Novel experimental research on the compression process in organic Rankine cycle (ORC)

摘要: Abstract Organic Rankine cycle (ORC) is one of the most promising methods for converting medium-low temperature thermal energy into power. Many studies have been performed to optimize operating conditions, select proper working fluids, design efficient expansion machines, etc. However, as major power-consuming component in ORC system, circulating pump rarely studied. Most theoretical only assume a constant value isentropic efficiency compression process, but this varies with different studies. A small-scale system built present work test performance diaphragm pump, and fluids R245fa, R123, R152a R600a are tested under various conditions. The efficiencies compressing those between 57.22% 93.51%. results show that volume flow rate pressure difference great influence on efficiency, increases difference. Under condition same difference, conforms order η R245fa  >  R123 . analyses about variation trend made from perspectives physical properties fluid driving mode which prove hitting velocity liquid main cause irreversible enthalpy increment. novel parameter α V / ρc p proposed identify pump. experimental decreases increment fluids.