Study On The Improvement Of The Thermal Environment In The Radiant Cooling Room

In recent years,radiant air conditioning has been paid more attention and applied because of its more energy-saving,beautiful and comfortable features.However,the ground radiant cooling is limited in its application because of its slow cooling,condensation and large vertical temperature difference of indoor air.Therefore,in order to solve the problem of large vertical air temperature difference in the floor radiant cooling room,this paper proposes a prefabricated trench type radiant panel for cooling,introduces ceiling fan ventilation and side blowing ventilation,and studies the indoor radiant ground temperature,air temperature,non radiant wall temperature,velocity field air distribution,etc.by combining experiment and simulation.In the experiment,14 ℃,16 ℃ and 18 ℃ were selected as the water supply temperature,and each water supply temperature was tested without ventilation,ceiling fan ventilation and side blowing ventilation respectively.The changes of indoor air temperature,radiation ground temperature,non radiation wall temperature and other parameters were observed,and the distribution of indoor velocity field was analyzed by simulation.The results show that the temperature of radiant floor and non radiant wall is improved after ventilation,and the ceiling fan working condition is more effective in improving the surface temperature of the floor,reducing the temperature of people’s activity area and reducing the vertical temperature difference;the vertical temperature difference in the room is reduced from 5 ℃ to 1 ℃ after ventilation,with a decrease of more than 80%,and the indoor thermal environment is greatly improved;the ineffective dispersion of the system Under the same ventilation condition,the heat and effective heat dissipation decrease with the increase of water supply temperature,and when the water supply temperature is the same,the ceiling fan and side blowing ventilation can reduce the ineffective heat dissipation of the system and improve the effective heat dissipation of the system;the indoor radiant surface heat dissipation decreases with the increase of water supply temperature under the same ventilation condition,and when the water supply temperature is the same,the ceiling fan and side blowing ventilation can reduce the ineffective heat dissipation of the system Blowing ventilation can improve the radiant heat,but the increase is small,mainly because although the convective heat transfer increased,but the radiant heat transfer decreased,the overall radiant heat transfer increase is not large.Firstly,the indoor thermal environment based on the experiment is simulated and optimized,and the fitting equation of the indoor wind speed at different height corresponding to the different side air outlet wind speed is put forward,then the physical model of the master bedroom is established.Firstly,the composite system of radiant ground cooling and fresh air is simulated,and it is found that the different layout of the new air outlet has little effect on the indoor thermal environment,However,the temperature near the ground is slightly lower than that of other fresh air outlets,and the vertical temperature difference between the ground and the side is also larger.Increasing the fresh air temperature will increase the temperature of the room,while increasing the air volume(increasing the air speed or the size of the new air outlet)will reduce the temperature of the room and reduce the PMV value around the human body,increase the comfort of the human body,and Through the simulation,it is found that the air temperature should not be too low or the air volume is too large to cause the vertical temperature difference to be too large when blowing the fresh air on the side of the ground.Then,the simulation of the composite system of radiating the ground cooling and the side blowing of the fan coil is carried out,and it is found that with the increase of the air speed of the air outlet,the overall air speed in the room and the air speed around the human body are also increased,and the temperature around the human body is also slightly increased The temperature distribution in horizontal and vertical directions is more uniform.