In the conical annular diffuser of mixed-flow machines a skewed boundary layer develops on the hub wall due to the swirling flow, and flow reversals, which cause poor performance of the diffuser, are liable to occur. An experimental study was carried out to suppress this unfavourable flow by applying low-height guide fences on the diffuser hub wall. Through the application of the guide fences the performance of the diffuser was improved and the optimum number of fences and the best location in the vaneless diffuser was found. Furthermore, the improved understanding of the internal flow structure can be applied to future diffuser design studies.
JansenW.Steady fluid flow in a radial vaneless diffuserTrans. ASME, J. Basic Engng, 1964, 86, 607–619.
2.
JansenW.Rotating stall in a radial vaneless diffuserTrans. ASME, J. Basic Engng, 1964, 86, 750–758.
3.
YoshinagaY.KanekiT.KobayashiH.HoshinoM.A study of performance improvement for high specific speed centrifugal compressors by using diffusers with half guide vanesJ. Fluids Engng, 1987, 109(3), 359–367.
4.
SitaramN.IsaacJ. M.An experimental investigation of a centrifugal compressor with hub vane diffusersProc. Instn Mech. Engrs, Part A, Journal of Power and Energy, 1997, 211(A5), 411–427.
5.
SakaiT.SanbeM.NakayamaT.Experimental study on diffusers for mixed-flow machinesTrans. ASME, J Power, 1979, 281–289.
6.
WiesnerF. J.A review of slip factors for centrifugal compressorsTrans. ASME, Ser. A, 1967, 89, 558.
