To simulate a pressurized balloon moving inside a pipe using RecurDyn, a FMBD approach is ideal. This involves modeling the balloon as a deformable body with appropriate material properties and applying internal pressure to simulate inflation. The pipe can be modeled as a rigid body or a flexible body, depending on the desired level of detail.

Defining contact between the balloon and the pipe's inner surface is crucial. This contact interaction will influence the balloon's motion and deformation. By configuring contact parameters like friction coefficient and penetration depth, you can accurately represent the physical behavior.

To capture the influence of the fluid inside the balloon, consider using Fluid-Structure Interaction techniques. This involves coupling the structural analysis of the balloon with a fluid flow simulation. Simplified FSI models or more advanced coupled CFD-FEM simulations can be employed to accurately represent the fluid-structure interaction.

Finally, setting up the simulation involves defining initial conditions, boundary conditions, and solver settings. The initial conditions specify the balloon's initial position, velocity, and deformation. Boundary conditions define the pipe's constraints, such as fixed ends or prescribed displacements. Choosing a suitable solver and adjusting time step size and convergence criteria are essential for accurate and stable results.

Youssouf Belabed Thanks. I really appreciate your suggestions. I just want to know whether for a coupled CFD-FEM simulation, which commercial software is suitable with RecurDyn? Thanks in advance.

Bhushan Dewangan RecurDyn can be coupled with CFD software like OpenFOAM and ANSYS Fluent, the integration with Particleworks is often considered more efficient and robust due to the close collaboration between the two software developers. I personally use ANSYS Fluent but i recommend you use Particleworks.

Youssouf Belabed Thanks for your valuable suggestions.