CFD Modeling of Miscible Fluid Blending in Pulse Jet Mixing Vessels
Pulse Jet Mixing (PJM) vessels will be used in the waste treatment and immobilization plant (WTP)
being built by the Department of Energy at the Hanford site in order to immobilize nearly 50 million
gallons of radioactive waste currently stored in underground tanks well past their initially intended
design life. Although a large majority of the WTP PJM vessels contain suspended solid waste particles,
there are many vessels that are classified as purely single phase. Given its accepted level of maturity,
single phase computational fluid dynamics (CFD) will be investigated in its ability to model the flow in
WTP PJM vessels that can be classified as single phase vessels. CFD based modeling of PJM vessels is
challenging due to intrinsically turbulent flows produced by submerged jets that turn into radial wall
jets after impinging the vessel bottom, and finally converging near the vessel center to form a central
upwash responsible for mixing at the macro scale. Complex vessel internals further add to the CFD
modeling challenges. Lab-scale testing of a prototypic WTP PJM vessel is performed to obtain accurate
experimental datasets that will be used to assess the feasibility of the CFD model to accurately predict
blending of miscible fluids in WTP PJM vessels which is one of the primary mixing requirements for these
subset of WTP PJM vessels that are amenable to analysis by single phase CFD modeling.