The forceCoeffs
function object generates aerodynamic force and moment coefficient data for surfaces and porous regions, with optional:
Basic operation of the forceCoeffs
function object comprises:
forceCoeffs1 { type forceCoeffs; libs ("libforces.so"); patches (<list of patch names>); }
For more complete control, the full set of input entries includes:
forceCoeffs1 { // Mandatory entries type forceCoeffs; libs ("libforces.so"); patches (<list of patch names>); // Optional entries // Field names p p; U U; rho rho; // Reference pressure [Pa] pRef 0; // Include porosity effects? porosity no; // Store and write volume field representations of forces and moments writeFields yes; // Centre of rotation for moment calculations CofR (0 0 0); // Lift direction liftDir (0 0 1); // Drag direction dragDir (1 0 0); // Pitch axis pitchAxis (0 1 0); // Freestream velocity magnitude [m/s] magUInf 30; // Reference length [m] lRef 1; // Reference area [m2] Aref 1.75; // Spatial data binning // - extents given by the bounds of the input geometry binData { nBin 20; direction (1 0 0); cumulative yes; } }
Default behaviour assumes that the case is compressible. For incompressible cases, i.e. solved using the kinematic pressure:
\[ p_k = \frac{p}{\rho} \qquad [\mathrm{m}^2 \mathrm{s}^{-2}]\]
the rho
entry can be used to set the freestream density:
rho rhoInf; rhoInf 100000;
Fields
forceCoeff
momentCoeff
Storing of integrated values for further post-processing:
Cm
Cd
Cl
Cl(f)
Cl(r)
Related:
Source code:
Example usage:
nacaAirfoil
tutorial: $FOAM_TUTORIALS/compressible/sonicFoam/RAS/nacaAirfoilWould you like to suggest an improvement to this page? | Create an issue |
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