Hello Tomas,

From the manual:

"PFAC

LT.0: PFAC must be an integer, and -PFAC is a load curve ID.

The curve defines the coupling pressure on the y-axis as a

function of the penetration along the x-axis.** See Remark ****6.** See “How to correct leakage.”

**6.** PFAC < 0 for CTYPE = 4, 5, or 6. PFAC < 0 refers to a load curve. This curve

may be constructed with the x-axis as the penetration distance (in absolute

length unit) and the y-axis as the maximum estimated coupling pressure. This

curve requires only 2 points. The first point is (0.0,0.0) because no FSI pressure

applies when no penetration occurs. The x-value for the second point is 10% of

the minimum ALE element width, and the y-value is the to be determined maximum

observable pressure in the ALE domain. To determine this y-value, run

the model once with PFAC = 0.1 (the default). Then, select only the ALE domain

and plot its pressure fringes. Next, step through time to identify the maximum

pressure in the ALE domain, selecting the pressure peaks at or near the FSI surfaces.

This maximum pressure becomes the y-value of the second point."

Ian Do