MachLine: A Modern, Subsonic/Supersonic Panel Method
Why a panel method?
Here in the AeroLab, we specialize in low-fidelity, potential-flow-based methods. We have found that we can leverage these to quickly and effectively solve aircraft design and optimization problems.
Panel methods are right up our alley. Based on the Prandtl-Glauert equation, they are orders of magnitude faster than CFD or even Euler codes.
Weaknesses of PAN AIR
PAN AIR was a subsonic/supersonic panel code produced in the 1980s by Boeing. It is still available and in use today. However, when working to predict sonic boom loudness for next-generation commercial aircraft, we found PAN AIR unable to handle the cases we were looking at. Some of the issues we encountered were:
Hard limits on mesh sizes
Archaic user interface and inconvenient mesh generation
Unrealistic flow property fluctuations
Our answer: MachLine
Multi-order Approach to Calculating High-speed Linear Aerodynamics
Unstructured incompressible, compressible subsonic, and supersonic panel method.
Lightning-fast Fortran implementation.
Straightforward user interface.
SLT, VTK, and TRI mesh handling.
Built for data visualization using ParaView.
Running MachLine
An overview for running MachLine and viewing the results in Paraview.
Ongoing Research
We're continually developing MachLine. Here are some of the aspects we're working on:
Automatic wake generation and relaxation (for subsonic and supersonic flows).
Automatic adjoint generation for MDAO.
Quadratic-doublet-linear-source distributions on an unstructured mesh.
Source-free solutions.
This research is currently being funded by the US Air Force and is performed in collaboration with Research in Flight.