Element Analysis Of Fluid Flow Research Articles

Finite Element Analysis of Fluid Flow through the Screen Embedded between Parallel Plates with High Reynolds Numbers

This paper provides numerical estimation of Newtonian fluid flow past through rectangular channel fixed with screen movable from 10° to 45° by increasing the Reynolds number from 1000 to 10,000. The two-dimensional incompressible Navier Stokes equations are worked out making use of the popular software COMSOL MultiPhysics version 5.4 which implements the Galerkin’s least square scheme to discretize the governing set of equations into algebraic form. In addition, the screen boundary condition with resistance coefficient (2.2) along with resistance coefficient 0.78 is implemented along with slip boundary conditions applied on the wall. We engaged to find and observe the relationship between the optimum velocity, drag force applied by the screen, and pressure occurred in the channel with increasing Reynolds number. Because of the linear relationship between the optimum velocities and the Reynolds number, applying the linear regression method, we will estimate the linear equation so that future prediction and judgment can be done. The validity of results is doing with the asymptomatic solution for stream-wise velocity at the outlet of the channel with screens available in the literature. A nondimensional quantity, i.e., ratio from local to global Reynolds number Re x / Re , is introduced which found stable and varies from -0.5 to 0.5 for the whole problem. Thus, we are in the position to express the general pattern of the velocity of the particles as well as the pressure on the line passing through the middle of the channel and depart some final conclusion at the end.

A new VOF‐based numerical scheme for the simulation of fluid flow with free surface. Part II: application to the cavity filling and sloshing problems

AbstractFinite element analysis of fluid flow with moving free surface has been performed in 2‐D and 3‐D. The new VOF‐based numerical algorithm that has been proposed by the present authors (Int. J. Numer. Meth. Fluids, submitted) was applied to several 2‐D and 3‐D free surface flow problems. The proposed free surface tracking scheme is based on two numerical tools; the orientation vector to represent the free surface orientation in each cell and the baby‐cell to determine the fluid volume flux at each cell boundary. The proposed numerical algorithm has been applied to 2‐D and 3‐D cavity filling and sloshing problems in order to demonstrate the versatility and effectiveness of the scheme. The proposed numerical algorithm resolved successfully the free surfaces interacting with each other. The simulated results demonstrated applicability of the proposed numerical algorithm to the practical problems of large free surface motion. It has been also demonstrated that the proposed free surface tracking scheme can be easily implemented in any irregular non‐uniform grid systems and can be extended to 3‐D free surface flow problems without additional efforts. Copyright © 2003 John Wiley & Sons, Ltd.

Finite element analysis of fluid flows with moving boundary

The objective of the present study is to analyze the fluid flow with moving boundary using a finite element method. The algorithm uses a fractional step approach that can be used to solve low-speed flow with large density changes due to intense temperature gradients. The explicit Lax-Wendroff scheme is applied to nonlinear convective terms in the momentum equations to prevent checkerboard pressure oscillations. The ALE (Arbitrary Lagrangian Eulerian) method is adopted for moving grids. The numerical algorithm in the present study is validated for two-dimensional unsteady flow in a driven cavity and a natural convection problem. To extend the present numerical method to engine simulations, a piston-driven intake flow with moving boundary is also simulated. The density, temperature and axial velocity profiles are calculated for the three-dimensional unsteady piston-driven intake flow with density changes due to high inlet fluid temperatures using the present algorithm. The calculated results are in good agreement with other numerical and experimental ones.

On finite element analysis of fluid flows fully coupled with structural interactions

The solution of fluid flows, modeled using the Navier-Stokes or Euler equations, fully coupled with structures/solids is considered. Simultaneous and parti- tioned solution procedures, used in the solution of the coupled equations, are briefly discussed, and advantages and disadvantages of their use are mentioned. In addi- tion, a simplified stability analysis of the interface equa- tions is presented, and unconditional stability for certain choices of time integration schemes is shown. Further- more, the long-term dynamic stability of fluid-structure interaction systems is assessed by the use of Lyapunov characteristic exponents, which allow differentiating be- tween a chaotic and a regular system behavior. Some state-of-the-art numerical solutions are also presented to indicate the type of problems that can now be solved us- ing currently available techniques.

Finite element analysis of fluid flows fully coupled with structural interactions

Some advances in capabilities for analysis of fluid flows fully coupled with structural interactions are presented. Incompressible Navier–Stokes and compressible Navier–Stokes or Euler fluids and the full interaction with structures undergoing large deformations, nonlinear material response and contact conditions can be considered. The analysis capabilities are available in the ADINA System, and are integrated within computer-aided design using the available ADINA modeler and CAD interfaces. Various analysis cases are presented to illustrate the solution capabilities.

On finite element analysis of fluid flow in ducts with boundary layer correction

A finite element analysis of fluid flow in ducts is demonstrated. The fluid is assumed incompressible and, except in the boundary layer, inviscid. The finite element program ADINAT is used to solve the potential flow portion of the analysis, and a boundary layer calculation method is employed to correct for the viscous boundary layer effects. This procedure is employed to analyze two simple problems. First, a nozzle passage from a steam turbine is considered. The results of the analysis are compared to another solution obtained using finite differences. The flow in a wind tunnel constructed at MIT is then analyzed, and the results are compared to test data.

Finite element analysis of flow over a weir

The present paper deals with finite element analysis of fluid flow over a weir under gravity. The problem is formulated mathematically as a 2-dimensional nonlinear boundary value problem in terms of a stream function, assuming the fluid to be inviscid and incompressible, and the flow to be irrotational. The problem thus defined is analysed by the use of the finite element method based on a variational principle for a flow with a free surface boundary. Due to the strong nonlinearity of the problem, an iterative procedure based on Newton-Raphson method is employed. Numerical results obtained by the present method are compared with the experimental data. The agreements of these two are quite satisfactory