Diffuser for a radial compressor and method for determining a narrowest part of the diffuser

摘要

The diffuser of the present invention comprises a plurality of passages which intersect at radially inner ends thereof to define a quasi- vaneless annular inlet for receiving accelerated gases from an impeller of a centrifugal compressor. Each of the passages includes a throat portion having a quadrilateral cross section, including two subtantially parallel linear sidewalls and two substantially arcuate opposing sidewalls, effective for reducing the length of and thereby pressure losses from the annular inlet. The linearity and regularity of the diffuser passages enables the diffuser to be manufactured to close tolerances by electric discharge milling an annular plate utilizing a single tool. This assures uniformity and consistency between diffusers.