Study On Indoor Thermal Environment Of Buildings In Cold Plateau Area

Due to its special geographical environment and climatic conditions,alpine region is characteristced by strong solar radiation,high atmospheric transparency,and low outdoor air temperature,which leads to indoor thermal environment different from that in the plain area.In addition,the lack of fossil energy in alpine areas makes it more difficult to create a healthy and comfortable indoor thermal environment.At present,domestic and foreign scholars have some research on indoor air temperature,humidity,operating temperature and PMV in the alpine region,but studies on local thermal comfort such as asymmetric radiation temperature and vertical temperature difference are lacking.In this paper,the office building in Lhasa city is taken as the research object,and the indoor temperature,radiation temperature,vertical temperature difference and asymmetric radiation temperature in the alpine region are analyzed by combining experiment and computational fluid dynamics(CFD)simulation,so as to provide a certain research basis for the indoor thermal environment of the alpine region.First of all,the parameters of outdoor air temperature,air humidity,solar radiation and wind speed in Lhasa winter were compered to Chengdu(same latitude)and Beijing(the same climate partition),the results emphasized the climate particularity in high latitude area.Then the influence of the unique climate characteristics in high latitude area on building thermal process was analysised by combining the knowledge of the building environment.Moreover,which provided data support for the CFD simulations.Secondly,the indoor thermal environment of Lhasa was studied by field measurement.The outdoor air temperature and humidity and indoor thermal environment parameters of an office building and a residence.The thermal characteristics constacts of offices with different floors and exterior walls,and residential bedrooms and living room were studied.In addition,the measured data can provide accurate boundary conditions,operating environment parameters for CFD,and verify the correctness of CFD simulation.Subsequently,a physical model was established in Fluent Airpak,boundary conditions were set according to experimental data,Boussinesq(1877)hypothesis was selected,and mass conservation and momentum conservation equations,turbulence model and radiation model were adopted in this model.The indoor thermal environment was simulated and validated by combined with the measured data and local meteorological parameters.Finally,aiming at the coldest day of a typical meteorological year in Lhasa,Beijing in the same climate zone was compared,the indoor thermal environment characteristics of the indoor working hours were analyzed by calculating the vertical temperature difference at different points,local dissatisfaction rate,indoor air temperature and radiation temperature,and asymmetric radiation temperature of human body using the verified CFD model.