임펠러 흡입구 간극이 원심형 에어포일 송풍기의 성능에 미치는 영향

Performance tests of an airfoil fan and measurement of flow fields at tile impeller exit are carried out to investigate the effects of tile tip clearance between tile rotor and inlet casing on the impeller performance. The impeller is twelve bladed of NACA 65-810 airfoils and tested with 3 different size of gap; 1, 2, 4 ㎜. The relative decrease of pressure rising performance of the fan is 15 percent for the design flow rate when the gap size is 1 percent of tile impeller diameter. The reduction of performance becomes large as the flow rate increases. The data base obtained in the present study can be used for the design and flow analysis of the airfoil fans.