Simulation Study Of Heating System Of Trough Solar Collectors Combined With Gas Boiler

Increasing scarcity of energy resources and the gradual deterioration of ecologicalenvironment has become a serious challenge to sustainable development of humansociety, the development and application of new energy and renewable energy will bethe key measures to address energy and environmental issues. Solar energy is aninexhaustible clean energy, which has aroused extensive attention; Especially in severecold regions of northern China, the use of solar heating has significant implications forreducing conventional energy consumption and air pollution mitigation, and will makean important contribution to energy saving and environmental protection work forthose areas.In this paper, a novel heating system of trough solar collectors combined with gasboiler is proposed, which can solve the problems caused by the application oftraditional solar collectors in severe cold area, including great heat loss, low efficiency,difficult antifreeze, easy to clog, tube explosion, low reliability etc. This paper aims toconduct a detailed simulation study on the operation characteristics of the novelheating system, and to achieve maximum system energy efficiency and economicbenefit by optimizing the components and associated control measures.Firstly, the principle of the novel heating system has been elaborated, and basedon a residential building after energy saving transformation in Hebai residential district,Harbin, selection calculation has been taken for the various components of the heatingsystem, including detailed design and installation analysis of the solar collectorsystems, building heating systems and heat transfer equipments; At the same time, avariety of operation modes and corresponding control strategies has been proposed tomake the system run more reasonable.Based on the energy conservation law and corresponding mathematicalknowledge, accurate mathematical models have been established for the variouscomponents of the system, and the operation characteristics of the system in typicalmeteorological year’s heating season have been simulated using MATLABprogramming software. The relationships of building load and effective heat gain,collector efficiency, solar fraction, heat storage tank temperature, the running time of each mode, heat for heating and energy consumption and economy etc have beendeeply studied, and the overall running performance of the system has beencomprehensively assessed.Finally, four aspects, including collector area, storage tank volume, system controlstrategies, have been optimized to further improve system performance; After overalloptimization of the system, solar fraction has improved significantly and energy savingand economic benefits have been more significant.This paper belongs to the12th Five-Year Plan National Science and TechnologySupport Program Project "Research and Demonstration on technologies of GreenRetrofitting for Existing Residential Buildings in Typical Climate Zones"(NO.2012BAJ06B02).