COLD DIFFUSION PUMP
Abstract
A novel vacuum pumping device which employs the combined principles of cryopumping and diffusion pumping is described. Because of the extremely low vapor pressure of its working fluid at cryogenic temperatures, such a cold diffusion pump has the potential of achieving an ultimate vacuum exceeding 10 to the -9th power mm Hg. The operating characteristics of an 8-in. experimental cold diffusion pump were studied. The working fluids used were CO2 and NH3, and the cryosurface temperature was maintained with liquid nitrogen. The results are presented in terms of pumping speeds for various noncondensable gases as a function of injection flow rate, nozzle parameters, and limiting pressures. A theoretical analysis of the experimental results is presented. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1961
- Accession Number
- AD0264848
Entities
People
- E.s.j. Wang
- J.d. Haygood
- J.e. Nichols
Organizations
- Arnold Engineering Development Complex