축류식 In-line Duct Fan의 유동장 특성에 관한 실험적 연구

초록

Experimental study on the steady/unsteady aerodynamic characteristics of axial type In-line duct fans was conducted to enhance the performance of those axial type In-line duct fans. Flow characteristics at peak efficiency points for two types of In-line duct fans( a single stage fan and a counter-rotating one) were compared with each other. The performance tests were carried out based on the Korean Standard Testing Methods for Turbo-fans and Blowers ( KS B 6311 ). A fivehole probe was used to measure the steady flow fields in the fans. Unsteady flow fields were measured using 45° inclined hot-wires. The magnitude of swirl velocity components at the fan outlet flow of the counter-rotating axial type In-line duct fan was smaller than those at the fan outlet flow of the single-stage In-line duct fan. The results clearly explain the lower pressure loss of the counter-rotating In-line duct fan compared with those of the single stage In-line duct fan.