Publications

In deriving automatic numerical opitmization alogorithims for aerodynamic applications, the design parameters are usually chosen to be the unknown airfoil/blade profiles.  However, there are certain advantages in using the pressure/velocity distribution as the design variable in some application; the designed distribution can then be used in 3D inverse design method to generate the actual file shape.  Here, this approach will be addressed.  Two methods are used to parametrize the circulation distribution for compressor blades.  Dawes's code is used to predict the viscous

A methodology for designing pumps to meet multi-objective design criteria is presented. The method combines a 3D inviscid inverse design method with a multi-objective genetic algorithm to design pumps which meet various aerodynamic and geometrical requirements. The parameterization of the blade shape through the blade loading enables 3D optimization with very few design parameters. A generic pump stage is used to demonstrate the proposed methodology. The main design objectives are improving cavitation performance and reducing leading edge sweep.

A fully three dimensional compressible inverse design method for the design of radial and mixed flow machines is described.  In this method the distribution of the circumferentially averaged swirl velocity, or rVθ on the meridional geometry of the impeller is prescribed and corresponding blade shape is computed iteratively.  Two approached are presented for solving the compressible flow problem.  In the approximate approach, the pitchwise variation in density is neglected and as a result the algorithm is simple and efficient.  In the exact approach, the velocites and den

A method is presented for the design of multi-component marine ducted propulsors of arbitrary blade loading operating in axisymmetric shear flow.  An “actuator duct” representation is used, whereby each blade row is assumed to consist of an infinite number of blades of finite axial extent.  Employing a further assumption of inviscid flow and using the Clebsch decomposition of the vorticity, it becomes possible to describe both the propulsor throughflow and bypass flow by partial differential equations in terms of Stokes’ stream function and Clebsch variables.  By modelling th

A methodology is presented for designing waterjet pumps to meet multi-objective design criteria. The method combines a 3D inviscid inverse design method with multi-objective genetic algorithm to design pumps which meet various aerodynamic and geometrical requirements. The parameterization of the blade shape through the blade loading enables 3D optimization with very few design parameters. A generic pump stage is used to demonstrate the proposed methodology. The main design objectives are improving cavitation performance and reducing leading edge sweep.

The development and application of a three-dimensional inverse methodology is presented for the design of turbomachinery blades.  The method is based on the mass-averaged swirl, rVθ distribution and computes the necessary blade changes directly from the discrepancies between the target and initial distributions. The flow solution and blade modification converge simultaneously giving the final blade geometry and the corresponding steady state flow solution.

An inverse design methodology is presented for the design of turbomachinery blades using a cell-vertex finite volume time-marching algorithm in transonic viscous flow.

 

Design of axial turbines, especially LP turbines, poses difficult tradeoffs between requirements of aerodynamic design and structural limitations. In this paper, a methodology is proposed for 3D multi-objective design of axial turbine blades in which a 3D inverse design method is coupled with a multi-objective genetic algorithm. By parameterizing the blade using blade loading parameters, spanwise work distribution and maximum thickness, a large part of the design space can be explored with very few design parameters.

The development and application of a three-dimensional inverse methodology in which the blade geometry is computed on the basis of the specification of static pressure loading distribution is presented. The methodology is based on the intensive use of computational fluid dynamics (CFD) to account for three-dimensional subsonic and transonic viscous flows.