Application Research Of Condensing Heat Of Water Source Heat Pump System

As a renewable energy technology, water source heat pump is energy conservation and environmental protection. Besides shortage problem, low energy utilization is also current energy problem. Condensation heat utilization technology can improve energy utilization. It can achieve high efficient use of energy if use these two technologies toghter.This study analysize some key problems,aiming at condensing heat application in the system of water source heat pump. Firstly, compare the present commonly used type of condensing heat recovery systems and condensation heat utilization and analysize key factors influencing condensation heat. Using A.C.Cleland formulas to establish mathematical model of thermodynamic analysis of condensation heat utilization, and has developed appropriate software. Condensing temperature, water temperature, and air conditioning loads were analysed which are key factors influencing condensation heat utilization. It demonstrates how they are affecting condensation heat utilization.At the same time, technical measures that improve water source heat pump condensation heat utilization efficiency were proposed for the critical factors, which mainly reflected in the hot water temperature control, recovery system control and regenerative heat system control. The optimization method were proposed of practical engineering condensation heat utilazation, which is based on best matches between engineering needs for hot water and the ability of units condensing heat supply to determine the optimum water flow and water temperature, and take an instance of a real project , analysize the optimal condensing heat utilization scheme. It also analyzed the economic benefits of the use of condensing heat and energy saving benefits. It conducted experimental study of condensing heat use of water source heat pump , analysized the unit operating parameters and water temperature characteristics, as well as unit energy efficiency and systems integration efficiency. And made a method by optimizing the operating parameters, to improve unit energy efficiency. Exergy analysis equation of each component is established, compared exergy losses and exergy efficiency of single cooling mode and condensing heat utilization mode.The results show that: direct part heat recovery with double condensermeans less investment, has small impact on the stability of units, which is suitable for water source heat pump condensing heat recycling. Evaporating temperature and condensing temperature and condensing heat load have inverse relationship, and degree of undercooling and overheating have little effect on condensation heat load. Increase of condensing temperature and conditioning load are conducive to the improvement of condensation heat recovery, but high condensation temperature and high temperature hot wateris negative for unit efficiency. Considering from the lower condensing temperature, return water temperature control is better than the hot water temperature control , in order to determine the extent of hot water temperature, energy efficiency considered as a judgement ,take to a unit as an example, the calculation result of hot water temperature control is 50℃-54℃. By comparing different heat recovery system control schemes, take energy efficiency and hot water demand into consideration, give proitiy to heat recovery quantity control is the optimal scheme, which meet the water demand and unit energy effiency. proposes a heat storage device design method for dismatch between avirable Condensation heat and hot water needs , by optimizing condensing heat utilazation of a real project, the optimal water temperature is 57.8℃, the optimal flow of 1.24kg / s. Exergy analysis showed that the compressor and condenser exergy loss is the largest in the water source heat pump system, which is the main direction to improve energy efficiency. Condensation recovery can reduce the condenser thermal exergy losses; improve system exergy efficiency, comared with single cooling mode, system exergy efficiency of condensation utilazation mode increase from 38.1% up to 43.5%...