Study On The Performance Of Composite Phase Change Material

Phase change material(PCM)is a kind of heat storage material with broad application prospect.However,the thermal conductivity is small,limiting its application areas.In this paper,phase change heat storage materials with different compositions were prepared by using graphite,expanded graphite,graphene and grapheme/copper as additives.The properties of different composite phase change heat storage materials were tested.Test results show that the density decreased,the volume expansion coefficient decreased,the phase transition temperature decreased,the latent heat of phase change decreased and the thermal conductivity increased after adding heat conduction in PCM.For the same kind of thermal conductivity medium,the performance of composite phase change heat storage material with different mass content is tested.The change of the content of the same kind of heat transfer medium leads to the change of the performance of the composite phase change heat storage material.For example,the composite phase change heat storage material prepared by adding graphene and PCM has a decreasing trend with the increase of graphene content,and the volume expansion coefficient has no specific law,and the thermal conductivity increases.In this paper,the performance of the composite phase change heat storage material is obtained by the study of the performance of the composite phase change heat storage material,and the thermal mechanism of the heat storage material is revealed,which provides a theoretical reference for the temperature control of the device.In order to improve the thermal insulation performance of the precision measuring device and reduce the influence of the temperature change on the test precision.In this paper,ANSYS software is used to simulate the thermal transformation process of the precision device during the testing process.The results show that the thermal insulation has a hindrance to the movement of heat,so that the rate of change of the temperature inside the device is slow.However,the temperature inside and outside the device quickly reached a consensus in a short time.The actual test results prove this simulation conclusion.Based on the performance characteristics of the composite phase change heat storage material,the temperature control of the precision device is carried out by using the composite phase change heat storage material with high thermal conductivity.In the-40?60 ? temperature standard,the temperature difference of device is tested.The test results show that the maximum temperature difference of the devices is 28 ?,which is 28%of the external temperature difference.The temperature change rate is slow and the maximum temperature change rate is 4.77?/h,while the external temperature change rate is 60?/h.The heat storage performance of the device after adding the composite phase change heat storage material is improved,the temperature inside the device changes slowly and the temperature difference is far less than the external temperature difference.