Developing a method for calculating the mean outdoor radiant temperature for thermal stress in Guangzhou  

作　　者：Xiaoqing Zhou Tianwei Tang Xiwen Feng Naiping Gao Yanping Yang Zhaosong Fang 

机构地区：[1]School of Civil Engineering and Transportation,Guangzhou University,Guangzhou,510006,China [2]School of Mechanical Engineering,Tongji University,Shanghai,200092,China

出　　处：《Building Simulation》2024年第11期1989-2006,共18页建筑模拟（英文）

基　　金：supported by the National Natural Science Foundation of China(Project No.52278097);National Key R&D Program of China(Project No.2023YFC3805304-2).

摘　　要：Cities around the world are exposed to increasing heat stress as a result of the heat island effect exacerbated by extreme weather events,population growth and increased urbanization.To promote outdoor activities and protect human health,there is an urgent need for a tool to assess the outdoor thermal environment.While the air temperature(Ta)and relative humidity(RH)are usually available from weather stations,but the mean radiant temperature(MRT)cannot.The MRT is a key variable in determining outdoor thermal comfort.Therefore,it is necessary to develop a simple and accurate method for calculating MRT,in order to compute the corresponding thermal indices,which can be used to assess the thermal environment more accurately.This study was conducted at a university in Guangzhou,China.Four different ground-cover surfaces(concrete,asphalt,lawn,and granite)were selected for study.The T_(a),black-globe temperature(T_(g)),long-wave(L),and short-wave(K)radiation in six directions,and wind speeds(V_(a))were measured under unshaded conditions.The MRT obtained by the six-direction integral method was used as the base value and regression analyses were performed with Ta,K↓(downward short-wave),and Va.In addition,the six indices—significance(P),linear regression coefficient(R^(2)),consistency index(d),root mean square error(RMSE),mean bias error(MBE),and mean absolute error(MAE)—were used for quantitative analysis to explore the feasibility of this method.This study compared five calculation models on MRT:MRTSDIM(six-direction integral method),MRTBGTM-Va-0.1Hz(black-globe thermometer method,0.1 Hz wind speed measurement frequency),MRTBGTM-Va-10Hz(black-globe thermometer method,10 Hz wind speed measurement frequency),MRTBGTM-P(polynomial regression based on black-globe thermometer method),and MRTSDIM-P(polynomial regression based on six-direction integral method).The MRTSDIM was used as a baseline value,and the values obtained by other four methods were discussed and validated separately.The results show that the calculatio

关 键 词：mean radiant temperature outdoor thermal environment solar radiation ground-cover surface six-direction integral method 

分 类 号：TU111[建筑科学—建筑理论]