In a number of chemical and nuclear engineering applications, a cover gas is maintained above a liquid pool. In a fast breeder reactor (FBR), argon gas is maintained above the sodium pools to ensure no direct contact between air and liquid sodium. Nevertheless, argon entrains into sodium by a variety of mechanisms, which is detrimental to the reactivity of the core. Furthermore, a large number of components that remain partially submerged in the liquid pool, aid in this undesirable gas entrainment process. The present study numerically explores liquid fall induced gas entrainment in an FBR hot pool. A passive strategy to mitigate gas entrainment is suggested in the form of a circumferential baffle plate. An optimal design for the baffle is achieved through systematic Computational Fluid Dynamic (CFD) simulations. © 2013 Elsevier Ltd. All rights reserved.