Design and Development of a Ground Effects Machine Using Recirculation

The application of flow recirculation is a promising means of improving the efficiency of ground effect machines. The mechanical complexity and ingestion problem characteristic of other recirculation schemes are avoided in the present concept through the use of ejectors.

A simple viscous theory for the internal flow of straight and recirculating ejectors is developed. An additional theory describes the external flow and “closes the loop.” Full scale, two dimensional tests plus three dimensional wind tunnel tests substantiate the analytical work and prove feasibility of the concept. Experimental ejector efficiencies sufficiently high to warrant continued optimism in the system were obtained.