Dynamic Water Temperature In Surface Water Source Heatpump Systems Utilizing Stagnant Water

With the development of the word economy, the world is facing environmentalcrisis and energy crisis. So energy conservation and sustainable development hasbecome an inevitable trend and renewable energy is in good graces of people. China isabundant in surface water resources, such as Yangtze River Basin, Yellow River Basin,Heilongjiang Basin, Huaihe Basin and so on. In recent years, the development of thesurface water source heat pump air conditioning system gets the attention in our country.But because the system theory is lack of research and engineering application is still inengineering exploration stage, there are some problems in the actual operation, and thuson the system energy conservation and application promotion ultimately.At present, the research on the water temperature calculation model is more, butthe research on heat-cold carrying capacity of stagnant water is less. This paper ismainly for4m to10m depth stagnation water as the research object, based on the opentype surface water source heat pump system, analyzes the heat-cold carrying capacity ofstagnant water under the different water temperature, different water depths anddifferent energy saving rates. The main research contents and conclusions are asfollows:①Analyze the characteristics of the stagnation water, including water quantity,water temperature and water quality. It’s necessary to analyze and master the influencefactors of the cold carrying capacity of stagnant water. The main effect factors are theinitial water temperature, water quantity and water allowable upper temperature. Itneeds to comprehensive considering over factors when calculating the cold carryingcapacity of stagnant water.②With the surface stagnation water as the research object, Chongqing universityWuhao only establish the water temperature control equation, but not discrete the N-Sequation. In this paper, based on the N-S equation and the water temperature controlequation, using the numerical calculation method to scatter the equation, the flowcontrol equation and the water temperature equation are coupled solution. The water2-dmodel is built though the MATLAB software to calculation the water temperature. Inthe natural condition, the2-d model numerical calculation results is close to the3-dmodel numerical calculation results when verified the correctness of2-d model by theexperimental date and3-d model. So in order to analysis the project facility,2-d model can be used completely.③Using the equipments of the open-loop surface water source heat pump systemand the conventional air-conditioning system (such as heat pump, water pump,end-equipment, cooling tower, etc) as the analytical objects, the energy consumptionmodels of each equipments are set up and the method on how to calculate the waterintaking temperature limits in different energy saving rates is ensured. The limit waterintaking temperature is calculated in different energy saving rate of one practical project,prepared for the next chapter to calculate the water maximum heat carrying capacity.④Based on the water2-d model and water allowable upper temperature, themaximum heat carrying capacity of stagnant water is calculated under different waterdepths, the different initial water temperature, and different energy saving rates. Get thefunctional relation between the maximum heat carrying capacity of stagnant water andwater depths, initial water temperature and energy saving rate. In addition, the influenceof the lake different cross-sections for the maximum heat carrying capacity of stagnantwater is analyzed. It is revised by comparing the maximum heat carrying capacity oftrapezoid section and rectangular section in the condition of the same depth, initialtemperature and energy saving. It has important significance for the research of thewater source heat pump system, and provides the reference for engineering design.