A new type hybrid algorithm using local gridless techniques
Acta Aerodynamica Sinica, 26 (3):
344-348+371 (2008)Abstract
A new type hybrid algorithm using local gridless techniques (HLG)
is developed for the solution of flows over arbitrary configurations.
In this approach, the flow field is basiclly discretked by Cartesian
grids, and local gridless treatment is embedded in the regions adjacent
to bodies. Because of Cartesian mesh's regularity and orthogonality,
it not only provides an efficient mesh generation with simple implementation
of numerical schemes, but also eliminates issues associated with
mesh skewness and distortion, which offers the advantage of shock
capturing with minimal phase error. Furthermore, local gridless techniques
only require a few of points be distributed in the regions adjacent
to the bodies, and so the proposed algorithm with this flexibility
is well suited to arbitrary configurations. Begin with a case of
ideal incompressible flow, the procedure to solve the Laplace equation
as the governing equation is described in details, and the solution
for flows around cylinders in rectangular channel is presented. Then,
the new hybrid algorithm is further developed for solving compressible
Euler equations. Identical problems such as flows across channels
are numerically simulated, and comparison with traditional finite
volume method (FVM) is presented. Good agreement of the captured
shock waves and surface's pressure coefficients is observed, and
the validity of the proposed new method is demonstrated.