| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a centrifugal compressor and a turbo refrigerator using the same, operable in a wide flow rate range, without reducing efficiency, even when a flow rate decreases in partial load operation or the like. <P>SOLUTION: The centrifugal compressor 1 includes a diffuser arranged on an outer periphery of a first stage of an impeller and a return flow passage for connecting the diffuser and a rear stage impeller. A plurality of guide vanes arranged in a circumferential direction in the return flow passage are divided into a fixed upstream guide vane and a movable downstream guide vane, and are arranged so that a line of connecting the upstream guide vane rear edge and the downstream guide vane front edge turns in the radial direction in rated operation. In the partial load operation, the downstream guide vane rotates around the rotary shaft, and imparts a prerotation angle to the rear stage impeller. <P>COPYRIGHT: (C)2012,JPO&INPIT |
