-cylinder-head has been designed to study the heat transfer achievable with evaporative cooling strategies under realistic hot metal conditions with an appropriate coolant flow field. Multi-phase computational fluid dynamics (CFD) and conjugate heat transfer (CHT) analysis are performed under subcooled flow boiling conditions to achieve both the design requirements for the hot-side surfaces and the specification of heating arrangements. Analysis is undertaken to ensure that thermal diffusion and flow conditions are representative of coolant flow in highly-boosted IC engines. The CFD model predictions show good correlation with available experimental data for both heat flux and metal temperatures in a typical downsized pressure-charged spark-ignition engine cylinder head.