Experimental Study on Air Leakage between Smoke Exhaust Opening and Duct

Abstract

Smoke exhaust fans are selected considering the air leakage of the smoke exhaust system, because the gauge pressure in the system is very low. Air leakage occurs in various parts. The clearance between the smoke exhaust opening and the duct is the leakiest part in the system. In this study, experiments were conducted to clarify the air leakage rate between the smoke exhaust opening and duct at an arbitrary clearance with a hermetic sealing method. The air leakage rate was measured for three clearances with four sealing methods. The results showed that the air leakage rate for unsealed cases can be computed by using an orifice flow model. Air-leakage-rate equations for the sealed cases were obtained from the experimental values.