A new multifluid turbulent-mix model
Equations are proposed for a new multifluid turbulent-mix model intended to simulate fluid flows near unstable material interfaces. The model is based on the usual decomposition of the fluid properties into mean and fluctuating parts whose evolution equations are obtained from the Navier-Stokes equations. Correlations among the fluctuating parts produce turbulent contributions to the bulk fluid properties. The innovation is to divide the turbulent contributions into ordered and disordered parts, where the ordered parts are obtained from the average drift motions produced by a set of multifluid interpenetration equations, while the disordered parts are obtained from a set of single-fluid turbulence equations. The problem of dosing the multifluid and single-fluid sets of equations is solved by coupling them together in such a way that they close each other. The resulting energy cascade is from bulk kinetic to ordered drift kinetic to disordered turbulent kinetic to thermal internal energy. The new model exhibits both the early-time convective and the late-time diffusive drift motions seen in numerical and experimental investigations of the evolution of interfacial instabilities. The division of the turbulent contributions into ordered and disordered parts provides a more natural formalism for deriving the equations than has been given for similar mix models that have been proposed. The new model incorporates several simplifying assumptions designed to minimize the extra computational work required, so it is suitable for implementation in multidimensional hydrodynamics codes.
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 465874
- Report Number(s):
- LA-UR-92-2484; ON: DE97003595; TRN: 97:002729
- Resource Relation:
- Other Information: PBD: [1997]
- Country of Publication:
- United States
- Language:
- English
Similar Records
Analysis of turbulent transport and mixing in transitional Rayleigh–Taylor unstable flow using direct numerical simulation data
Analysis of turbulent transport and mixing in transitional Rayleigh–Taylor unstable flow using direct numerical simulation data