Investigation of bladeless fan type air jet thrust systems

This thesis examines 10 bladeless fan models with circular geometries, designed and manufactured with inner diameters of 30 mm, 40 mm, and 50 mm, and slot widths of 0.3 mm, 0.4 mm, 0.5 mm, and 0.7 mm. The study investigated these models through thrust force measurements and flow visualization experiments under varying flow rate conditions. The thrust force measurements were conducted in two stages. In the first stage, thrust forces were recorded at flow rates of 150, 200, 240, 280, 320, 360, 400, and 440 SLPM. In the second stage, measurements were taken at a constant inlet pressure of 2000 mbar. Both sets of results were consistent, showing that thrust force increased as slot width and inner diameter decreased. Flow visualization experiments were carried out at flow rates of 150 SLPM, 300 SLPM, and 450 SLPM. The results indicated that higher exit velocities from the slot increased the volume of air drawn from the fan's front. Additionally, for models with the same slot width, reducing the inner diameter resulted in the flow extending further at a smaller horizontal angle. Similarly, for models with the same inner diameter, increasing the slot width produced comparable effects on flow behavior.