DIFFUSER HAVING IMPELLER FOR CENTRIFUGAL AND MIXED FLOW PUMP

PURPOSE:To provide a diffuser having an impeller for a centrifugal and mixed flow pump in which two lines of blades are arranged in a radial direction, and matching is obtained between a full pressure loss coefficient and a static pressure recovery coefficient. CONSTITUTION:In a diffuser having an impeller, blades are arranged on a fluid flowing field on an outer periphery of an impeller of a centrifugal or mixed flow pump. Blades 1, 2 of the diffuser are arranged with the same numbers in a circumferential direction while being divided in first and second lines in a radial direction. The chords of the first line blade 1 and the second line blade 2 show dislocation of + or -7.5 deg. in a parallel direction. The rear edge of the first line blade 1 is distanced from the front edge of the second line blade 2 by a distance indicated by DELTAR=0.05 or 0.4L in the radial direction. The first line blade 1 is dislocated from the second line blade 2 by a pitch indicated by DELTAP=0 or 0.4 in a reverse-rotation direction of the impeller. L denotes the length of the chord of the first line blade 1.