Effects Of Heat Source Characteristics On Indoor Thermal Environment And Human Thermal Comfort Of Micro Buildings In Winter

In the densely populated and expensive modern society,the miniaturization of buildings has become a trend.The adjustment of the national fertility policy in 2016 has intensified people's demand for small buildings."Micro building" is different from the general sense of small houses Under the premise of very small area,such buildings can have personalized interior space,which is conducive to energy saving.material saving and land saving.and more suitable for the city;life with strong mobility,which have large capacity of expansionIn the winter in most non-hot areas of China,the indoor thermal environment of micro buildings is difficult to meet the requirements of human thermal comfort without heating source This paper studies the indoor thermal environment and human thermal comfort in micro building by adding three kinds of heating equipment,such as oil heater,radiation heater and fan heater,and considering other heat sources such as computer,TV,electric lamp and human body,Firstly.this paper analyzes the influence of different heat sources in micro buildings on indoor thermal environment and human thermal comfort through experimental method.The experimental test includes two parts:parameter measurement and questionnaire survey.The parameter measurement includes the test of indoor temperature,relative humidity and wind speed.The questionnaire survey includes the thermal sensation and thermal comfort of human body in the building.Based on this,Origin 9.0 is used to conduct data integration and regression,and the following conclusions are drawn(1)In the micro building,when heat source is added,the temperature in the upper part of the room is higher than the temperature near the ground,and the temperature near the ground is higher than the temperature in the middle of the room.For different grade of oil heater,radiation heater and fan heater,the law of the temperature distribution is roughly the same.(2)The relative humidity is obviously affected by the distance between the measuring point and the heat source(3)Under the effect of forced convection,the average level of indoor air velocity will increase to some extent,while even the heat sources are added,the improvement of indoor air velocity is not obvious only by relying on natural convection.(4)Human thermal sensation is not only affected by temperature,but also by the comprehensive influence factors such as relative humidity,wind speed.distance from the heat source and other factors.For different part of the human body,the thermal sensation has a certain difference.The thermal comfort of the head has a small change range on the whole,and is basically in a slightly uncomfortable or comfortable state.The thermal comfort of hands and feet changes significantly.The overall thermal comfort changes with the local thermal sensation.(5)In the micro building,the room with heat source is more comfortable than the room without heat source,but it is not that the greater the heat source power,the more comfortable the indoor human body feels,and then,more factors need to be considered.Contrast to the radiation heater and oil heater,the fan heating makes the human body feel comfortable for a longer time.This is because the heat of the fan heating is mainly transferred by forced convection,thus the indoor airflow is more uniform and stable.In general,the human body can basically feel comfortable for all above three kinds of heat sources,after the heat source is turned on for a period of time,which is no more than 30 minutes.Then,through the Airpak software,the indoor thermal environment and human thermal comfort of the three kinds of heat sources at different grades is simulated.The conclusions are drawn as follows:(1)Contrast to oil heater and radiation heater,the indoor air temperature distribution of fan heater is relatively more uniform,for the different grade of three kinds of heat sources,the temperature of the upper part of the room is lower than the temperature of the lower part of the room.(2)From the vertical section,the average level of relative humidity of the lower part of the room using all the three kinds of heat sources is lower than that of the upper part.In the horizontal section,contrast to the oil heater and radiation heater,the indoor air relative humidity distribution of the fan heater is relatively more uniform.(3)The overall level of air velocity in the upper part of the room is lower than that in the lower part of the room.For radiation heater and oil heater,the air velocity of positive and upper direction is relatively larger,and that of the lower part of the room away from the heat resource and the upper part is lower.And in contrast,the air velocity of the upper part of the oil heater is comparatively larger.For fan heater,the air velocity near the outlet area is very large,obviously larger than the first two kinds of heat sources,and the diffusion range of air velocity is also significantly larger than the first two kinds of heat sources.(4)When using oil heater,the effect of thermal sensation of legs and head using is best,while using radiation heater with low grade,the effect of thermal comfort near the legs in front of the heater is better.(5)Thermal dissatisfaction was significantly lower which is close to the human body than in the rest of the room.For radiation heater,the legs are less satisfied,and most people are satisfied when it is in high grade.For the fan heater,the dissatisfaction degree is lower than the radiation heater when the heat power is similar.For oil heater,the overall dissatisfaction is the lowest,when oil heater is in high grade,the overall dissatisfaction are increased instead due to the lower part of the human body produces thermal sensation in a way.By comparing the experimental results with the simulated results,it is found that the temperature and relative humidity between them are basically similar,but due to some uncertain factors in the experiment,the deviation of air velocity is relatively large.The results can provide certain data support for the design in indoor thermal environment,and can also provide certain guidance for the development of this kind of buildings.