Design, fabrication and CFD modeling of a Stirling engine microregenerator
Résumé
This paper reports the design, fabrication and CFD modeling of a microregenerator in order to be integrated in a multiphase piezoelectric smart membrane Stirling engine. The application aims to recover waste heat at low temperatures and to convert it into electricity via the piezoelectric element. The suggested geometry for the microregenerator is a microchannel integrated with staggered DRIE etched silicon micropillars, the whole is encapsulated between two glass wafers. The porosity ranges from 0.8 to 0.9. A 2D numerical study of the microregenerator thermofluidic performances was investigated. Three gases (air, helium and
hydrogen) were investigated. The gas flow is set to be incompressible and viscous under laminar unidirectional steady flow conditions for low Reynolds number (<10). According to the obtained results, helium has shown the highest pressure drop since it’s the most viscous gas. The pressure drop encountered with helium gas is more than twice the one registered with hydrogen. Nevertheless it was the fastest gas to heat up. Trade-off between heat transfer and pressure drop needs to be reached.