Experimental Research And Simulation On Floor Radiant Cooling System

With the increasingly severe energy situation and people's increasing demand for indoor comfort,floor radiant heating system has been more and more widely used.And the floor radiant cooling technology can further improve the suitability and flexibility of the floor radiant system.In this paper,based on a small office building in Shanghai,a composite air conditioning system which combines the floor radiation cooling system with the outdoor air dehumidification system was experimentally studied.The results show that,under the experimental condition,the average indoor temperature of the floor radiant cooling system is about 25.2 ?,and the average relative humidity is about 55.5%.The comfort of the system is good,and there is no condensation.Compared with the fan coil unit system,the indoor temperature of the floor radiant cooling system is more stable.Based on the experimental building,this paper simulates the indoor thermal environment of the floor radiant cooling system,by using Airpak.The simulation results show that compared with the fan coil unit system,the floor radiant cooling system has no local uncomfortable zone,and it has a lower airflow speed and a smaller sense of draft,which means that the floor radiant cooling system is more comfortable.Under the experimental condition,the average PMV of the floor radiant cooling system is-0.34 and the average PPD is 8.84%.And the floor radiant cooling system has the best comfort when the floor surface temperature is 22 ° C.In addition,using Fluent,this paper studies the condensation characteristics of the floor radiant cooling system.The results show that the average temperature of supply and return water,the temperature and relative humidity of the outdoor air,the number of personnel have a significant impact on the floor radiant cooling system's condensation characteristics.When the water temperature is 15 ?,outdoor air temperature is 20 ?,and the number of indoor staff is 2,the maximum relative humidity of outdoor air which can make sure that the system won't condense is 85%.And compared to the mode of top air supply,displacement ventilation can effectively reduce the condensation risk of the floor radiation cooling system.Finally,this paper uses TRNSYS to simulate and optimize the energy consumption of the floor radiant cooling system.By optimizing the supply water temperature,the supply water flow rate,indoor temperature control,and the out air dehumidification system schedule can reduce 56.2% of the energy consumption of the floor radiant cooling system during summer conditions.