Scheme Design Analysis For Combined Heating System Based On Water Source Heat Pump And Gas Fired Boiler

As a renewable energy utilization system, water source heat pump system not only reduces environmental pollution but also reduces energy consumption. The water source heat pump heating system has been used in the practical engineering. However the energy efficiency of heat pump unit is very low during the coldest period in winter, which make to reduce the heating output and increase power consumption of the heat pump unit. In general, initial investment of the water source heat pump is much more than the traditional heating. So using combined heating system based on water source heat pump and gas fired boiler can capitalize on strengths both energy conservation and environmental protection of water source heat pump system and reduce initial investment and operation cost of the system.In this research, the water source heat pump heating system in combination with the gas fired boiler was studied. The water source heat pump system is primary pump heat pump system, low temperature heat source side of heat pump adopt direct system and unit directly connected with the low temperature heat source water. In order to improve energy efficiency, using cascade model with gas fired boiler. The purpose of the study of combined heating system is to improve the system efficiency and energy saving. In the article, through designing rational heating capacity sharing strategy and using rational operation adjustment method to achieve this purpose.Firstly, making models of energy consumption and economical of heating system, the main energy consumption of the system is energy consumption of the main equipment, include water source heat pump, gas fired boiler and water pump, respectively established the mathematical models of energy consumption of capital equipment. The economic analysis of system is analysis of the initial investment and operation cost of the system. The economic analysis is achieved, which need to combined with the design distribution proportion of the system heat source and operation adjustment. And establishing constraint adjustment of combined heating system.Secondly, analyzing design program and regulation mode of combination heating system, design program of heat source can be determined through the trial combined with system running. And, establishing the mathematical model of heating parameters of different adjustment modes in heat user side and low temperature heat source side, include the supply and return water temperature and hot water flow of heat user side, the outlet temperature and flow of water source heat pump evaporator side, the outlet temperature of water source heat pump condenser side when water source heat pump with gas fired boiler both running. And analyzing energy consumption and economy of system combined with energy consumption of equipment in different adjustment modes.Finally, making the detailed calculation combining with an engineering case, analyzing on the applicability of each adjustment mode under different heat source design. And drawing a conclusion that economy of combined heating system with proper the heating capacity sharing strategy is more rational than water source heat pump heating system with single heat source. And analyzing sensitivity of initial investment, energy prices and basic yield. At last, analyzing and comparing radiator heating system and radiant panel heating system. Through the analysis of the case, drawing a conclusion that the best load ratio of design of water source heat pump on the economy is 0.61. This design scheme is less 7.6% than gas fired boiler system on energy consumption and less 6.5% in annual cost. This design scheme is less 3.9% than water source heat pump heating system in annual cost.