Study On Comparative Of Heating Exchanging Pattern And The Settings Of Circulating Pump In District Heating System

In view of the serious hydraulic maladjustment, large energy consumption and lower heating efficiency of heating network presently and such problems, this paper studied on the core part in the central heating—heat exchanging pattern and reasonable setting of circulation pump of network distribution system.(1)Direct connection heating system, indirect connection heating system and installing the mix water pump of heating system was analyzed, configuration scheme of installing the mix water pump of heating system was proposed, including the mix water pump was set at the bypass pipe which is suitable for occasions of high-medium pressure area of a network supplying water and little difference of the terrain, the mix water pump was set at secondary supplying water network which is suitable for occasions of low pressure area of a network water supplying and the mix water pump was set at secondary backwater which is suitable for occasions of high pressure area of a network supplying water and low lying terrain.(2)This paper applied law of conservation of energy and mass, with the direct connection heating system, indirect connection heating system and installing the mix water pump of heating system as the research object, and established simulink dynamic simulation model with boiler, pipe, heat exchanger, indoor temperature and water pumps and other part, it is concluded the important characteristics of three different heat exchange pattern in the same outdoor environment and heating conditions. We can established boiler water supply temperature and Fuel Consumption than curve, the time delay graph of indoor air temperature reached steady-state, water supplying temperature and flow adjusting curve. Combining with the project example, showing mix water heat transfer system is of great flow, small temperature difference operation, energy saving potential is big. Large mixing ratio of heat mix water connection undoubtedly becomes the first considerate heating way especially for the different heating ways users in the gained or new heating area.(3)This article through the several common network distribution system from energy consumption, investment cost, operation of electricity and equipment recovery period, etc. carry out comprehensive comparison analysis.Drawing pipe distribution system of more heat exchanger station seting mix water of variable-frequency pump in the current situation is worth extending, which have great energy saving space. Taking the distribution system ten users of as an example, the investment of pipeline network system with mix water frequency-pumps is greater, which is twice great than setting the circulating pump along water supplying network of the distribution system and recovery period is short of 0.19 years, energy-saving effect can achieve 75%, So the distribution system of setting mix water frequency-pumps in heat exchanger station is worth extending.(4)Hydraulic coupled thermo-mechanical between the different mix water pumping station and the interference of the flow quantity or heat between different pump in the pipes make system adjustment and the control strategy is very complex, this articlie used the mode of variable flow adjusting. Users of many mix water heat transfer station systems from near to distant for heat source and their mixing ratio in turn reduce. Mixing flow and a flow supplying by an increase and increasing extent is different because of the length of the pipe network. Meanwhile, heating pipe is adjusted in advance based on thermal inertia of the piping and huge buildings to adjust.