Turbulent flow separation over a wall-mounted hump model and its control using plasma actuators were studied numerically and experimentally. The hump model chosen in this study was that used in a 2004 NASA Langley CFD validation workshop for turbulent separation control using synthetic jets. The numerical simulations solved the Reynoldsaveraged Navier-Stokes equations using Fluent. Different tu...

Turbulent heat transfer in buoyancy-dominated flows is a challenging problem for computational fluid dynamics (CFD). Many authors attribute model error these conditions to the Reynolds analogy. We leverage brand-new direct numerical simulation database evaluate performance of several popular turbulence models buoyant diabatic channel flow. find that results are relatively accurate, with Nusselt...

L-P. Wang Department of Mechanical Engineering, Pennsylvania State University, University Park, Pennsylvania • Dilute, dispersed two-phase flows arise in many contexts ranging from solid particles or droplets in gas flows to bubbles in liquids. Many of the flows of interest are turbulent, which presents a complex problem to analyze or to determine the dominant physical processes contributing to...

Soot volume fraction and number density in a turbulent diffusion flame burning kerosene/air were predicted using two approaches. The first used a conventional soot inception model based on the acetylene concentration and is referred to as the acetylene model. The second used a soot inception model based on the formation rate of three and two ring aromatics [1] and is referred to as the PAH ince...

Velocity increments over a distance r and turbulent energy dissipation on a box of size r are well described by the multifractal models of fully developed turbulence. These quantities and models however, do not involve time-correlations and therefore are not a detailed test of the dynamics of the turbulent cascade. If the time development of the turbulent cascade, in the inertial range, is rela...

It has been shown that fragmentation within self-gravitating, turbulent molecular clouds (‘turbulent fragmentation’) can naturally explain the observed properties of protostellar cores, including the core mass function (CMF). Here, we extend recently developed analytic models for turbulent fragmentation to follow the time-dependent hierarchical fragmentation of selfgravitating cores, until they...

energy equation for turbulent flow in a rotating system was derived in terms of second order correlation tensors, where the correlation tensors were functions of space coordinates, distance between two points and time. to reveal the relationship of turbulent energy between two points, one point was taken as origin of the coordinate system. due to rotation, the coriolis force played an important...