Hello, A change in allocation has been requested: Requester: wardle (Kent E. Wardle) Project: SepCFD Title: CFD Simulation of Separations Processes Description: This project seeks to apply the open-source CFD package OpenFOAM to simulation of the complex, multiphase flow in liquid-liquid separations devices used for processing nuclear fuel via solvent extraction with a particular focus on simulations of the flow in the annular centrifugal contactor (https://sites.google.com/site/kwardleweb/research/computational/cfd). For such processes, complex physical phenomena including free surface flow and liquid-liquid droplet breakup and coalescence must be incorporated. Accurate simulation of such physics requires fine meshes to resolve phase boundaries as well as efficient computational performance to enable transient simulations spanning several seconds of flow time despite the very small time steps that are required (~10-6 s). The specific simulation techniques to be used for the OpenFOAM simulations are based on the Volume of Fluid (VOF) method with Large Eddy Simulation (LES) of turbulence. Recently, a hybrid multiphas e CFD method which couples multifluid (per-phase momentum equations) with VOF interface sharpening for selected phase interfaces was developed. With this new solver, a three phase system can be modeled enforcing a sharp interface for liquid–air interfaces and at the same time allow interphase dispersion and mixing for the liquid–liquid flow. Local mean droplet size can be predicted using a reduced population balance method and interface sharpening can be switched locally according to comparison of the local drop size and local mesh size. The current focus is on validation of the multiphase solver for a variety of relevant flows. The code package OpenFOAM uses a C++ object-oriented framework with dynamically linked libraries and high-level solvers to enable the user to write custom solvers and combine various physics models and equations enabling the evaluation of unique combinations of models such as are required for the development of advanced liquid-liquid mixing simulation capability as targeted in this work. This allocation supports nuclear fuel cycle simulations efforts under DOE-NE as well as potential collaborations with DOE-EM sites such as Savannah River where centrifugal contactors and other multiphase separators are in use. Current: undetermined amount Justification: Requested: 450000 A specific reason has been given: I believe I had made a request back in Jan/Feb for 725000 and am just now realizing I never heard anything. I have been pulled into experimental work until now and am getting back to the CFD work. In addition, I will have a student working with me this summer, Olabanji Shonibare, and we will need CPU-hours to support his effort as well. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System