A Three-Dimensional Inviscid Flow Solver in Chimera Flow Simulation.

1994 ◽  
Author(s):  
Y. Wang
Keyword(s):  
Three Dimensional ◽  
Flow Simulation ◽  
Inviscid Flow ◽  
Flow Solver

scholarly journals A Simple Immersed Boundary Method for Compressible Flow Simulation around a Stationary and Moving Sphere

2015 ◽  
Vol 2015 ◽  
pp. 1-17 ◽  
Author(s):  
Yusuke Mizuno ◽  
Shun Takahashi ◽  
Taku Nonomura ◽  
Takayuki Nagata ◽  
Kota Fukuda
Keyword(s):  
Turbulent Flows ◽  
Immersed Boundary Method ◽  
Stokes Equations ◽  
Three Dimensional ◽  
Flow Simulation ◽  
Immersed Boundary ◽  
Hybrid Scheme ◽  
Flow Solver ◽  
Advantages And Disadvantages ◽  
Boundary Method

This study is devoted to investigating a flow around a stationary or moving sphere by using direct numerical simulation with immersed boundary method (IBM) for the three-dimensional compressible Navier-Stokes equations. A hybrid scheme developed to solve both shocks and turbulent flows is employed to solve the flow around a sphere in the equally spaced Cartesian mesh. Drag coefficients of the spheres are compared with reliable values obtained from highly accurate boundary-fitted coordinate (BFC) flow solver to clarify the applicability of the present method. As a result, good agreement was obtained between the present results and those from the BFC flow solver. Moreover, the effectiveness of the hybrid scheme was demonstrated to capture the wake structure of a sphere. Both advantages and disadvantages of the simple IBM were investigated in detail.

scholarly journals The Extension and Application of Three-Dimensional Time Marching Analyses to Incompressible Turbomachinery Flows

1989 ◽  
Author(s):  
P. J. Walker ◽  
W. N. Dawes
Keyword(s):  
Three Dimensional ◽  
Inviscid Flow ◽  
Turbine Rotor ◽  
Navier Stokes ◽  
Flow Solver ◽  
Artificial Compressibility ◽  
Flow Equations ◽  
Long Wavelength ◽  
Time Marching ◽  
Wave Boundary

Conventional time marching flow solvers perform poorly when integrating compressible flow equations at low Mach numbers levels. This is shown to be due to unfavourable interaction between long wavelength errors and the inflow and outflow boundaries. Chorin’s method of artificial compressibility is adopted to extend the range of Denton’s inviscid flow solver and Dawes’ three-dimensional Navier-Stokes solver to zero Mach number flows. The paper makes a new contribution by showing how to systematically choose the artificial acoustic speed to optimize convergence rate with regard to the error wave-boundary interactions. Applications to a turbine rotor and generic water pump geometry are presented.

Transonic and Supersonic Inviscid Flow Equations in 3-D Eccentric Nozzles

2002 ◽  
Author(s):  
Ali Reza Mazaheri ◽  
Homayoon Emdad ◽  
Goodarz Ahmadi
Keyword(s):  
Three Dimensional ◽  
Flow Simulation ◽  
Inviscid Flow ◽  
Analytic Solutions ◽  
Inviscid Flows ◽  
Flow Equations ◽  
The Stability ◽  
The One ◽  
Volume Method ◽  
Steady And Unsteady Flows

Three dimensional unsteady inviscid flows in convergent-divergent nozzles is of importance in understanding the stability of rockets and jet propulsion. A computer program for evaluating unsteady inviscid flow conditions in three-dimensional eccentric as well as concentric nozzles is developed. The program uses the cell-centered finite-volume method based on Roe’s approximate Riemann solver scheme. The flow simulation results in concentric circular nozzles are compared with the one-dimensional analytic solutions and the accuracy of the computation model is verified. The results for steady and unsteady flows through eccentric and concentric convergent-divergent nozzles are then presented. A range of exit to throat areas, pressure ratios, and inlet Mach number are considered.

The Extension and Application of Three-Dimensional Time-Marching Analyses to Incompressible Turbomachinery Flows

1990 ◽  
Vol 112 (3) ◽  
pp. 385-390 ◽  
Author(s):  
P. J. Walker ◽  
W. N. Dawes
Keyword(s):  
Mach Number ◽  
Three Dimensional ◽  
Inviscid Flow ◽  
Turbine Rotor ◽  
Navier Stokes ◽  
Flow Solver ◽  
Flow Equations ◽  
Long Wavelength ◽  
Time Marching ◽  
Wave Boundary

Conventional time-marching flow solvers perform poorly when integrating compressible flow equations at low Mach number levels. This is shown to be due to unfavorable interaction between long-wavelength errors and the inflow and outflow boundaries. Chorin’s method of artificial compressibility is adopted to extend the range of Denton’s inviscid flow solver and Dawes’ three-dimensional Navier–Stokes solver to zero Mach number flows. The paper makes a new contribution by showing how to choose the artificial acoustic speed systematically to optimize convergence rate with regard to the error wave–boundary interactions. Applications to a turbine rotor and generic water pump geometry are presented.

Optimization of the Three-Dimensional Flow Path in the Scroll-Nozzle System of a Radial Inflow Turbine

1984 ◽  
Vol 106 (2) ◽  
pp. 511-515 ◽  
Author(s):  
E. A. Baskharone
Keyword(s):  
Flow Analysis ◽  
Three Dimensional ◽  
Inviscid Flow ◽  
Three Dimensional Flow ◽  
Multiply Connected ◽  
Dimensional Flow ◽  
Nozzle Configuration ◽  
Flow Domain ◽  
Radial Inflow Turbine ◽  
Compressibility Effects

A three-dimensional inviscid flow analysis in the combined scroll-nozzle system of a radial inflow turbine is presented. The coupling of the two turbine components leads to a geometrically complicated, multiply-connected flow domain. Nevertheless, this coupling accounts for the mutual effects of both elements on the three-dimensional flow pattern throughout the entire system. Compressibility effects are treated for an accurate prediction of the nozzle performance. Different geometrical configurations of both the scroll passage and the nozzle region are investigated for optimum performance. The results corresponding to a sample scroll-nozzle configuration are verified by experimental measurements.

Three-dimensional inviscid flow analysis of turbofan forced mixers

1985 ◽  
Author(s):  
T. BARBER ◽  
G. MULLER ◽  
S. RAMSAY ◽  
E. MURMAN
Keyword(s):  
Flow Analysis ◽  
Three Dimensional ◽  
Inviscid Flow

Assessment of Unsteady Flows in Turbines

1992 ◽  
Vol 114 (1) ◽  
pp. 79-90 ◽  
Author(s):  
O. P. Sharma ◽  
G. F. Pickett ◽  
R. H. Ni
Keyword(s):  
Unsteady Flow ◽  
Three Dimensional ◽  
Flow Simulation ◽  
Experimental Investigations ◽  
Flow Parameters ◽  
Research Activities ◽  
Flow Features ◽  
Computational Fluid Dynamics Cfd ◽  
Turbine Design ◽  
The Impact

The impacts of unsteady flow research activities on flow simulation methods used in the turbine design process are assessed. Results from experimental investigations that identify the impact of periodic unsteadiness on the time-averaged flows in turbines and results from numerical simulations obtained by using three-dimensional unsteady Computational Fluid Dynamics (CFD) codes indicate that some of the unsteady flow features can be fairly accurately predicted. Flow parameters that can be modeled with existing steady CFD codes are distinguished from those that require unsteady codes.

Obstacle drag in stratified flow

1990 ◽  
Vol 429 (1876) ◽  
pp. 119-140 ◽  
Keyword(s):  
Experimental Study ◽  
Linear Density ◽  
Three Dimensional ◽  
Inviscid Flow ◽  
Force Balance ◽  
Video Recordings ◽  
Lee Waves ◽  
Time Variations ◽  
Obstacle Height ◽  
Stable Linear

This paper describes an experimental study of the drag of two- and three-dimensional bluff obstacles of various cross-stream shapes when towed through a fluid having a stable, linear density gradient with Brunt-Vaisala frequency, N . Drag measurements were made directly using a force balance, and effects of obstacle blockage ( h / D , where h and D are the obstacle height and the fluid depth, respectively) and Reynolds number were effectively eliminated. It is shown that even in cases where the downstream lee waves and propagating columnar waves are of large amplitude, the variation of drag with the parameter K ( = ND /π U ) is qualitatively close to that implied by linear theories, with drag minima existing at integral values of K . Under certain conditions large, steady, periodic variations in drag occur. Simultaneous drag measurements and video recordings of the wakes show that this unsteadiness is linked directly with time-variations in the lee and columnar wave amplitudes. It is argued that there are, therefore, situations where the inviscid flow is always unsteady even for large times; the consequent implications for atmospheric motions are discussed.

Sign in / Sign up

Export Citation Format

Share Document