Daniel Livescu

Learn More
The growth of the two-dimensional single-mode Rayleigh-Taylor instability (RTI) at low Atwood number (A=0.04) is investigated using Direct Numerical Simulations. The main result of the paper is that, at long times and sufficiently high Reynolds numbers, the bubble acceleration becomes stationary, indicating mean quadratic growth. This is contrary to the(More)
We have recently developed a general-purpose non linear system solver environment for complex physics computations on unstructured grids. This environment, named CartaBlanca, was described at last year's Java Grande Forum. CartaBlanca employs a finite-volume method, [1]. The solution of the non linear algebraic systems, arising from representing the(More)
The structure of homogeneous turbulent shear flow is studied using data generated by Direct Numerical Simulations (DNS) and a linear analysis for both compressible and incompressible cases. At large values of the mean shear rate, the Rapid Distortion Theory (RDT) limit is approached. Analytical solutions are found for the inviscid compressible RDT equations(More)
Direct numerical simulations ~DNS! are conducted to study the turbulence-chemical reaction interactions in homogeneous decaying compressible fluid flows. The reaction is of a single-step irreversible Arrhenius type. The results indicate that the heat of reaction has a noticeable influence on the solenoidal and the dilatational turbulent motions. The effect(More)
  • D Livescu
  • Philosophical transactions. Series A…
  • 2013
A tentative review is presented of various approaches for numerical simulations of two-fluid gaseous mixtures at high density ratios, as they have been applied to the Rayleigh-Taylor instability (RTI). Systems exhibiting such RTI behaviour extend from atomistic sizes to scales where the continuum approximation becomes valid. Each level of description can(More)
This paper compares the effectiveness of various multi-resolution geometric representation methods, such as B-spline, Daubechies, Coiflet and Dual-tree wavelets, curvelets and surfacelets, to capture the structure of fully developed turbulence using a truncated set of coefficients. The turbulence dataset is obtained from a Direct Numerical Simulation of(More)
We demonstrate, in the context of implicit-filtering large eddy simulations (LESs) of geostrophic turbulence, that while the attractor of a well-resolved statistically stationary turbulent flow can be reached in a coarsely resolved LES that is forced by the subgrid scale (SGS) terms diagnosed from the well-resolved computation, the attractor is generically(More)