An Analysis of Heat Transfer Effects on Surge Characteristics in Turbo Heat Pumps

This paper presents a new analysis of the effects of ambient temperature variations on the surge characteristics of turbo heat pumps. To this end, an analytical model capable of predicting unsteady behavior of surge in turbo heat pumps has been developed. In compression systems, surge is mostly caused by the compressor work exceeding the mechanical inertia of the system. In refrigeration systems, heat transfer in the condenser and evaporator can influence surge characteristics. The predictions demonstrate that the new model can accurately predict the limit cycle of behavior of turbo heat pumps after the surge onset. Also, predictions show that surge can be stabilized or removed by sufficient increase in the cooling water inlet temperature ,0 cw T .