Effect of ground and ceiling planes on shape of energized wakes

Results are presented from an investigation of the structure of energized wakes in the presence of ground or ceiling planes when powered-lift devices are tested at zero and low wind tunnel velocities. Solutions are presented to indicate how the presence of a nearby ground plane causes the energized wake to constrict less than when in free space. In contrast, another set of solutions indicate that the presence of a ceiling plane enhances wake construction so that the wake width is even smaller than when in free space. Hence, a ground plane tends to reduce the chance for interaction between the wake and the energizing elements, while a nearby ceiling plane tends to increase the likelihood for interference.