The Kapitza Resistance between Cu(Cr) and 4He(3He) Solutions and Applications to Heat Exchangers
Anderson and Johnson1 have measured the Kapitza resistance between liquid 3He and copper for the same copper surface in both the work-hardened and annealed states. Below 0.2°K the Kapitza resistance of work-hardened copper was found to be ten times smaller than that of annealed copper. This result probably explains the high Kapitza resistivities measured in dilution refrigerator heat exchangers compared to previous resistivity measurements on unannealed bulk copper.2 High-surface-area copper heat exchangers are generally sintered together at temperatures high enough to completely anneal copper.
KeywordsHeat Exchanger Copper Alloy Copper Surface Boundary Resistance Dilution Refrigerator
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- 3.P.D. Thatcher, Phys. Rev. 156, 975 (1967); J.K. Wigmore, Phys. Lett. 37A, 293 (1971).Google Scholar
- 4.H. Haug and K. Weiss, presented at the 4th Intern. Cryogenic Engineering Conf. Eindhoven Univ., The Netherlands (to be published).Google Scholar
- 5.W.D. Robertson and R.S. Bray, Precipitation from Solid Solution, American Society of Metals, Cleveland, Ohio (1959), p. 328.Google Scholar