A semi-analytical solution of the Reynolds equation for hydrodynamic bearings in rotordynamic simulations is investigated, which based on Scaled Boundary Finite Element Method (SBFEM). The numerical efficiency this approach compared to (FEM), considering linear as well higher-order shape functions. It observed that SBFEM requires significantly less computational time than FEM, especially with r...

The governing equation of turbulence, that we are interested in, is the incompressible 2D Navier– Stokes equation under periodic boundary conditions. We are particularly interested in investigating the dynamics of 2D Navier–Stokes equation in the infinite Reynolds number limit and of 2D Euler equation. Our approach is different from many other studies on 2D Navier–Stokes equation in which one s...

in the current study the effect of casimir force and squeezed film damping on the pull-in instability and dynamic behavior of electrostatically actuated nano and micro electromechanical systems is investigated separately. linear elastic membrane theory is used to model the static and dynamic behavior of system for strip, annular and disk geometries. squeezed film damping effect is modeled using...

The combined effects of nanoparticle and magnetic field on the nonlinear Jeffery-Hamel flow are analyzed in the present study. The basic governing equations are solved analytically to nonlinear ordinary differential equation using perturbation method together with a semi-numerical analytical technique called Hermite- Padé approximation. The obtained results are well agreed with that of the Adom...

This paper describes a novel approach in simulating laminar to turbulent transition by using two-equation models. The Total Stresses Limitation(TSL) concept is used to make the two-equation model capable of predicting high Reynolds number transitional ow. To consider the transition triggered by laminar separation at low Reynolds number location, which commonly occurs in high speed ow, a sensor ...

One of the major flow phenomena associated with low Reynolds number flow is the formation of separation bubbles on an airfoil's surface. NACA4415 airfoil is commonly used in wind turbines and UAV applications. The stall characteristics are gradual compared to thin airfoils. The primary criterion set for this work is the capture of laminar separation bubble. Flow is simulated for a Reynolds numb...

The Lattice Boltzmann method, a molecule kinetic-based approach, is presented to solve fluid dynamics. Based on the theory of turbulence and molecule kinetics, an extended Lattice Boltzmann equation is put forward to solve turbulent flow with high Reynolds number, in which sub-grid turbulence model is used to simulate vortex viscosity as well as turbulence relaxation time is introduced to modif...