Numerical investigations of performance optimization using variable guide vanes in a multistage compressor of a 6 MW gas turbine engine

Abstract

There is a common requirement in the process, oil, and gas turbine industries for high performance axial flow compressors operating over a wide range of mass flow rate and rotational speed at high efficiency. The trend has been for greater blade loading (pressure rise per stage) and increased efficiency, which are typically achieved through sophisticated, computational fluid dynamics designs. This can, however, lead to other performance compromises, especially for off-design operation where surge margin becomes an important parameter. The objective of this work was to investigate the possibility of using alternative means to gain performance improvements by the intelligent use of variable geometry, which may permit design objectives to be better achieved. Results are presented for an axial flow compressor of a 6 MW industrial gas turbine engine, where a numerical optimization algorithm has been applied to the problem of obtaining optimum performance at design and off-design steady-state operating conditions.