Performance of a Miniature Reciprocating Expander for a Heat Actuated Heat Pump

摘要: A miniature reciprocating expander is being developed at Oregon State University as part of a larger program to develop heat actuated pump for portable applications. prototype unit has been demonstrated produce up 20 W shaft power 2500 rpm using 60 psig, room temperature nitrogen the input. Assuming adiabatic conditions, appears operate 80% isentropic efficiency. However, indications are presented that significant transfer occurring and resulting in lower polytropic These include warmer than expected exhaust temperatures expansion exponents below capacity ratio fluid. It anticipated losses will be greatly reduced by working fluid with much ratio. Nomenclature �s, �p = efficiency, respectively � rotational position (TDC 0) Cp constant pressure specific D cylinder diameter hi enthalpy inlet mass he