#Slip length comsol 5.3 software#

You can also increase the relative tolerance of the solver to make solve faster.

For that I usually use direct solver (for robustness). After setting up the physics, make sure that the time-dependent solver runs stably. The moving mesh node (I am not sure which version of Comsol you are using, but this method can be also applied to the newer versions):Дefine a 'prescribed deformation' node for the rotating domain with the prescribed mesh displacement as: DX and DYД¦. This assure the momentum transfer of the fluid due to the moving wall.ДҐ. For the velocity of the moving wall place DXdt and DYdt. Only the walls of the rotating domain need to have a 'moving wall' boundary condition. In the fluid flow node, add a flow continuity option and pick the identity pair. To define the rotation of the inner domain in the Cartesian coordinate, create a new variable for the model component and place the following equationsД¤. This can be done by defining a variable and placing the following equations in it:Д¬hange the value to match the angular rotation of you model but be sure you ramp it up correctly.ДЈ. These formulations are available in the CFD Module, and the L-VEL, algebraic yPlus, k-, and low.

#Slip length comsol 5.3 software#

To define the rotation of the inner domain, you need to define the rotation angle (an) as a function of time. The COMSOL MultiphysicsВ® software offers several different formulations for solving turbulent flow problems: the L-VEL, algebraic yPlus, Spalart-Allmaras, k-, k-, low Reynolds number k-, SST, and v2-f turbulence models. Create the inner and the outer circles and form an assembly with an identity pair typeДў.

To create the 2D rotating geometry, follow these steps:ДЎ. I suggest you work first with a 2D geometry to get a feel on the required modelling parameters and their effect for a more complex 3D systems. out of experience, that might be tricky to solve due to the addition of time-dependent solver. Specifically, we investigate the vortex formation length in the Reynolds number regime 10 to 100 for elliptical bodies of aspect ratio in the range 0.4 to 1.4. Ok so you problem is not only a rotating mixing problem but a two-phase. We examine two dimensional properties of vortex shedding past elliptical cylinders through numerical simulations.