Performance Research Of Industrial Cascade High Temperature Heat Pump

In the field of industrial applications,the demand for heating temperature is higher than that of civilian use.So the traditional civil Heat Pump can not meet the needs of the industrial field.The performance of industrial High Temperature Heat Pump is studied in this paper.High Temperature Heat Pump’s research consists of 2 issues.The first issue is to develop a good environmental protection,appropriate thermal cycle performance,compatible ability with higher temperature Heat pump.The other issue is to develop a key equipment of energy quality deployment,achieve High Temperature Heat Pump system optimization integration,and ultimately realize the deepening use of low-grade heat source.In order to find a suitable high temperature heat pump working fluid,we developed BY-6 which is a new type of high temperature non-azeotropic working fluid.The theoretical calculations show BY-6 always has optimal performance in six design conditions compared with the HFC245 ca,HFC245fa,HCFC123,when the evaporation temperature changes from 90°C to 115°C,with the condensing temperature vary from 145°C to 170°C.When the hot water of using side(high temperature cooling water)reaches 170°C,the condensing pressure is 2.53 MPa.Because of the urgent requirements of high temperature heat pump technology,BY-6 will be used widely.A cascade high temperature heat pump test rig is built.BY-6 and BY-3B are used as high and low working fluids respectively.The heat is absorbed at 50 °C,and the outlet water temperature of condenser(hot water temperature of use side)reaches 170°C.At this point,the condensing pressure of the high stage is 2.87 MPa,and the intermediate heat transfer temperature and pressure are moderate.The compression ratios at high and low stages are about 3.47 and 4.73 respectively.The COP at high and low stages are about 5.2 and 4.4 respectively.The COP of whole system is 2.39.The experiment shows that BY-6 has excellent performance.In addition,it reveals how the Heat Pump’s COP,Compressor power consumption and heating capacity vary with the outlet water temperature of condenser.This experiment provides the data support for the industrial application of High Temperature Heat Pump and sets up the theoretical foundation.The core component of industrial Heat Pump device is Compressor.In order to realize the industrial utilization of this research,this paper discusses the method of testing the performance of the compressor.Because former testing method for Compressor performance occupys large area,high investment and operation cost,a new testing method and device were proposed in this paper.According to the core component of the new testing method,a new thermodynamic numerical calculation design method for the geometric size of Ejectors is presented.The geometric size is obtained simultaneously with thermodynamic calculation.The design process fully reflects the idea of fluid structure coupling.