Flow simulation in channels with distorted geometry using a spectral code with coordinate transformations
Abstract
Turbulence is essentially fourdimensional in character, and requires the corresponding treatment of the wellknown NavierStokes equations. However, this has only been possible over the past twenty years and then by using the largest computers available. Interest is now turning from the initial, mainly smooth channel, simulations to geometries of eventual engineering significance. This paper reports a new code using the spectral methods of Orszag, but also incorporating a novel generalized coordinate transformation approach. Initial predictions for smooth channels agree well with published data. For distorted geometries, the initial velocity field has considerable influence on the success of the simulations. This is accommodated by gradual (step) changes towards the required distortion, so that the initial velocity field for the 'new' geometry is the final field from the previous step. Examples are given of different twodimensional channel geometries achieved, and these include the successful prediction of recirculating flows.
 Publication:

International Journal for Numerical Methods in Fluids
 Pub Date:
 March 1987
 DOI:
 10.1002/fld.1650070307
 Bibcode:
 1987IJNMF...7..277F
 Keywords:

 Channel Flow;
 Computational Fluid Dynamics;
 Coordinate Transformations;
 Flow Geometry;
 Numerical Flow Visualization;
 Computerized Simulation;
 NavierStokes Equation;
 Turbulent Flow;
 Velocity Distribution;
 Vortices;
 Fluid Mechanics and Heat Transfer