Turbomachinery and method of manufacturing diffusers therefor

Claim 1

A turbomachine comprising a rotor from which pressurized fluid is discharged at a relatively high velocity, a diffuser in series flow relationship with said rotor, said diffuser including an annular entrance chamber having an inner periphery into which the rotor discharge flows and diffuser channels having generally circular inlets extending from the bottom of said annular chamber, said annular chamber being further characterized by a series of convolute node chambers of increased flow area spaced therearound from which said diffuser inlets extend, said convolute node chambers having upstream wall sections of a U-shaped cross section extending outward from the inner periphery of said chamber in a direction generally parallel to and spaced slightly outwardly with respect to the outer walls of the diffuser inlets and downstream wall sections defining with the circular diffuser inlets scalloped leading edges terminating at points spaced radially outward from the inner periphery of said entrance chambers, whereby there is a preliminary diffusion of the compressed gas as it flows through the annular chamber and the differences in vector magnitude and direction of the gas are minimized.