2134/5881 Duncan Walker Duncan Walker Jon Carrotte Jon Carrotte Jim McGuirk Jim McGuirk Enhanced external aerodynamic performance of a generic combustor using an integrated OGV/prediffuser design technique Loughborough University 2010 untagged Engineering not elsewhere classified 2010-01-28 13:51:07 Conference contribution https://repository.lboro.ac.uk/articles/conference_contribution/Enhanced_external_aerodynamic_performance_of_a_generic_combustor_using_an_integrated_OGV_prediffuser_design_technique/9229991 The paper uses experimental measurements to characterise the extent that improved external aerodynamic performance (reduced total pressure loss, increased flow quality) of a gas-turbine combustion system may be achieved by adopting an integrated OGV/pre-diffuser technique. Two OGV/pre-diffuser combinations were tested. The first is a datum design corresponding to a conventional design approach, where OGV and pre-diffuser are essentially designed in isolation. The second is an 'integrated' design where the OGV blade shape has been modified, following recommendations of earlier CFD work ([14]), to produce a secondary flow/wake structure that allows the pre-diffuser to operate at a higher area ratio without boundary layer separation. This is demonstrated to increase static pressure recovery and reduce dump losses. Experimental measurements are presented on a fully annular rig. Several traverse planes are used to gather 5-hole probe data which allow the flow structure through the OGV, at inlet and exit of the pre-diffuser, and in the inner/outer annulus supply ducts to be examined. Both overall performance measures (loss coefficients) and measures of flow uniformity and quality are used to demonstrate that the integrated design is superior.