Research On Operation Modes And Pipeline Leak Detection In Central Heating System

As China’s sustained economic development, energy and environmental problems become increasingly prominent. In the building energy consumption in our country, the energy consumption for heating the largest proportion, and the unit of residential building heating energy consumption is about 3 times the same climatic conditions in developed countries, so the research on energy-saving of central heating system should be imperative. The central heating system consists of heat source, heat supply network and hot user of three part, this article proceed from the composition of central heating system, studied the syetem of heat source regulation mode, heating pipelines leak positioning and heat users’room temperature control, bathing waste water waste heat recovery separately.Research paper includes the following aspects:In view of the heat source energy saving control, established phased quality flow dynamic adjustment model, using Matlab software for simulation calculation of the dynamic model, and got the change rule of supply, return water temperature and flow with the outdoor temperature changes. By changing the flow of quality regulation in stages, staged mass-flow homeostatic regulation and dynamic adjustment three kinds of control method and analysising comparatively the secondary network system power consumption and heat coal consumption, Obtained by stages of mass-flow dynamics regulation mode in the heat source, the secondary network system power consumption, heat coal consumption, pollutant emissions are the least,and the energy-saving is more obvious.In order to analyze the method of leakage location, the comprehensive experiment heating pipeline leakage detection system is built. The methods of multi-population hybrid adaptive genetic algorithm and mixture adaptive genetic algorithm are used to do the identification of resistance in heating pipeline. The experimental results show that the two methods of genetic algorithm could improve the accuracy of identification. And the multi-population hybrid adaptive genetic algorithm has the higher accuracy.The matrix of resistance which is used in heating pipe line is built on the base of graph theory and hybrid adaptive genetic algorithm. The variations of working conditions in different running conditions arc simulated. The change rule of the pressure of heat exchange station entrance in the leakage condition of water supply pipe is calculated. The change rule of pressure differential of heat exchange station entrance and outlet, flow is calculated too. The leakage section could be located with this change rule. Then, the leakage location model is built on the base of pressure gradient. The leakage point could be found with this model. At the end, the experiment is used to show the accuracy of those theories. The experiment result expresses that the change rule is right. The maximal error of the location of leakage point is 5.54%. The minimum error of the location of leakage point is 0.25%. This theory meets require of heating engineering.