Suppression of rotating stalls in the radial vaneless diffuser of a centrifugal fan

摘要

A study was made on the suppression of rotating stall in the radial vaneless diffuser of a centrifugal fan. A plate was attached to the internal wall downstream of the inlet of the diffuser to control periodical fluctuations, which cause rotating stalls, in the ring-shaped reversed flow region. Test results indicated that, insofar as the scale of the present study is concerned, attaching an appropriately sized plate at an appropriate location and having a clearance between this plate and the shroud wall were effective in suppressing rotating stalls.