Study On Energy-saving Optimization Of Radiant Cooling Ceiling System Based On Human Thermal Comfort Characteristics

In order to optimize the comfort and energy saving effect of the radiant cooling ceiling air conditioning system,this paper establishes the human thermal response model of the radiant cooling ceiling air conditioning system based on the measured parameters through the University of California:Berkeley thermal comfort simulation software(ie UCBComfort,the UCB be called for short in the paper),and verifies the reliability of the model.Apply the UCB thermal comfort simulation model to optimize the environmental parameters and system parameters of the radiant cooling ceiling air conditioning system,and simulate the data obtained to determine the upper limit of acceptable indoor ambient temperature and define the comfortable temperature range for the environment with radiant cooling ceiling air conditioning system.Secondly,this paper applies the corresponding environmental parameters and system parameters of the radiant cooling ceiling air conditioning system to the energy consumption simulation,simulates the system energy consumption under all working conditions,analyzes the simulation results under different working conditions,and determines energy efficiency of the radiant cooling ceiling air conditioning system optimized by UCB thermal comfort simulation software.The simulation results in this paper show that after the radiant cooling ceiling is turned on,the overall skin temperature and overall thermal sensation of the subject decrease most significantly at 28 ?.The simulated skin temperature of hand decreases the most in all local skin temperature,and the body parts with the largest thermal sensation decline respectively were the head,hand and forearm at each ambient temperature.The abdomen thermal sensation at 26 ?,30 ?,and the thigh thermal sensation at three ambient temperatures,were closer to thermal neutral than the control group.However,since the thermal sensation value is negative,the thermal sensation simulation value rises instead.After optimizing the radiant cooling ceiling air conditioning system,at 28?,compared to the indoor air relative humidity of 70%,the overall skin temperature of the subject is decreased by 0.35?while the relative humidity is reduced to 50%,and the overall thermal sensation decreased by0.27 scales.When the relative humidity was 50%,the skin temperature of hand decreased the most,while for the local thermal sensation,the hand thermal sensation decrease most significantly when the relative humidity was 65%,60%,55%,but at a relative humidity of 50%,the most significant drop is the head thermal sensation.With the radiant cooling ceiling air conditioning system,on the general trend,when the ambient temperature is high,the reduction to the overall thermal sensation of the subject is more significant with enhancing the cooling effect of the radiant cooling ceiling air conditioning system,by lowering the indoor relative humidity,and optimizing the set temperature of the radiant cooling ceiling surface.The radiantcooling ceiling air conditioning system has a significant effect on the comfort temperature range of the extended subject.With radiant cooling ceiling cooling,the lower the relative humidity of the indoor air,the more adaptable the subject is to the high temperature environment,and the acceptable the higher the upper limit of the temperature range.Compared with the window air conditioner,the radiant cooling ceiling and fan coil air conditioning system have an average energy consumption reduction of 25%,and the energy saving efficiency decreases as the air temperature increases.The study found that under various working conditions,when the indoor ambient temperature is 28.6?,the relative humidity is 55%,and the radiant ceiling cooling surface temperature(ie the ceiling temperature)is 20.2?,the radiant ceiling cooling and fan coil air conditioning system is the most energy efficient under the premise of satisfying the thermal comfort characteristics of the human body.