The Effect Of Fluctuation Characteristics Of Natural Wind On The Indoor Temperature

Natural ventilation technique can make full use of natural resources to improvethe indoor air quality and the indoor thermal environment, which is an energy savingand environmentally friendly passive building technique. Natural wind results fromatmospheric motion, whether whose average wind or fluctuating wind both has wavecharacteristics.To explore the effects of the wave characteristics of natural wind on the indoortemperature field and under the fluctuation characteristics of natural wind condition,the effects of building regenerative on the indoor temperature, Firstly, this papersummarizes the theory of mean characteristics and turbulence characteristics ofnatural wind, and further analyzes the characteristics of natural wind based onmeasured speed data. Secondly, based on Matlab software, the random pulsating windsequence is obtained with WAWS, and the stochastic average wind series is acquiredwith the two-parameter Weibull distribution. Thirdly, a simple single-sided ordouble-sided large opening building model has been created, and based on the finitedifference method, discrete equations of one-dimensional unsteady heat transferequation of this model has been built, combined with natural ventilation rate formula,and with simulated fluctuating and average wind speed series respectively as thedistant stream velocity on opening height, and then the Matlab code program has beendesigned for numerical solution. Finally, those aspects are solved including the change of indoor temperature and the effect of internal and external regeneratorcharacteristics, indoor heat sources and opening area on attenuation coefficient anddelay time of indoor temperature under the two wave wind condition. The mainresearch conclusions are described as follows:(1) In the fluctuating wind and wave average wind conditions, indoortemperature, compared with the outside, has an obvious attenuation and delay andmaintains24-hour period fluctuations. When the average wind velocity is equal, thevibration amplitudes of indoor temperature of two wave airflows are smaller than thatof steady wind speed.(2) When the parameters of exterior and interior regeneratorkeep constant, under the condition of two wave wind, as the average wind velocityincreasing, the attenuation factor of indoor temperature both increases and the delaytime both decreases sharply, at last they both remain steady.(3) Under the same wind condition, the thermal parameters and dimensions of thermal mass have differenteffects on attenuation factor and delay time of indoor temperature differently, whilethe same parameter in different wind conditions also differently affect the attenuationfactor and delay time of indoor temperature.(4) Indoor average temperature is linearto indoor heat sources, but the attenuation factor and delay time of indoor temperaturekeep invariant with the change of heat sources.(5) Under the two wind conditions,with the opening area increasing, the attenuation factor of indoor temperature bothincreases while the delay time both decreases, at the end they also remain unchanged.The above findings will be helpful for the natural ventilation and natural ventilationcoupled regenerative architectural design.