NUMERICAL STUDIES ON THE EFFECT OF IMPELLER CONE ANGLE ON AERODYNAMIC PERFORMANCE OF MIXED FLOW COMPRESSORS

摘要

Detailed aerodynamic design of mixed flow impellers with cone angles of 60°, 50° and 45° was carried out based on centrifugal compressor design methodology for given operating conditions. An analytic equation approach was used for generation of blade profiles, resulting in inclined cut impellers with 11 full length and 11 splitter blades. The three impeller builds were numerically analysed at design speed, and their overall performance as well as detailed flow behaviour were examined and compared. At design mass flow rate, the impeller with 6 0° cone angle gave relatively higher efficiency; however the design mass flow rate was not reached for 50° and 45° cone angle impellers. The 50° cone angle impeller gave highest pressure ratio, whereas the 6 0° cone angle impeller exhibited highest stall margin. With better operating range and uniform flow at the impeller exit, the mixed flow impeller of 6 0° cone angle appeared to be better than the 50° and 45° cone angle designs.