Model Validation And Modeling Optimization Of Reciprocation Regenerative Air Heat Recovery

As the development of building energy conservation,methods of building energy efficiency in the field of building ventilation win the attention of people.The heat recovery ventilation technology has been one of the key research content of this direction.On the other hand,the characteristics of phase change material storage capacity and relatively stable thermal conditions have been applied,and achieved satisfactory results in many fields.Phase change ventilation heat recovery system is to apply the phase change energy storage technology to the ventilation system,based on reciprocating ventilation mode.The system makes full use of phase change material storage and heat release performance,to achieve the purpose of heat recovery in ventilation,and finally reduces the building energy consumption.In this study,the phase change ventilation heat recovery system is used as the research object,and the heat transfer characteristics and the factors influencing the final phase change ventilation and heat recovery were explored by means of experiment and simulation.In this paper,the reciprocating ventilation system,which is the basis of the phase change ventilation and heat recovery system,are studied.Taking CO2 as an example,the distribution of indoor pollutants in reciprocating ventilation and mixed ventilation was compared,and the effect of reciprocating ventilation on residential ventilation was analyzed.According to the results,it is believed that reciprocating ventilation is a better way of residential ventilation than mixed ventilation.And then this paper shows the main parts of this study.Firstly the preparatory work before the experiment,such as phase change material selection,phase change ventilator preliminary design.After that comes the simulation part of this study.In this study,the simulation was carried out by Fluent software.The simulation method was introduced at the beginning.The simulations of phase change heat transfer and the sensible heat transfer as control experiment were carried out to compare with the results of experiments in the next parts.In the next part,this paper introduces the experimental part of this study,firstly the experimental process and experimental results of the phase change heat transfer experiment and the sensible heat transfer experiment.And then the simulation results are compared with the experimental results.The results show that the simulation results of sensible heat transfer experiments are in good agreement with the experimental results,but there is a large deviation between the experimental results of phase change heat transfer and the experimental results.After adding the phase transition characteristics of the single unit,it is considered that overcooling,the change of the properties of phase change material and the existence of some leakage phenomena in the experiment are the main factors which result in the difference.After the examination of the sensible heat transfer experiment and the single unit phase change characteristic experiment,to analyze the influencing factors of phase change heat transfer,simulation analysis is used to study the effect of phase change material on the heat transfer effect of phase transition.Finally,the effects of other factors on the ventilation and heat recovery efficiency of reciprocating ventilation was calculated with the example of sensible heat and heat recovery and the heat recovery of phase change ventilation was analyzed.In general,the physical properties of the phase change material have a significant effect on the heat transfer of the phase change material,but for the ventilator,the effect of heat storage on the final ventilation effect is more significant;what's more,shortening the cycle time,reducing the air volume and increasing the inlet and outlet temperature difference improve the overall heat recovery efficiency.