Research And Application Of The Device With Water Jet Pump And Variable Frequency Pump In District Heating

At present, building energy consumption accounts for about30%of total energyconsumption of social goods in china, where energy consumption heating in northern regionaccounts for about40%. The overheat loss caused by thermal imbalance accounts for about25%of total energy consumption of heating, and to a certain extent, reduce the heating quality.Heating energy consumption increased rapidly with the fast development of urbanization,resulting in deterioration of the atmospheric environment in winter, such as in2012, there isserious "haze" in winter of Beijing. Therefore, the energy efficiency of heating system is animportant part of building energy saving in china.Between the buildings and the heat users proned to occur thermal imbalance in thetraditional heating system. The conventional solution is to increase the circulating water flow,and installed balancing valve at the near end user entrance in order to solve the problem ofheat imbalance. It led to an increase in power consumption of circulating pump in a largeextent, and larger heat loss. In view of this, this paper proposed a heating system with the jetpump and pump combining with the poor regulation performance of jet pump, to increase thecirculating water flow of heat users and solve the thermal imbalance problem in building,reducing the heat loss.Based on the one-dimensional theory of jet pump, this paper found mathematical modelof jet pump and pump, and modified it by experimental data. Using the calculation program toanalyze the influence of heating parameters on the performance of jet pump. This paper tookthe vertical single-pipe heating system of a six story residential building as an example, toanalyze the working effect of the heating system with jet pump and pump and adjustingmethods. The results show that, the thermal imbalance is smallest when mixing ratio is0.4. Atthe same time, it analyzed the relationship between the surplus pressure difference atentrance, he highest mixing ratio of jet pump,and the minimum pressure of pump.The results of this study provides the technical proposal to solve the thermal imbalancein building, and theoretical guidance for the actual reform of heating engineering.