The unstructured Navier-Sokes solver NSU3D has been used to compute flow
over complex aircraft configurations in both cruise and high-lift (take-off, landing)
configurations. These latter configurations involve deployed flaps and hence complex
geometries, for which unstructured mesh techniques are well suited.
Using a grid of approximately 3 million points, the flow over a complete
high-lift configuration has been computed.
The solution as a set of pressure contours is illustrated here.
A very large scale calculation has been performed on an aircraft
with no nacelle - pylon. This grid was obtained by refining a coarser 3 million point grid
generated by VGRIDns, using uniform subdivision of all grid cells into eight finer grid cells.
This grid contained 25 million points and was run on the CRAY T3E
usign up to 1450 processors.
The fine grid is too fine to plot reasonably, so the coarser 3 million
grid is shown below.
A full lift curve was computed on both fine and coarse grid and
wind tunnel data. The comparisons are given in the lift curve and drag polars shown below.
The convergence of the solver on both grids is illustrated in the convergence
plot shown below,
while the scalability of the fine grid solution on the CRAY T3E is show in the final figure.
These computations were performed in Fall 1998
and are summarized in the report:
Large Scale Parallel Unstructured Mesh Computations for 3D High-Lift Analysis