Available at: https://digitalcommons.calpoly.edu/theses/689
Date of Award
MS in Aerospace Engineering
The Goldschmied Propulsor concept combines boundary layer suction and boundary layer ingestion to improve propulsive efficiency and reduce drag on an axisymmetric body. This investigation of a Goldschmied Propulsor aimed to determine influential characteristics of the suction slot geometry to aid in better slot geometry design and to decrease the suction flow requirements for maintaining attached flow over the entire model surface. The Propulsor model was 38.5 inches in length with a max diameter of 13.5 inches. Three suction slot geometries were investigated with the addition of aluminum cusps to the slot entrance. The cusps varied in the distance they protruded into the incoming suction flow and in the angle they took from the lip into the suction slot. Wind tunnel testing was completed in the Cal Poly 3ft x 4ft test section of the draw-down tunnel at a Reynolds Number of 2.3x106. Results show that of the three cusp geometries, the smallest Cusp A protruding only 0.05 inches into the suction flow, produced the greatest reductions in pressure drag and total axial force for the fan speeds tested. When compared to the no cusp condition, none of the three cusp geometries produced any significant improvement in total drag or in required suction flow rate.