Using Dynamic Meshes Introduction In ANSYS FLUENT the dynamic mesh capability is used to simulate problems with boundary motion, such as check valves. - Simulation Driven.pdf: Download. Capabilities-brochure.pdf - ANSYS 14.0 Capabilities. Ewhore pic pack. An overset mesh typically containing a body of interest such as a boat or a gear is superimposed on a background mesh containing the surrounding geometry and data is interpolated between the two. ![]() Hi, I want to do a simulation for a bileaflet mechanical heart valve. Initially, the geometry has very small gaps like 0.05-0.1 mm in the hinges. The pulsatile fluid flow through the valve and leaflets rotate around their hinges (1DOF). During the backflow the leaflets closes the flow domain and prevent the backflow. The movement of the leaflets are not predefined and they move based on the pulsatile flow. Questions: 1. My question is now: This a mechanical heart valve simulation in which the leaflets rotate about 55 degrees around their hinges to fully close the flow domain. I run the simulation from fully-open position for a while so that the flow gets stable and then the leaflets are allowed to rotate. I have improved the simulation using Dynamic mesh option (smoothing diffusion parameter 1 and 2, layering height ratio and default parameters, and remeshing local cell, face and region remeshing). Now the leaflets rotate up to the last angles and simulation diverges before the leaflets and valve close. The skewness angle is less than 0.65 at the beginning but the mesh cells get compressed and stretched to get skenewss angle of 0.96. How to prevent this much deformation in the mesh? Hi Vishal, The leaflets are moving (known rotation from transient structural coupled with Fluent) from 0 angle to 55 degree. Yes, It seems that remeshing is not doing anything as you see the mesh is streched at the center and compressed between the leaflets. I am using Local Cell, Local Face, Region Face for remeshing methods, Sizing Function is NOT on. I set the Minimum and Maximum Length Scales from the Mesh Scale Info and set the maximum cell skewness and face skewness to 0.85 and size remeshing interval is 1. The highest skewness angle is 0.7 before running and get higher than 0.96 in regions: 1. Mostly between the leaflet tips, 2. Leaflets and wall on both sides. Yes the motion is assigned to the leaflets in transient structural based on a table including time and rotation angle. The reason is just doing the 1-way coupling as an approach for this simulation. We have used dynamic mesh and overset mesh and similar problem occurs when the leaflets is closing. I added body sizing and sphere of influence and increased the quality of the (smaller size) in the region around the leaflets. It means that from inlet to downstream of the leaflets have smaller mesh, and larger mesh elements for the rest of the flow domain (far downstream of the leaflets.
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