System Design And Experiment Of The Thermal Exchanger For Underwater Vehicles

Ocean thermal energy has the characteristics of wide distribution,large storage capacity and long-term stability,which is especially suitable for underwater vehicles with profile movement.The development and application of the thermal exchanger acquisition device,can effectively solve the problem of insufficient energy carried by the submersible itself,improve the endurance capacity,and enhance the ability of human beings to observe the ocean.This paper studies the phase change heat transfer process of thermal exchanger,and the process of obtaining transforming the ocean thermal energy.On this basis,the thermal exchanger is designed and verified by experiments.The main contents of this paper are as follows。(1)Taking concentric circular heat exchanger as the thermal energy acquisition device,a scheme of thermal energy exchanging-power generation system was proposed.According to the requirements of the vertical temperature distribution of the detected target sea area for the thermal and physical properties of the phase change material,the corresponding phase change material is optimized to match the profile movement process of the thermal energy underwater vehicles.(2)In order to improve the heat transfer efficiency of heat exchanger and reduce the waiting time for phase change of thermal energy underwater vehicle,double ring heat conduction fins are designed.The heat conduction fin has the advantages of simple structure,light weight and large heat transfer area,and effectively connects the heat transfer path between the heat source and the central phase change material.(3)To accurately measure the volume change rate of phase-change materials,a testing platform for the volume change rate of phase change materials was designed.The testing platform can measure the volume change rate and work capacity of phase change materials.(4)Taking the heat exchanger with double ring heat conduction fins as the research object,a simplified "C" type two-dimensional phase change heat transfer model was established,and the finite element heat transfer process simulation was carried out to simulate the phase change material phase change process,so as to optimize the distribution of heat conduction fins in the heat exchanger and improve the overall heat transfer efficiency of the heat exchanger.(5)Building the experimental platform of thermal transfer device to carry out heat transfer process experiments.The experimental results show that the heat transfer efficiency can be improved by 9.33 % by using double ring heat conduction fins.At the same time,the pressure test about the work process of the phase change material is carried out,to obtain the curve of the working pressure of the thermal exchanger and the change process of the phase change time,which provides the basis for the design of the thermal energy acquisition device.