Experimental Study On The Influence Of Air Flow On Human Thermal Sensation

With the development of economy and the advancement of science and technology,the urbanized life makes people spend more and more time indoors,which makes the research on the thermal sensation of the indoor environment begin to attract more and more people’s attention and attention.Natural ventilation and ceiling fans are routine cooling methods in summer classrooms.However,they are rarely seen in the current new teaching architecture design.The reason is that basic research in this area is not enough,resulting in the lack of relevant guidelines.Due to the limitation of experimental conditions,the experimental results obtained by the indoor environment on human thermal sensations are quite different from the actual situation,and there is generally a greater degree of randomness and subjectivity.When researching and exploring the thermal sensation of the human body in the indoor environment,identify as many factors as possible that affect the final result,make the experimental conditions closer to the actual situation,and the results obtained will be true and reliable,thus providing the new teaching architecture design reference.In this paper,on the basis of the existing experimental conditions,to join the average skin temperature,core temperature and skin moist degree,three thermal physical parameters of environmental impact is significant and an experimental study of indoor environment on human thermal sensation.In Tianjin University,24 students dressed in typical summer clothes were organized to simulate the learning environment of the classroom.The cabin temperature is 26 ℃,28 ℃,30 ℃,32 ℃,relative humidity was 70%,under the experimental condition of the three physical parameters were tested.At the same time,the author studies the influence of ceiling fan on human physiology and psychology from both subjective and objective aspects.The contents of the questionnaire include human thermal sensation,airflow acceptability,wind speed expectation,etc.Four kinds of wind speed were selected in each temperature condition,and the orthogonal table was arranged according to the exposure order to eliminate the influence of the order of wind speed on the experimental results.The results show that strengthening the air flow can improve the thermal sensation of the body and reduce the thermal sensation of the body,but it is not the better the air flow speed is.Under different temperature conditions,the air flow velocity has a preference value.At the same time,the average skin temperature,core temperature and skin wetness decreased with the increase of wind speed.However,as the temperature increases,the decrease of physiological parameters decreases.In addition,the subjects in the cabin temperature 28 ℃ and 30 ℃,32 ℃ respectively the preference when wind speed: 0.85 m/s,1.0 m/s,1.2 m/s,;Far higher than the 0.8m/s limit set by ASHRAE standard.