Fundamental Research Of A Phase Change Regenerator In The Type Of Falling Film

Today,in view of such a serve energy situation,people began to find new ways to save energy.As a number of advantages,the development of phase change energy storage technology has received increasing attention,but the using of phase change material storage device is effected by low heat transfer coefficient of phase change materials,the effect of cold storage-releasing is not ideal.In order to improve the performance of regenerator,from the regenerator and heat storage materials,the researchers respectively is seeking a breakthrough in two aspects,in order to achieve the promotion and application of the regenerator in daily life.In this paper,the falling film forced convection heat transfer,which is used in the falling film evaporator,and the phase change cool storage technology,are combined to design a falling film type phase change cool storage device.The experimental device and the experimental materials are introduced in detail.Including the temperature change of the regenerator,the change of the heat absorption and desorption power,the change of the convective heat transfer coefficient of the falling film,especially the storage and release characteristics of the regenerator and the recycling performance.In the working temperature range,cold working medium and cold using fluid do not appear phase transition phenomenon.In this study,a mixture of decanoic acid,lauric acid and oleic acid were used as phase change cool storage material.The phase transition temperature of the phase change material is about 20 ℃,which is in accordance with the application requirement.All copper tubes filled with phase change cool storage material arranged in a certain arrangement in the cold storage box,through the support plate for positioning and support.A liquid supply is arranged directly above the copper bundle zone to supply the cold working medium and the cold using medium.The experiment of cold storage and cooling performance of the cold accumulator was carried out under the conditions of different working fluid temperature,flow rate and arrangement.The experimental results show that the storage time of the cold accumulator is variable,and it needs less amount of water.The gravity convection heat transfer process can be supplemented to enhance the storage and cooling process,and no other energy is needed.The discharge law of the cold accumulator can be adjusted according to the flow rate of fluid.The relevant law is generally that when the flow rate is large,the cooling time is short and the outlet temperature is high,the flow rate is small,the cooling time is long and the outlet temperature low.The structure of the cold storage device is simple and the maintenance is convenient.To sum up,the regenerator integrated the phase change cool storage technology and falling film forced convection,its performance is more superior than any other forms of regenerators’ performance,has excellent cold storage and cooling performance and good prospects.