Comfort Study Of Fresh Air Liquid Dehumidification And Radiant Ceiling Air Conditioning System

Fresh air liquid dehumidification and ceiling radiation air-conditioning systemis a new type of air conditioning technology of independent temperature andhumidity control system.It has many advantages in saving air conditioning energy,stabilizing air quality, improving human comfort and the indoor thermal environment,the application prospects of the system is expansive.As an example of an office in Guangzhou,this study establishes physical andmathematical model.The PHOENICS software is used to carry on numericalsimulation to the two kinds of air scheme based on the indoor temperature, relativehumidity, air velocity, LiBr solution ion concentration,the air age and thePMV-PPD.The experiment is done to verify that the established model is correct andthe simulation results are reliable. It analyzes and compares the distribution of indoorsolution Li+concentration in different air supplying and air volume.This paper usesthe PMV-PPD and ADPI index to evaluate the thermal comfort and the two schemesare compared and analyzed to see which is better based on the supply air uniformityairflow, air quality and thermal comfort index.The results show that through the contrastion between measured values andsimulated values, the average error of the temperature and speed control is less than15%, it illustrates the model is correct and the simulation results are reasonable. Theexperimental and simulated both can obtain that the temperature and speed are bothhave good uniformity when the system is running, at the same time thermal comfortand indoor air quality is well.Under the case of unit rated send/exhaustvolume=4000/3200m~3/h,the experimental testing of maximum value of Li+concentration in delivery outlet is0.420μg/m~3.The values of indoor solution Li+concentration in different air supplying and air volume are far less than the standardlimit value of70μg/m~3(The UK Winton Environmental Quality ManagementMonitoring Centre Standards). Under the case of unit rated send/exhaust volume is4000/3200m~3/h and horizontal side sending,when the Li+concentration is70μg/m~3,itcan preliminary estimate by simulating that the range allowed outlets Li+concentration is from100to120μg/m~3.It can conclude initially that it has no harm tohuman health.When tilting upwardly inclined side delivery,the ADPI index is86.6%,the average age of air is about670s, and the PMV-PPD index meets the requirementsthat of-0.5≤PMV≤+0.5and PPD≤10%.