Study On Typical Wall-mounted Boiler Heating System In Middle Ang Lower Reaches Of The Yangtze River Region

Most area of the middle and lower Yangtze River basin in China belongs to the hot summer and cold winter zone by building thermal partition. Winter weather of this region is cold and wet. It is the coldest in the same latitudes of the world. Although inclement winter weather conditions, the area does not belong to the central heating zone due to historical and economic reasons. With the improvement of living conditions for Thermal comfort requirements, all kinds of heating forms was flourished to meet the heating needs of the residents in the region. Using wall-mounted gas boiler as heat source. It can be combined with various heating radiators. Because of its characteristics such as easy installation and flexible use, it adopted by a growing number of residents, and has become an important heating form of middle and lower Yangtze area home. This research includes the application situation, run rules, indoor thermal environment, economics and applicability. The specific content and relevant conclusions are as follows.(1)Selected Changsha, Wuhan and Yangzhou as typical representative city. Conducting surveys of household gas heating applications by means of a questionnaire. Survey suggests that the proportion of Steel plate radiator, Copper Tube convection radiator and Radiant floor is larger, accounted for 53%, 22% and 14 % respectively in the investigation. According to the survey results of indoor thermal environment, 77% users indoor temperatures between 20℃ and 24℃,97% users indoor relative humidity between 30% and 70%. meet the requirements of temperature and humidity in GB/T18049-2000.From the residents subjective evaluation feeling about hot and cold, humidity, airflow satisfaction, it can be drawn that household gas heating methods application effect is very ideal in this region.(2)Use three kinds of heating methods in Changsha city as the research object, to test the heating operation rules and distribution characteristics of temperature and humidity. Using the PMV theory and Level II Thermal comfort requirements as comfort range, based on regression equation of PMV and indoor air temperature, we can calculate that the indoor comfort temperature range of Steel plate radiator is 18.5~21.3℃,the indoor comfort temperature range of Copper Tube convection radiator is 19.1~22.2℃,the indoor comfort temperature range of Radiant floor is 17.0~19.3℃.(3)Using numerical simulation method to analysis the simulation of indoor thermal environment under three forms of heating. Under the same heat dissipation, the main areas of indoor air temperature from high to low order are: Copper Tube convection radiator, Radiant floor and Steel plate radiator; radiation temperature from high to low as follows : Radiant floor, Steel plate radiator, Copper Tube convection radiator. Through the analysis of three kinds of heating methods such as temperature, speed and PMV, summarizes the characteristics and rules of different heating methods.(4)Analysis the economy of three typical household gas heating methods. Designing three typical heating methods and calculating their initial investments and operation costs. On the calculation period of 60 years, we calculate the cost of three kinds of heating methods. The results showed that wall-mounted gas boiler with steel plate radiator heating system has an advantage more than the other two forms in initial investment, operating costs and the cost of lifetime.(5)Combining the characteristics of three kinds of heating methods and making a comprehensive assessment and analysis of the applicability of different ways. Provide reasonable guidance to designers and users of this form of heating.