The applications of mechanical seals are numerous. The most common sealing systems involve rotating-shaft, elastomer, and flange sealing.

The sealing capability of an elastomeric seal depends upon the contact stresses that develop between the seal and the surfaces with which it comes into contact. Leakage may occur when the pressure differential across the seal exceeds the contact stress.

As a general nonlinear finite element tool, the Ansys Mechanical APDL program can:

All of this information is crucial to understanding how mechanical seal systems are designed, how they operate, and how best to apply them to prevent fluid leakage.

Mechanical APDL's fluid-pressure-penetration capability simulates pressure penetration between contacting surfaces based on the contact status (described in Applying Fluid-Pressure-Penetration Loads in the Contact Technology Guide). The fluid penetration pressure load has a path-dependent nature. The penetrating path can propagate and vary, and is determined iteratively.

At the start of each iteration, the program finds all possible starting points which are exposed to the fluid pressure. Among the starting points, the program then finds fluid-penetrating points where the contact status is open or lost, or where the contact pressure is smaller than the user-defined pressure-penetration criterion.

When a contact-detection point has a contact condition of "penetrating," both it and its nearest neighboring nodes are considered to be starting points that are exposed to the fluid pressure.

The fluid pressure begins to penetrate into the interface between contact and target surfaces from the starting points. The fluid penetration can be cut off when contact between the surfaces is reestablished or when contact pressure is larger than the fluid-penetration criterion.