A novel hybrid-energy heat pump with refrigerant injection: Performance characterization and injection optimization

摘要: Abstract Heat pumps have been widely used for space heating towards sustainable buildings. Thermally-driven absorption heat can greatly reduce electricity consumption but suffer from low reliability, applicability or efficiency under some circumstances. To address these problems, this study proposes a novel hybrid-energy pump (HEHP) with refrigerant injection, offering high flexibility to gradually transform an cycle compression cycle. The injection the required driving temperatures of sub-cycle, aiming utilize energy lower temperatures. Thermodynamic models established verified accuracy characterize capacity, COP (coefficient performance) and PEE (primary efficiency) various ratios (RAHP) pressure (CR). Results show that constant-frequency HEHP yields more stable capacities while variable-frequency COPs. increases significantly RAHP, reaching 17.19~42.34 RAHP 0.8 two HEHPs. As CR increases, capacity decreases, decreases better conditions (high Tgin Tein). After optimization, optimal is found increase as Tein maximum 1.4~2.5. PEEs are 0.99~1.62, 1.02~1.52, 1.04~1.48, 1.045~1.46 0.2, 0.4, 0.6, 0.8, respectively. turning which higher rises −10 °C 8 °C 100 °C 130 °C.