주방용 후드 최적의 수평 급기속도 결정에 관한 연구

We have investigated on the determination of an optimal horizontal air jet velocity of a range hood system by using a segregated finite element method to conduct three dimensional numerical simulations. The horizontal air jet plays a role of air curtain to isolate a heat generated by a cooking range. Therefore, it can efficiently pump out the isolated heat and contaminant air preventing them from being convected into a living space. SIMPLE algorithm was employed to find steady solutions for turbulent flows and k-omega two-equation model was used for turbulence modeling. Present numerical simulations show that the air jet of the present range hood system generates coanda effect isolating the contaminated air in a certain region to pump it out whereas the jet pushes back the contaminated air into a living room as its velocity increases more than the optimal one. Therefore, it can be said that the optimal jet velocity is determined by the competition of the those two mechanism. Both streamlines and temperature contours are displayed to demonstate the mechanism for various jet velocities at a given exhausted flow rate of hood. We have found that the optimal jet velocity exists around 5 m/sec for the range hood geometry considered in this study.