University of Cambridge > Department of Engineering > Whittle Lab > Graham Pullan

Turbine Aerodynamic Design

NGV 2 Flow Vis
Severe secondary flow in a low aspect ratio turbine stator (axial view from downstream), from [5].

Constraints often dictate that a turbomachine has to operate in a regime which is far from optimal. Such situations can give rise to highly complex flows which are not well understood and which are away from the aerodynamicist's experience. In this strand of my research, both experimental and computational methods are used to provide understanding so that the designer can know how to "better bend the metal". Examples include highly swept blades [1,2], and very low aspect ratio blades [4,5]. In addition, a challenging area, for both experiments and numerical simulations, is the creation of secondary flow due to the unsteady interaction between neigbouring blade rows [3].

Publications

[1] Pullan, G. and Harvey, N.W. (2007) The influence of sweep on the aerodynamics of axial flow turbines in the endwall region. In: ASME IGTI Turbo Expo - Power for Land, Sea and Air, 14-17 May 2007, Montreal, Canada

[2] Pullan, G. and Harvey, N.W. (2007) The influence of sweep on the aerodynamics of axial flow turbines at mid-span. ASME Transactions, Journal of Turbomachinery, 129 (3). pp. 591-598

[3] Pullan, G. (2006) Secondary flows caused by blade row interaction in a turbine stage. ASME Transactions, Journal of Turbomachinery, 128 (3). pp. 484-491

[4] Pullan, G. and Denton, J.D. and Curtis, E.M. (2006) Improving the performance of a turbine with low aspect ratio stators by aft-loading. ASME Transactions, Journal of Turbomachinery, 128 (3). pp. 492-499

[5] Pullan, G. and Denton, J.D. and Dunkley, M.J. (2003) An experimental and computational study of the formation of a streamwise shed vortex in a turbine stage. ASME Transacations, Journal of Turbomachinery, 125 (2). pp. 291-297.

Other Research at the Whittle Laboratory