Plane-Parallel Flow

the motion of a liquid or gas parallel to some plane such that at all points on a perpendicular to the plane the velocities of the particles, the pressure, and the other characteristics of the current are identical. Examples of plane-parallel flow include the flow around a wing of infinite span by a stream perpendicular to the span and the flow of water over a straight dam of infinite width. It is much simpler to study a plane-parallel flow than a three-dimensional flow because the quantities characterizing the motion are independent of the coordinate on the perpendicular to the plane of motion. When solving specific technical problems, appropriate corrections are introduced into the results given by the theory of plane-parallel flow.