Wyniki wyszukiwania - BazTech

1

Application of optimisation method in order to solve inverse design problem of Ship Propulsion System (SPS)

Kucharski T., Wójcik T.

Vibrations in Physical Systems

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2002

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Vol. 20

200--201

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Turbomachinery component design by means of CFD

Braembussche R. A. van den

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2002

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Vol. 6, No 1

39-61

EN

A short overview of the main techniques for turbomachinery blade design based on CFD is followed by a more detailed description on an Optimisation- and Inverse Design method, developed at the von Karman Institute. The optimisation method uses an Artificial Neural Network to extract knowledge from a Database containing the results of previous designs and a Genetic Algorithm to define the optimum blade. The inverse design method makes use of the Euler or Navier-Stokes equations to predict how a given 3D blade shape should be modified to reach a prescribed pressure or Mach number distribution along the blade surface. Examples of transonic compressor and turbine blades, designed by both methods, illustrate the potential of these modern aero-design systems. Special attention is given to the problems related to existence and uniqueness and to those features that facilitate the practical use of these methods.

3

A Novel 3D inverse method for the design of turbomachinery blades in rotational viscous flow: theory and applications

Tiow W. T., Zangeneh M.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2002

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Vol. 6, No 1

63-78

EN

The development and application of a three-dimensional (3D) inverse methodology is presented for the design of turbomachinery blades. The design method is based on the specification of the blade loading distribution and the corresponding blade shape is systematically sought using directly the difference between the target and initial values. The design procedure comprises mainly of a CFD solver code and the blade-update algorithm to calculate the desired blade geometry as well as the corresponding 3D flow. The CFD code is a well-validated three-dimensional flow solver and has shock capturing ability to cope in both subsonic and high transonic-shocked, viscous flow. Fundamentally, it is a cell-vertex, finite volume, time-marching solver employing the multistage Runge-Kutta integrator in conjunction with accelerating techniques (local time stepping and grid sequencing). To account for viscosity, viscous forces are included in the solution using the log-law and mixing length models. The effects of rotating blades as well as tip clearance flow are also included in the flow prediction. The capabilities of the present method are demonstrated in the redesign of a transonic fan blade, the NASA Rotor 67. The redesign focuses on the shocked flow near the tip, where the effects of shock-boundary interaction and leakage flow are examined. The result shows conclusively that the shock-formation and its intensity in such a high-speed turbomachinery flow are well defined on the loading distributions. Simple guidelines to change the loading distribution can be followed using the proposed inverse methodology to improve the blade shape.