The Analysis Of Dynamic Hydraulic Balance In District Heating System

Construction energy conservation is the major measures in energy conservation and emission reduction. However, energy saving in heating is one of the most potential and the most effective way in our country building energy conservation, in order to realize high efficiency, stability and energy saving heating network system operation, meet the thermal heating demand of users, the selection of strategies and methods of adjusting and controlling of the network system will directly impact to the overall energy saving effects of the system.Therefore, this paper puts forward to research the change that caused by the change of electric valve when adjust and control the heating pipe network system, to find out is there any delay of pressure and flow among the heat exchangers which one of them is changed by change the opening degree of electric valve. This research is aimed at providing a optimization method, in the adjusting and controlling the heating pipe network system, to enhance the hydraulic stability of the pipe network and save energy by considering the effect of hydraulic that changed by the changed of opening degree of electric valve on the other heat exchangers.This paper treats the indirect connection pipe network system as the object and construct a small model of indirect connection pipe network system in the Lab which radius is 45 meters. This pipe network system is equipped with many electric valves and other sensors such as pressure, flow and temperature, so you can try many strategies and methods of adjusting and controlling the network system through the computer, and also the data detection. So you can realized the experiment of pressure, flow and pump by change the speed of pump or open degree of electric valve so that you can explore the dynamic response of pressure and flow among the branch pipes.In order to make the conclusion more practical, process and analyze the recorded data which provided by Xi’an Thermal Inc. and then draw a conclusion to contrast with experiment conclusion.The result of research show that for the branch pipe network system, there is delay of the pressure among branch pipes, namely, when the valve’s open degree changed, the pressure of other heat exchangers changed after some time, which is relate to the distance and location of heat exchangers. But there is no delay among branch pipes when the rate of flow changed.