In ideal flows, walls are taken as streamlines. In many cases, the ideal flow for a particular geometry can be formed such that the desired wall streamlines result from the flow solution. Take for example a line source of strength m that is located a distance h above a wall. For an ideal flow solution, we need to find a way to create a streamline along the wall (shown below on the left). Since we have no streaming flow, we can simulate the effect of the wall by creating a mirrored image, with a source located above and below the wall as shown below on the right. Thus, the resulting streamlines for the solution will create a streamline aligned with the wall and we can just use the upper half of the flow to define velocities. Using the source and its mirror image below, find the pressure distribution on the wall where po is the pressure at the stagnation point. h h -h iy