Research On Thermal Characteristic And Condensation Problem Of Radiant Cooling System

In modern society，people paying close attention to security, healthiness and comfort ofbuilt environment and enjoy it. Quality of built environment needs to consume enormousenergy.40percent of building energy consumption is energy consumption of HVAC.Traditional air conditioning system has many disadvantages, for example, wasting energy,pollution of the environment, deteriorating indoor air quality and so on. Therefore, clean,energy-saving and comfortable radiant cooling system has received great attention. Basedon this background, characteristics of radiant cooling system and dew problem have beendiscussed in this paper.First, this article studies heat transfer characteristic of radiant cooling system. Thedifference of heat transfer way between it and traditional air conditioning system is pointedout through analyzing heat transfer of radiant panel. And kinds of factors of affecting radiantpanel temperature and the cooling capacity of this system are achieved. This paper alsoattains two necessary conditions whether dew happens or not and factors of impacting dewphenomenon through analyzing process of drop.On the foundation of theoretical research, the paper studied experimentally on radiantcooling system. It analyses indoor thermal environment in different air conditioning mode,for example, single radiant floor, single radiant ceiling, single radiant wall and radiant floorcombined with fan coil system, including vertical temperature distribution, Leveltemperature distribution and relative humidity. Research on factors of impacting dewphenomenon by providing different cooling water temperatures and fluxes is completed.Then this paper contrasts difference of dew phenomenon between single radiant coolingsystem and combined system, besides, works out convection heat flow and radiation heatflow making use of experimental data.At last, this paper researches on factors impacting thermal comfort, and analyzes them.Afterwards, it estimates thermal comfort through calculating the result of PMV and PPD,then discusses energy conservation of this system because it can realize independenthumidity control, raise supplying water temperature and raise design temperature.