Form 9.B Project Summary
Chron:
971574
Proposal
Number:
06.04-4800
Project Title:
A First-Principles Based High Order
Discontinuous Galerkin Methodology
for Rotorcraft Flowfield Studies
Technical Abstract (Limit 200 words)
A first-principles based high order Discontinuous
Galerkin (DG) methodology for rotorcraft flow field
studies is proposed. A 3rd/5th spatial order compact
DG methodology will be developed. The scheme
developed will be compact, i.e., the cell update
overtime depends only on the information from the
cell and its immediate neighbors. A unique
advantage of the compactness of this method is that
it does not require any special treatment near
boundaries and Chimera intergrid boundaries to
maintain high order accuracy.
The compact DG scheme will be implemented in
conjunction with an innovative selective overset
refinement method. This will ensure that the
rotor-blade tip vortices convect over large
distances without dissipation. Thus, this
methodology strives to achieve the philosophy of
h-p refinement for optimal computational efficiency
in the most practical manner. The compact high
order DG/selective overset refinement will be
implemented in an ENO-based high order 3D,
unsteady, overset NS solver specifically developed
for rotorcraft studies by the Principal Investigator
and the Consultant at Georgia Tech during the
demonstration phase.
The proposed methodology will be validated and
tip-vortex core velocity profiles will be compared
with experiments for a rotor in hover. The
comparative costs (CPU, memory overhead),
robustness of the proposed high order compact DG
method with conventional wide-stencil ENO,
MUSCL schemes will be analyzed. Information
fidelity during intergrid flow-feature transfers in
overset grids will be examined.
In Phase II, the focus will be on porting this
methodology to standard NASA platforms such as
OVERFLOW, and their application to handle
complex issues such as rotor-blade interactional
noise issues, generic rotor craft interactional
problems, and tip shape acoustic characteristics
predictions.
Potential Commercial Applications (Limit 200 words)
The proposed first-principles based efficient
resolution of vorticity-laden flowfield will be
applicable to diverse application such as non-linear
lift systems, high lift systems, and vortex buffeting
in fighter planes. Commercial application to civil
aviations include studies of wing-trailing vortex
dynamics from large aircrafts such as 747's, and
prediction of the life-span of such vortices.
Name and Address of Principal Investigator (Name,
Organization Name, Mail Address, City/State/Zip)
Nathan Hariharan
CFD Research Corporation
215 Wynn Dr.
Huntsville , AL 35805
Name and Address of Offeror (Firm Name, Mail Address,
City/State/Zip)
Andrzej J. Przekwas
CFD Research Corporation
215 Wynn Dr.
Huntsville , AL 35805