Research Effect Of Low Temperature Floor Radiant Heating In Gannan Region

Gannan region is located in the south of jiangxi,which belongs to hot-summer and cold-winter zone,the summer heat,winter cold and perennial humidity,it is classified as non-heating zone,indoor thermal comfort was poor in winter.To improve the indoor thermal environment,the residents of the area began to use air conditioning,heater and fire to keep warm,however,these methods have also caused new problems such as indoor thermal comfort and building energy consumption.Low temperature radiant heating is a relatively mature heating method in the present,it can use all kinds of low grade energy and heating effect is obvious,at present it is seldom used in Gannan area,therefore how to prove the low-temperature radiant heating system in Gannan area has use value,and combined with the region climate and geographical features of the low-temperature radiant heating technology is utilized to improve indoor thermal comfort and building energy consumption issues worthy of our in-depth study.So we have a survey of the region to understand whether the region has the need for heating,and on this basis,further study the effect of low temperature radiation heating,the following conclusions are obtained:Firstly.Investigation and analysis of indoor thermal environment in winter in Gannan area.Statistical analysis of the subjective evaluation of indoor thermal environment in the area and the necessity of heating,thermal comfort and the changes of indoor thermal environment and the influence on human thermal comfort.The results show:Comprehensive consideration the indoor thermal environment in winter and the influence of the health of human body before and after heating,59% of them think that it is necessary to have heating in winter.Indoor heating to air conditioning(33%)and followed by the floor radiant heating,while the use of fire and heating is less.For different heating methods,the respondents were given different comfort degree evaluation,relatively speaking floor radiant heating indoor comfort evaluation is higher.Secondly.Numerical simulation of indoor thermal environment.Combined with the Gannan area winter climate and geographical features,separately carries on the numerical simulation of the two kinds of heating system of indoor thermal environment by using the theory of numerical simulation,and through the field experiment to validate the numerical simulation model boundary conditions set by therationality;finally,combining the subjective evaluation of human body to analysis the indoor thermal comfort factors such as the distribution of air humidity,temperature,flow rate.The results show:the distribution of indoor air temperature,humidity,flow rate were influenced by the climate conditions,however,the different indoor influence of heating mode is different,and it is compared with the air conditioning heating system in the low temperature floor radiant heating system:The distribution characteristics of air temperature can meet the requirements of human comfort temperature(18~24?),and the average air temperature is higher than the air temperature at the same time of 2~3?.The air humidity can be reduced by the air temperature distribution,but it can meet the requirements of the comfort and humidity(30~60%).The concentration of carbon dioxide in the range of human activities is smaller(104~108ppmv).Overall the indoor thermal environment distribution can meet the requirements of human comfort.Thirdly.Evaluation and analysis of heating system.The results show that compared with air conditioning heating:The distribution of PMV-PPD in the heating chamber is influenced by the outside climate conditions,the more close to the wall,the more obvious the effect,but in the area of low temperature floor radiant heating system can meet the requirements of comfort.The same indoor temperature,low temperature floor radiant heating system can save up to 15% of energy.Low temperature floor radiant heating system is high,but low operating cost,and the service life is long,in the long term,the cost of the use of the process is low,with good economic benefits.