Dear Dillan, How much additional time do you need between now and March 31? What were the parameters the time needed, e.g., length and cores for a run times number of runs required? Regards, Ray ----------------------------------------- Ray Bair Argonne National Laboratory and the University of Chicago On 1/31/17, 4:59 PM, "[email protected] on behalf of [email protected]" <[email protected] on behalf of [email protected]> wrote: Hello, A change in allocation has been requested: Requester: dshaver (Dillon Shaver) Project: CMFD-RANS Title: Development of Multiphase RANS turbulence models 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 and 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. Current: undetermined amount Justification: Requested: 250000 A specific reason has been given: The required simulations became significantly larger than initially anticipated and the design space has increased. With the success of the two-fluid model in Nek-2P, it is now being used for some limited parametric testing on the helical pipe heat exchanger. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System _______________________________________________ allocations-admins mailing list [email protected] https://lists.lcrc.anl.gov/mailman/listinfo/allocations-admins