Key Equipments Optimization Of Solar Ground Source Heat Pump System In Severe Cold Regions

In China, nearly 70 percent of the region need winter heating. And most of these areas need coals as their main fuel of heating, therefore, which definitely exacerbated the fossil energy consumption and natural environment pollution. In this context, this paper presents a new energy-saving and environmental protection heating system, that is, Solar-Ground Source Heat Pump (SGSHP), which is based on solar energy as the main heat source and the soil heat as an auxiliary heat source. Meanwhile, this system stores solar heat which is collected in spring, summer and autumn into the underground soil by the underground heat exchanger, subsequently extracts them with heat pumps in winter, All of the heat is used for heating, Cooperating with with solar heating system, which effectively implements the utilization of the heat of every seasons.First of all, the paper begins with the data of experiments, addresses three major subsyetems of SGSHP. Meanwhile, it constructs three different operating patterns through plate heat exchangers and heat pumps. In addition, it combines theory with practice, establishes parts of mathematics models of SGSHP and forms the three kinds of modes mentioned above while controlling the switches through temperature parameters. Furthermore, the research compares the simulation results that run for nearly one year with experimental results, then selects representative issues to unwind specific analysis and then verifies the reasonableness of models. The last step, which is also the key point in this system, is to optimize the SGSHP heating system which contains the angle, area and heat pump power of solar collectors. Meanwhile, the paper sets system average COP, cost fees, imbalance rate of soil heat transfer and the rate without guaranteeing indoor temperature as four comprehensive evaluation indexes. The ultimate optimization results, the angle, area and heat pump power of solar collectors are 54°, 53m~2 and 2.2kw, respectively.Although the SGSHP system is a novel heating system, it has been not widely used in practice because of the economic cost and other reasons. At present, with the increasing depletion of conventional energy, gradually rise of energy prices and the augment of environmental pressure, as well as constantly improvement of Solar-Ground heating system and radiant floor technology and decrease of heat collector prices, the SGSHP system must become a kind of highly competitive heating system. Consequently, this research provides theoretical basis and technical support for the future.