Study On The Relationship Between Human Perception And Thermal Comfort In Micro Buildings Based On The Space Around People

In 2022,the world ’s population has passed the 8 billion mark.With limited land resources and a growing population,the relationship between land and population is becoming increasing close.’ More people and less land ’ is the common problem faced by many countries around the world.As the global urban population continues to grow,the new architectural design concept-miniaturization and miniaturization has become an important direction for the development of the construction industry in order to alleviate the contradiction between land and population effectively.In micro buildings,the basic purpose of indoor thermal environment is still to meet the requirements of human thermal comfort.As a direct factor affecting human thermal sensation and comfort,the indoor thermal environment parameters will have a more significant impact on human thermal comfort in miniature buildings.In fact,most of the heat in the human body will be dissipated through conduction,convection,radiation and evaporation,affecting the thermal environment to a certain extent.Based on the theory of human thermal comfort,this paper investigates the thermal environment of near-body space,which is directly affected by the heat dissipation from human heat source in micro-buildings.On this basis,the influence of temperature and color factors on human thermal comfort is studied and analyzed,which provides reference for the indoor thermal environment regulation of micro buildings.In the experimental study of the thermal environment of the space around people of micro buildings,the influence of human body heat dissipation on the indoor temperature field is explored based on the human body heat source.In addition,this paper analyzed the convection and radiation heat transfer between the human body and the environment theoretically.The results show that when the height and the orientation of the human body are constant,the air temperature in the near human space has a nonlinear relationship with the distance from the human body,and the temperature decreases exponentially with the increase of the distance.In the drawn air isotherm around the human body,it is found that when the temperature difference between the adjacent isotherms is equal,the closer get to the human body,the denser the isotherm is.The convective heat transfer coefficient of human body surface is an important guideline for the study of human thermal comfort.Combining the experimental measured temperature data with the influence of human heat dissipation,the formula for calculating the convective heat transfer coefficient of human body surface is modified.When calculating and analyzing the average radiation temperature parameters used to evaluate human thermal comfort,based on the principle of heat balance,we calculated the average radiation temperature of this experiment using definition method.Combined with the PMV model,it is found that for human thermal sensation to remain constant,The change of mean radiation temperature and air temperature in near space should satisfy the following relationship.When the air temperature in the near human space decreases(increases)a certain temperature.The average indoor radiation temperature can increase(decrease)the corresponding temperature,so that the thermal sensation of the human body remains unchanged.This conclusion helps to optimize the interior design temperature standard,so as to achieve the purpose of energy saving.In the study of the composite factors of temperature and colour on human thermal comfort,based on the orthogonal experimental design method,the thermal environment of three temperature levels of 16.21,26℃ and a total of ten environmental color of red,orange,yellow,green,blue,purple,black,white and gray are combined to explore the influence of thermal environment at different temperature levels on human thermal comfort under the same environmental color,and the influence of different architectural space colors on human thermal comfort at the same temperature level.The results show that when the environmental color is certain,the voting value of human thermal sensation becomes larger with the increase of temperature in the thermal environment.Under the thermal environment of 16℃ and 26 ℃ temperature levels,the human thermal sensory vote values for the different architectural space colors are relatively close,while at 21℃,the thermal sensation voting values in the environmental colors of red,orange and yellow are less different,and the thermal sensation is warm.The thermal sensation voting values of green,cyan and blue are close,and the thermal sensation is cool.The thermal sensation in the environmental colors of purple,black,white and gray is neutral.In addition,in the analysis of the influence of two factors on human thermal comfort by two-way analysis of variance,the difference between the influence of temperature and color on human thermal comfort is further examined.The thermal environment at 16,21,26℃ has significant influence on human thermal sensation.When the indoor air temperature is at 21℃,colour tones are significantly correlated with human thermal sensation,while there is no significant difference between the colour tones and the human thermal sensation at the 16℃ and 26℃ temperature levels.In the study of the influence of color and temperature on human psychological parameters,it is found that when the wavelength of color changes from large to small or from small to large,the heart rate changes from small to large or from large to small,and the change direction of heart rate is opposite.When the color of the building space changes from white to red,orange and yellow in warm tones,the blood pressure level of the human body will increase,especially in female subjects;while in green,cyan and blue ambient colors,the human blood pressure value will be reduced to a certain extent.In addition,under the compound effect of color and temperature,the thermal comfort zone of the human body will shift.Compared with red,orange and yellow tones in warm colors,the upper limit of thermal comfort temperature of cyan,blue,purple,black,white and gray tones is higher,offering certain energy saving potential.In the numerical simulation research,this paper establishes a physical model based on the actual size of the micro building laboratory bench.The position of the human body inside the model corresponds to the experiment,and the heat dissipation of the human body is set according to the posture.This part of the heat is attached to the energy equation,and the indoor temperature and air flow rate with human body heat dissipation are simulated numerically.The results show that the convective heat transfer between the human body and the surrounding air not only affects the temperature distribution in the near-body space,but also that the part of the hot air close to the human body is less dense and has a tendency to float upwards due to the heating effect of the human body.