Construction and preliminary testing of perforated-plate heat exchangers for use in helium IIrefrigerators

✍ Scribed by François Viargues; Gerard Claudet; Peter Seyfert

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 371 KB
• Volume: 34
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/s0011-2275(05)80072-4

✦ Synopsis

Heat exchangers in cryogenic refrigerators must meet conflicting requirements for high thermal efficiency and low frictional pressure drops. This is particularly true in helium II refrigerators where the gas stream leaves the cold source at 15 mbar. Perforated-plate heat exchangers are likely to offer better overall performances for that application than the widely used plate-fin heat exchangers. Through their design they combine a high thermal conductance in transverse direction with a low thermal conductance in axial direction. The present paper reports on the initial stage of development of a fabrication method using photochemical milling of copper plates and stainless steel spacers, and silver brazing for bonding. Comparison of preliminary test measurements and calculations in the 80 to 300 K temperature range with flow rates between 1 and 5 g/s has confirmed that predictable results can be obtained for the thermal efficiency and the pressure drop with an accuracy of a few percent.