Measuring molecular forces with MolFlow+

The source of the molecular force is the impulse change of an incoming molecule on the surface of the facet:

Since the particle undergoes an impulse change, by definition the opposite impulse change is exerted to the facet. Since MolFlow+ simulates a flux of particles (in steady-state), the impulse change rate can be converted to a force:

And, if the user defines a global reference point in the geometry, the torque relative to that point can also be calculated:

To enable measurement (that comes at a ~5% performance impact, and somewhat larger file sizes), and to extract the measured data, see the dedicated page in documentation.

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Last update: January 22, 2024