Dynamic Heat Transfer Analysis Of Double-cold-source Sample Chamber In Pulsed High Magnetic Field Device And Experimental Investigation

Pulsed High Magnetic Field Device is important to science research on extreme condition, and the cryogenic system,the important part, is the precondition and guarantee for the operation of this device,including the cryogenic system of cooling magnet and cooling sample chamber.The necessity of building Pulsed High Magnetic Field Device is analyzed. The cryogenic system is expatiated, including the designs of magnet and sample chamber's cooling system. The structures of two devices are designed.Cooling the sample chamber is necessary to accomplish and keep the cryogenic state of the sample. The cooling process of the sample chamber is researched. According to the theory of heat transfer, the process of cooling the sample chamber is analyzed and simplified, the mathematical model of two-dimension unsteady heat transfer is established and numerically simulated.The temperature distribution of the bottom and the temperature variation curve of the sample chamber are obtained.The calculation results indicate that the final temperature of the bottom can reach 6.27K after 2h.The capability of the GM refrigerator is tested by experiment, and the temperature variation curves of the first and second stages on the GM refrigerator at no-load and load are surveyed. The temperature variation process of the sample chamber is tested by experiment. Defects in the structure of the device are discovered, and the cooling temperature of the sample chamber is received. The mathematical model's rationality is validated by comparing the results of the simulation and the experiment. The research results are propitious to the optimum design of the device's structure.