Research On The Western Solar Heating Potential Based On Building Shape Elements

Due to the rapid development of urbanization,the natural underlying surface of the city,such as grass and soil,is constantly replaced by impervious cement,asphalt and paving bricks,etc.,which changes the radiation field of the underlying surface of the city and changes the heat transfer process of the underlying surface,leading to the intensification of urban thermal environment problems.It will affect the physical health and work life of urban residents.This paper takes Xi ’an University of Architecture and Technology as the measuring point to study the environmental thermal effects of radiation fields of different underlying surfaces,which provides scientific basis for the construction of urban thermal environment,and has certain reference significance for the selection of urban underlying surface types and the planning and construction of urban thermal environment.Firstly,in order to study the differences of radiative thermal environment of different cities’ underlying surfaces,this paper analyzes the process of thermal action of different underlying surfaces based on field tests of radiative thermal environment of different underlying surfaces of Xi’an University of Architecture and Technology in Xi’an in summer and winter.Through the study,it is found that the heat absorbed by the lower mat surface mainly consists of the absorbed atmospheric inverse radiation and short-wave radiation,and the amount of atmospheric inverse radiation accounts for more than 65% of the total heat absorption.The heat exchange between the lower cushion surface and the surrounding environment is mainly carried out through the heat exchange by radiation,and the heat exchange occurred in the way of radiation heat exchange in all four types of lower cushion surfaces is more than 75%.Secondly,in order to quantitatively analyze the differences in the intensity of radiant heat action on different sub-bedding surfaces,the sub-bedding surface radiant heat index is proposed.By calculating the time-by-time radiant heat index of different lower cushion surfaces and analyzing the correlation between the intensity of radiant heat action and horizontal total solar radiation and air temperature,it is found that the relationship between radiant heat index of lower cushion surface and horizontal total solar radiation is stronger,and the correlation between radiant heat index and total solar radiation is basically around 80%,so this radiant heat index can evaluate the strength of radiant heat action of different lower cushion surfaces.Finally,ENVI-met is used to simulate the degree of influence of different enclosed spaces,different building heights and different thermal physical parameters on the radiant heat environment.The specific conclusions are as follows: Based on the evaluation index of radiant heat effect to calculate the intensity of radiant heat effect of four kinds of underlying surfaces,it is found by comparison that the radiant heat effect of concrete underlying surfaces is the strongest and the radiant heat effect of grass underlying surfaces is the weakest,no matter in winter or summer.By simulating different reflectance,long-wave emissivity,thermal conductivity and volumetric specific heat capacity of the four types of underlying surfaces,it is found that the thermal physical parameters of different underlying surfaces materials have different radiant heat effects on the underlying surfaces.By simulating the effects of different building enclosure spaces and building heights on the radiant heat environment of the lower mat surface,it is found that the arrangement of the lower mat surface materials can give priority to the arrangement of the grass lower mat surface under the premise of meeting the functional and usage requirements.In summary,the thesis investigates the difference of radiant heat effect process of different underlying surfaces,and proposes the radiant heat index of underlying surface to quantitatively analyze the difference of radiant heat effect of different underlying surfaces,and finally proposes the optimization and creation measures of radiant heat environment of underlying surface through simulation analysis.