The long-term goal of this research program is to model turbulent flow of a ferrofluid in the presence of a magnetic field, in all situations, including with heat transfer. The goal of this grant is to apply direct numerical simulation (DNS) of turbulent flow of ferrofluids to learn how the physics of turbulent flow is modified by the magnetic field and its interaction with a ferrofluid. The direct numerical simulations will provide complete solutions to study the physics of turbulence including spin and the magnetic field. The work will include the direct numerical simulation of turbulent flow of ferrofluids in homogeneous flow (emphasizing energetics) and channel flow (emphasizing how the flow near a channel wall is modified.). The computation of mean field properties from the results of the direct numerical simulations can also be compared with results from the Reynolds-averaged Navier-Stokes (k-e model) solutions. . Ferrofluids have been suggested as coolants in electrical transformers, because the magnetic convection can aid natural convection. This would result in either increased capacity in existing transformers or reduced cost in new transformers, since they could be made smaller. The benefits are not straightforward, however, because magnetic convection can either enhance or detract from natural convection, depending on the complicated interaction of the temperature and magnetic fields. Thus, improved design skills will be very useful. The proposed work could also provide a basis for cooling objects in space with magnetic convection, when that same equipment is cooled on earth by natural convection. The broader impact of the proposed work is that it both provides an enhanced scientific basis for engineering design of equipment benefiting people and permits the continuation of the Principal Investigators' involvement with undergraduate researchers, especially among under represented minorities.
Funded by Fluid Dynamics and Hydraulics and Particulate and Multiphase Processes Programs.