| 摘要 |
PURPOSE:To optimize the operating conditions of turbine side, by carrying out gas compression in a helium liquefying type refrigerator by means of a radial flow type compressor driven by a gas turbine to change the output pressure of a turbine. CONSTITUTION:A radial flow type compressor 3 in a helium liquefying refrigerator includes a centrifugal type impeller 3a which is directly connected to a gas turbine 7 and which is rotated at a high speed by high pressure neon gas fed from a normal temperature compressor 8. The exhaust port 7a of a turbine 7 is not directly opened to the atmospheric air, and a pressure setting circuit 11 is provided at the outlet of the turbine 7. With this arrangement, the specific speed of the gas turbine 7 may be set within a desired range, 60<=Nst<=150, by changing the output pressure of the turbine. |
