Hi Dears. We want to know the total contact force in the X direction for a defined contact area. In one way, we can output CFT1, CFN1, CFS1 of the given contact area. In the other way, we can also sum all the node forces (CNORMF1, CSHEARF1) on the defined contact area. However, the two methods gave very different results. Why?

Abaqus ​​​​​​​