Design and Development of Test Rigs for Experimental Investigation of Flow Loss and Heat Transfer in a Stirling Engine Heater Head

摘要

For the investigation of flow loss and heat transfer in a Stirling Engine Heater Head (HH), two benchtop test rigs were designed and manufactured. One rig is to evaluate flow loss in oscillating flow conditions (callcd flow loss test rig- FLTR) and another is to evaluate heat transfer in unidirectional flow conditions (called heat transfer test rig- HTTR). The main test section- heater head, is additively manufactured of Inconel 625 by i3D MFG; the test section also consists of an additively manufactured regenerator and a heat rejecter. For the FLTR, a linear actuator from Parker is used to generate and maintain the oscillating flow by driving a piston in oscillatory motion. The rod and the piston are sealed against the working fluid leakage using Trelleborg seals. At room temperature, by varying the charge pressure, frequency, and stroke length, multiple test conditions can be achieved for experimentation. For the HTTR, a Gast's high-flow, low-pressure compressed air blower is used to deliver the unidirectional flow. The data acquisition (DAQ) is comprised of National Instruments' cDAQ and modules to measure piston's motion in real time, dynamic pressure with Kistler's pressure transducers, and temperatures with OMEGA's thermocouples. Presented also are the testing procedures, preliminary results, expected results from Sage, and discussion of computational fluid dynamics (CFD) outputs that is used to check against the measured data from the test rigs.