among the all parameters affecting the performance of a downhole de-oiling hydrocyclone, the investigation of internal flow field deserves more attempts especially in the petroleum industry. in this study, the effects of inlet flow rate, inlet oil volume fraction, and oil droplet diameter on the separation efficiency and pressure drop ratio have been investigated along the hydrocyclone body. al...

Consider the dynamics of turbulent flow in rivers, estuaries and floods. Based on the widely used k-ǫ model for turbulence, we use the techniques of centre manifold theory to derive dynamical models for the evolution of the water depth and of vertically averaged flow velocity and turbulent parameters. This new model for the shallow water dynamics of turbulent flow: resolves the vertical structu...

We describe the first DNS-based measurement of the complete mean response of a turbulent channel flow to small external disturbances. Space-time impulsive perturbations are applied at one channel wall, and the linear response describes their mean effect on the flow field as a function of spatial and temporal separations. The turbulent response is shown to differ from the response a laminar flow...

In this paper, the turbulent air droplet flow inside a single passage of a curved type vane separator has been studied numerically. The simulation is based on the Eulerian - Lagrangian method. For turbulent air flow calculations, a computer code was developed to solve the Reynolds Averaged Navier Stokes (RANS) equations together with the equations of Reynolds Stress Transport Model (RSTM) o...

The main purpose of this study is to estimate the step heat fluxes applied to the wall of a two-dimensional symmetric channel with turbulent flow. For inverse analysis, conjugate gradient method with adjoint problem is used. In order to calculate the flow field,   two equation model is used. In this study, adjoint problem is developed to conduct an inverse analysis of heat transfer in a channel...

In this paper, the Al2O3-water nanofluid flow in laminar and turbulent flows inside tubes fitted with diamond-shaped turbulators is numerically modeled. The nanofluid flow is modeled by employing a two-phase mixture method and applying the constant heat flux boundary condition at tube walls. In the results, the effects of different parameters such as the geometry of turbulators, volume fraction...

in this study, the turbulent kinetic energy redistribution process is investigated. to this aim, the direct numerical simulation (dns) of incompressible flow of a newtonian fluid through a channel at a shear reynolds number of reτ = 180 is used to produce a flow data base. then, these data are statistically analyzed. the turbulent kinetic energy redistribution is studied using the pressure-stra...

The products of the primary OH-initiated oxidation of toluene were investigated using the turbulent flow chemical ionization mass spectrometry technique at temperatures ranging from 228 to 298 K. A major dienedial-producing pathway was detected for the first time for toluene oxidation, and glyoxal and methylglyoxal were found to be minor primary oxidation products. The results suggest that seco...

The energy gradient theory has been proposed with the aim of better understanding the mechanism of flow transition from laminar flow to turbulent flow. In this theory, it is suggested that the transition to turbulence depends on the relative magnitudes of the energy gradient amplifying the disturbance and the viscous friction damping that disturbance. For a given flow geometry and fluid propert...