My CFD archive

I decided to run a wind turbine simulation on OpenFOAM. This is an Arbitrary Mesh Interface setup, run using pimpleDyMFoam. The turbine stem/post has been neglected in the study, in order to ease the simulation process. Wall function was operated on a coarse mesh, which was created using the snappyHexMesh tool and the total number of cells worked up to 3,05,294.  A close eye has to be kept on the usage of the wall function while performing the grid study. Because drastically refining the cells, without creating boundary layers, can cause the Courant number to shoot up while performing the simulation. Three cylindrical geometries were used in the mesh. A small cylinder to house the wind turbine and to form the AMI interface with the intermediate cylinder. A large cylinder to envelop the entire fluid domain. Figure No.1: Pressure Side Figure No.2: Suction Side Below are some of the animations compiled from the simulation.  Velocity distribution alo...

In this section I will address how to use the snappyHexMesh tool to mesh a Cylinder. We can either create an stl file for the cylinder - place it inside the  triSurface/constant  folder and call the same into the background mesh, or a simple cylinder can be directly created by using the 'searchable cylinder' parameter within the snappyHexMeshDict.  cylinder     { type searchableCylinder;   point1 (0 0.0 -0.5);  point2    (0 0.0 0.5); radius 0.01585;     } A refined mesh can be viewed below. The radius of the cylinder is of the order e-02 which gives us some insight into what the cell size for the back ground mesh can be. The blockMesh for the background mesh will be addressed later. Next in line in the snappyHexMeshDict is the Refinement box parameter. This box defines how refinement around the cylinder and importantly how the wake refinement can be achieved. The refinement box separates the finer ref...

I pursued a brief Internship at the National University of Singapore, where a professor introduced me to the subject Aero-elasticity, and as a part of my work I studied Unsteady aerodynamics and the Flutter problem. During my internship time, I performed a very basic pitch & plunge aerofoil simulation, the likeness of which is very similar to that of the 'wing motion' tutorial case found in the openFoam. The idea was to study the separation regions and the force Coefficients.                   The above equation is represented in the dynamicMeshDict with constraints for pitch along y-axis and plunge about z-axis. Figure 1: Evolution of Coefficient of oscillating Drag  Figure 2: Evolution of Coefficient of oscillating Lift                                       Figure 3: Separation Bubble     ...