Vahid Tavanashad

• PhD in Mechanical Engineering
• AI Frameworks Engineer at Intel

Velocity fluctuations in the carrier phase and dispersed phase of a dispersed multiphase flow are studied using particle-resolved direct numerical simulation. The simulations correspond to a statistically homogeneous problem with an imposed mean pressure gradient and are presented for $\Re_m=20$ and a wide range of dispersed phase volume fractions...

This study provides a detailed account of stochastic approaches that may be utilized in Eulerian-Lagrangian simulations to account for neighbour-induced drag force fluctuations. The frameworks examined here correspond to Langevin equations for the particle position (PL), particle velocity (VL) and fluctuating drag force (FL). Rigorous derivations o...

The hypersonic and supersonic aerodynamics usually involve significant shock-wave boundary layer interaction. This work introduces a specialized force partitioning method to analyze the flow features in shock-wave boundary layer interaction problems over rigid and flexible walls. The pressure force on the wall is partitioned into different componen...

Fully resolved simulation of flows with buoyant particles is a challenging problem since buoyant particles are lighter than the surrounding fluid, and as a result, the two phases are strongly coupled together. In this work, the virtual force stabilization technique introduced by Schwarz et al. [Schwarz, S., Kempe, T., & Fröhlich, J. (2015). A tempo...

The objective of this study is to understand the dynamics of freely evolving particle suspensions over a wide range of particle-to-fluid density ratios. The dynamics of particle suspensions are characterized by the average momentum equation, where the dominant contribution to the average momentum transfer between particles and fluid is the average...

We derive analytical solutions for hydrodynamic sources and sinks to granular temperature in moderately dense suspensions of elastic particles at finite Reynolds numbers. Modelling the neighbour-induced drag disturbances with a Langevin equation allows an exact solution for the joint fluctuating acceleration–velocity distribution function 𝑃(𝑣′,𝑎′;𝑡...

Standard Eulerian–Lagrangian (EL) methods generally employ drag force models that only represent the mean hydrodynamic force acting upon a particle-laden suspension. Consequently, higher-order drag force statistics, arising from neighbor-induced flow perturbations, are not accounted for; this has implications on the predictions for particle velocit...

We derive analytical solutions for hydrodynamic sources and sinks to granular temperature in moderately dense suspensions of elastic particles at finite Reynolds numbers. Modeling the neighbor-induced drag disturbances with a Langevin equation allows an exact solution for the joint fluctuating acceleration-velocity distribution function P(v',a';t)....

Traditional structural health monitoring (SHM) techniques are often based on the assumption that the loading is either absent or can be treated as a stationary random variable. Many of the current SHM methods also necessitate strong actuation or an excessive number of sensors unsuitable for high-speed applications. Here we present an SHM technique...

Standard Eulerian--Lagrangian (EL) methods generally employ drag force models that only represent the mean hydrodynamic force acting upon a particle-laden suspension. Consequently, higher-order drag force statistics, arising from neighbor-induced flow perturbations, are not accounted for; with implications on predictions for particle velocity varia...

In the present work, the collapse of a single non-spherical gas bubble situated above a rigid wall and surrounded by a viscoelastic liquid is studied numerically using the boundary element method (BEM). Assuming that the liquid obeys the "material" Maxwell modelas its constitutive equation, the modified viscous potential theory developed by Lind an...