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AIRFOIL CLOCKING Previous: Introduction   The current work is
based on an extension of an approach developed by Rai and is
discussed in detail by Rai [6] and Rai et al. [7]. The approach
is reviewed in brief here. The flow field is divided into two
basic types of zones. Inner "O" grids are used to resolve the
flowfield near the airfoils. These "O" grids are overlaid on
outer "H" grids which are used to resolve the flowfield in the
passages between airfoils. The "H" grids are allowed to move
relative to one another to simulate the relative motion between
rotors and stators. The thin-layer Navier-Stokes equations are
solved in the inner zones where viscous effects are important.
The Euler equations are used in the outer zones where viscous
effects are weak. The governing equations are cast in the strong
conservation form. A fully implicit, finite-difference method is
used to advance the solution of the governing equations in time.
A Newton-Raphson su