Merge pull request #1621 from ArneVoss/feature_free_flying_aircraft

Free-flying aircraft that translates and rotates about the center of gravity (rotating frame + translation)

Author: pcarruscag

Common/src/geometry/CGeometry.cpp

@@ -3510,14 +3510,16 @@ void CGeometry::SetRotationalVelocity(const CConfig *config, bool print) {
   unsigned long iPoint;
   unsigned short iDim;
 
-  su2double RotVel[3] = {0.0,0.0,0.0}, Distance[3] = {0.0,0.0,0.0},
-            Center[3] = {0.0,0.0,0.0}, Omega[3] = {0.0,0.0,0.0};
+  su2double GridVel[3] = {0.0,0.0,0.0}, Distance[3] = {0.0,0.0,0.0},
+            Center[3] = {0.0,0.0,0.0}, Omega[3] = {0.0,0.0,0.0},
+            xDot[3] = {0.0,0.0,0.0};
 
   /*--- Center of rotation & angular velocity vector from config ---*/
 
   for (iDim = 0; iDim < 3; iDim++) {
     Center[iDim] = config->GetMotion_Origin(iDim);
     Omega[iDim]  = config->GetRotation_Rate(iDim)/config->GetOmega_Ref();
+    xDot[iDim] = config->GetTranslation_Rate(iDim)/config->GetVelocity_Ref();
   }
 
   su2double L_Ref = config->GetLength_Ref();
@@ -3529,9 +3531,11 @@ void CGeometry::SetRotationalVelocity(const CConfig *config, bool print) {
     cout << ", " << Center[2] << " )\n";
     cout << " Angular velocity about x, y, z axes: ( " << Omega[0] << ", ";
     cout << Omega[1] << ", " << Omega[2] << " ) rad/s" << endl;
+    cout << " Translational velocity in x, y, z direction: ("
+         << xDot[0] << ", " << xDot[1] << ", " << xDot[2] << ")." << endl;
   }
 
-  /*--- Loop over all nodes and set the rotational velocity ---*/
+  /*--- Loop over all nodes and set the rotational and translational velocity ---*/
 
   for (iPoint = 0; iPoint < nPoint; iPoint++) {
 
@@ -3544,15 +3548,15 @@ void CGeometry::SetRotationalVelocity(const CConfig *config, bool print) {
     for (iDim = 0; iDim < nDim; iDim++)
       Distance[iDim] = (Coord[iDim]-Center[iDim])/L_Ref;
 
-    /*--- Calculate the angular velocity as omega X r ---*/
+    /*--- Calculate the angular velocity as omega X r and add translational velocity ---*/
 
-    RotVel[0] = Omega[1]*(Distance[2]) - Omega[2]*(Distance[1]);
-    RotVel[1] = Omega[2]*(Distance[0]) - Omega[0]*(Distance[2]);
-    RotVel[2] = Omega[0]*(Distance[1]) - Omega[1]*(Distance[0]);
+    GridVel[0] = Omega[1]*(Distance[2]) - Omega[2]*(Distance[1]) + xDot[0];
+    GridVel[1] = Omega[2]*(Distance[0]) - Omega[0]*(Distance[2]) + xDot[1];
+    GridVel[2] = Omega[0]*(Distance[1]) - Omega[1]*(Distance[0]) + xDot[2];
 
     /*--- Store the grid velocity at this node ---*/
 
-    nodes->SetGridVel(iPoint, RotVel);
+    nodes->SetGridVel(iPoint, GridVel);
 
   }
 

TestCases/py_wrapper/translating_NACA0012/config.cfg

@@ -8,9 +8,13 @@ RESTART_SOL= NO
 % FREE-STREAM DEFINITION
 %
 % We are translating the domain instead of having farfield velocity.
-GRID_MOVEMENT= STEADY_TRANSLATION
-MOTION_ORIGIN= ( 0.0, 0.0, 0.0 )
-TRANSLATION_RATE= ( -264.994, -5.78219, 0.0 )
+% Note: The rotating frame is intended for 3D cases. To use the feature in a 2D case,
+% care must be taken with respect to the axes, e.g. to obtain a pitching motion, a 
+% rotation about the z-axis can be used.
+GRID_MOVEMENT= ROTATING_FRAME
+MOTION_ORIGIN= 0.0, 0.0, 0.0
+ROTATION_RATE=  0.0, 0.0, 0.5 
+TRANSLATION_RATE= -264.994, -5.78219, 0.0 
 MACH_NUMBER= 0.0
 FREESTREAM_PRESSURE= 101325.0
 FREESTREAM_TEMPERATURE= 273.15
@@ -68,6 +72,6 @@ CONV_RESIDUAL_MINVAL= -9
 %
 MESH_FILENAME= ../../euler/naca0012/mesh_NACA0012_inv.su2
 MESH_FORMAT= SU2
-SCREEN_OUTPUT= (INNER_ITER, RMS_RES, LIFT, DRAG)
+SCREEN_OUTPUT= (INNER_ITER, RMS_RES, LIFT, DRAG, MOMENT_X, MOMENT_Y, MOMENT_Z)
 HISTORY_OUTPUT= (INNER_ITER, RMS_RES, AERO_COEFF)