Unsteady Fluid Dynamics Simulation of a Stirling Engine Heater Head

Abstract

This paper presents hot-wire anemometry data from an experiment that replicates important features of oscillatory flows in Stirling engines. These features include impinging and sink flows, large-scale separation zones, recirculation bubbles, unsteady shear layers and spatially varying transition and relaminarization zones. In addition to a characterization of oscillatory flow, this paper presents and compares results gathered in a unidirectional investigation to determine when, during the oscillation cycle, quasi-steady results can be applied to Stirling engine design. This paper is part of a program that focuses on characterization of fluid flow and heat transfer within Stirling engines. The unsteady velocity data presented herein serves to support the development of 3-D CFD models and verify the conditions under which 1-D systems models may be applied. The ultimate goal is that Stirling engine design codes can be used with a greater degree of confidence.