Hello, A yearly allocation for the LCRC cluster has been requested with the following updated information: Submitter/PI: Dillon Shaver Project Name: CMFD-RANS Division: NE Project title: Development of Multiphase RANS turbulence models Associated funding: NEAMS LDRD NEUP Other Systems: Mira - shared project has ~25M CPU hours Science: The objective of this project is to develop and implement Unsteady Reynolds Averaged Navier-Stokes (uRANS) turbulence models in the Nek5000/Nek2P CFD code for use in multi-phase flow simulations. Project description: RANS and uRANS turbulence models are necessary for the accurate CFD simulation of flows on large scales, such as nuclear reactor fuel rod bundles and full cores. The current state-of-the art for simulation of boiling flows utilizes the RANS framework. Recently, the k-omega turbulence model has been demonstrated with Nek using a homogeneous equilibrium model of multiphase flow (thanks significantly to LCRC support). The goals of this project will be to further extend that model to more sophisticated formulations of multiphase flow, specifically the two-fluid model available in Nek-2P. This will enable the further development and validation of multi-phase models with Nek and the subsequent simulation of large, complex problems of interest in both science and industry. Additionally support for the development of the k-omega model will include simulations of a twin-jet mixing facility to evluate the model performce in capturing the effects of buoyancy a nd free-shear layers on turbulence. Both of which can play a signficant role in multiphase flows. This project will use the CFD code Nek5000 and its branch, Nek2P. Written in a combination of Fortran and C, Nek has been demonstrated to be a highly scalable code using the MPI library. Nek5000 has a long history of use and development on the LCRC systems. Proposed simulations will include helical pipe heat exchangers, nuclear reactor subchannels, and the turbulent mixing of twin jets. Meshes for these problems range in size from <100K elements to >1M elements. The project is expected to have between 2-4 members. Industry partnership: Project URL: Current FY Hours Used: undetermined amount New FY Requested allocation: 400000 Q1: 100000 Q2: 100000 Q3: 100000 Q4: 100000 Justification: Storage requirements: 1TB Thank You, The LCRC Accounts System