Development and Testing of a Miniature Joule-Thomson Refrigerator with Sintered Powder Heat Exchanger
Powder metallurgy technology enables large scale fabrication of low cost miniature recuperative counterflow heat exchangers. The sintered metal powder (SMP) heat exchanger can be a basic component of miniature Joule-Thomson refrigerators. A high pressure gas channel is formed by a capillary tube which is sintered to ball shaped metal grains where the inner grain volume creates a low pressure gas channel. Capillary tube finning and soldering have been eliminated. The supply gas pressure can be as high as the inversion pressure. Cooling power of SMP refrigerators can be 1 W or more. The overall heat transfer coefficients are close to the measured values for Hampson type heat exchangers. SMP refrigerators can be significantly miniaturized in comparison with Hampson ones.
KeywordsHeat Transfer Coefficient Heat Exchanger Coiled Tube Large Scale Fabrication Heat Exchange Area
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