| 摘要 |
<p>1515729 Centrifugal compressors LENINGRAD POLITEKH INST IM M I KALININA 31 July 1975 32031/75 Heading F 1C In a centrifugal compressor the ratio of the length of each impeller blade 6, 7 along itself between its inlet and outlet ends to the width of the channel between adjacent blades at a position radially midway between the inlet and outlet ends of the blades lies between 3À8 and 5À6, and each blade is shaped so that the angle subtended between the blade and a tangent to a circle concentric with the impeller axis at the point of intersection between the blade and the circle remains constant from the inlet end to a position on the blade radially midway between the inlet and outlet ends and thereafter varies parabolically with respect to the radial distance from the impeller axis. As shown, blades 7 may be shorter than blades 6, the radial distance of their inlet ends from the impeller axis being 1À2-1À3 times that of the inlet ends of blades 6. The diffuser vanes 10 may also be alternately long and short, with similar relative radial positions of their inlet ends. The relative velocity of the flow along the rear surfaces of the blades 6, 7 increases only slightly from the inlet end to the outlet end, which the relative velocity along the rear surfaces of the diffuser vanes 10 (which are similar in shape to the blades 6, 7) remains constant.</p> |
