A unifying approach for the identification of flow factors contributing to the surface pressure

This research establishes a new methodology, called the pressure partitioning method, to unify different techniques proposed for dissecting the causal effects contributing to pressure on submerged surfaces. Unlike the closely related and popular force partitioning method, which describes the global impact of the flow field, the pressure partitioning method enables the description of the origin of hydrodynamic stress concentrated in a localized region of the body. We will discuss how to use viscous potential auxiliary flow and the reciprocal theorem to divide the pressure force into different contributions related to the added mass effect, vortex effect, bounded vorticity actions, and viscous shear. To enable efficient calculation, the potential field around the submerged body with a localized Dirac-delta flux boundary is solved, and the results from this potential solution will be translated into a viscous potential field. Through this step, we will show how to unify a broad range of apparently different techniques into one procedure. Finally, we will demonstrate the performance of this technique for several canonical problems.