Aerodynamic Optimisation of High Pressure Turbines for Lean-Burn Combustion System

Modern lean-burn combustors make use of high flow swirl to maintain flame stability. The swirling flow can persist downstream of the turbine first vane, changing the loading on the rotor, leading to a reduction in efficiency. This paper presents the results of an automatic optimisation study carried out to mitigate the effect of high swirling flow on a high pressure turbine stage. A high-fidelity CFD-based design optimisation using a multi-point approximation (response surface) method is carried-out to produce a new vane and a new rotor configuration with a significantly improved aerodynamic performance. It is demonstrated that the novel optimisation methodology can cope well with a number of near equality constraints needed for a practical design.Copyright © 2012 by Rolls-Royce plc