Performance of a liquid helium centrifugal pump for the TOPAZ superconducting magnet

✍ Scribed by T. Haruyama; T. Mito; A. Yamamoto; Y. Doi; K. Matsumoto; H. Kajiwara

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 341 KB
• Volume: 28
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(88)90100-2

✦ Synopsis

A centrifugal pump used for c~rculatmg hqutd hehum through a large superconducting magnet was tested The performance of the pump was measured during a magnet coohng test The pump operated well wtth atyptcal capacity of 400 dm 3 h -~ (Ap = 0 3 kg cm-2) at 20000 rpm An analys~s of the test results ~s gtven

Keywords hehum, hehum pumps, superconducting magnets

Centrifugal pumps for circulating liquid or supercrltlcal helium have been developed and reported by many authors 1 s This type of pump is one of the major components of large superconducting magnet cooling systems Their excellent stability and reliability are necessary for long-term operation However, comparisons between the theoretical and experimental characteristics of such pumps can be found in only a few papers This may be due to the remarkable differences in fluid characteristics of liquid helium and water For the cryogenic system of the TOPAZ superconduct-Ing magnet at TRISTAN 6 7 a centrifugal pump was originally developed and installed s This pump is used to circulate two-phase low quality helium through the magnet, even if the refrigerator stops as a result of various problems, such as when the turbine trips The TOPAZ magnet requires 80 dm 3 h-1 of forced helium flow as a mlmmum flow at a pressure drop of 0 01 kg cm 2 The pump was designed and built to have a typical capacity of 300 dm ~ h-~ at 0 3 kg cm 2 of the delivery pressure r~se In thin Paper, we describe experimental results and analyses of the TOPAZ centrifugal pump