In 3D analysis, Force and Pressure loads are related to each other. The major difference between force and pressure is how it is applied to the system. You can select either force or pressure as a way to excite or load the model, however, one might be easier to use and more accurate than the other depending on the model. The following video will help you understand the difference between forces and pressures. Hope this will guide you accordingly.
Understanding the Difference Between Forces and Pressures - Lesson 4 - ANSYS Innovation Courses
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