Section author: Christoph Augustin <>

This example demonstrates the passive inflation of a cavity using a time-varying Neumann boundary condition.


This example generates a simple ring or ellipsoidal shell mesh with dimensions comparable to a human LV (or LV short axis slice, in the case of the ring). Examples of the mesh are shown below:





Boundary Conditions

In this example, the bottom surface of the ring or the top surface of the ellipsoid are constrained to lie in the same plane with Dirichlet boundary conditions, and an additional three nodes on the same surface are constrained such that free body rotation and translation is prevented. Two nodes on the x axis are prevented from moving in the y direction, and one node on the y axis is prevented from moving in the x direction, as illustrated for the ring mesh below:


To perform the simulation of passive inflation, a Neumann boundary condition is applied to the endocardial surface, and the pressure enforced there is increased linearly over the duration of the simulation.

Result Visualisation

Use the –visualize option to display the deformations in meshalyzer, or use the –plot option to display the passive pressure-volume relation on a graph.