Numerical Modeling of Vertical Buoyant Jets Subjected to Lateral Confinement

摘要

The near-field flow and mixing properties of vertical buoyant jets subjected to lateral confinement are studied numerically for different cases, including different confinement indexes and jet densimetric Froude numbers. The performances of different turbulence models are investigated, such as the standard k-epsilon turbulence model and buoyancy-modified k-epsilon model. The modeled results are compared to previous and present experimental observations. The present paper confirms that the universally accepted model (k-epsilon turbulence model) can be satisfactorily accurate, eliminating the need for an advanced modeling approach, as long as suitable modifications are performed. In contrast to previous studies, which used one single and constant value of P-tr and Pr numbers, the present study links these two numbers to the F number, which is more practical and can produce very good results. This study also makes it possible to roughly quantify the rate at which the jet concentration spread width grows and identify the location where impingement occurs, which enables engineers or researchers to perform a quick estimation of the evolution and profile of a laterally confined vertical buoyant jet. (C) 2017 American Society of Civil Engineers.