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1. |
Finite element technique to solve the elastic strain for Leonov fluid flow |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1059-1072
Gwo‐Geng Lin,
Hsieng‐Cheng Tseng,
Yi‐Shi Ju,
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摘要:
AbstractThe finite element method is used to find the elastic strain (and thus the stress) for given velocity fields of the Leonov model fluid. With a simple linearization technique and the Galerkin formulation, the quasi‐linear coupled first‐order hyperbolic differential equations together with a non‐linear equality constraint are solved over the entire domain based on a weighted residual scheme. The proposed numerical scheme has yielded efficient and accurate convective integrations for both the planar channel and the diverging radial flows for the Leonov model fluid. Only the strain in the inflow plane is required to be prescribed as the boundary conditions. In application, it can be conveniently incorporated in an existing finite element algorithm to simulate the Leonov viscoelastic fluid flow with more complex geometry in which the velocity field is not knowna prioriand an iterative procedure is n
ISSN:0271-2091
DOI:10.1002/fld.1650090902
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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2. |
Assessment of variants of thek–ϵ turbulence model for engine flow applications |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1073-1086
B. Ahmadi‐Befrui,
A. D. Gosman,
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摘要:
AbstractThis paper is concerned with simulation of the mean flow and turbulence evolution in a model engine and comparison of the behaviour of certain important turbulence parameters, namely the intensity, length scale and dissipation time scale, as predicted by three variants of thek–ϵ model developed for application to strongly compressible flows. The predictions pertain to the axisymmetric, disc‐chamber, four‐stroke, Imperial College model engine operating at 200 rpm and compression ratios of 3·5 and 6·7. The paper analyses the predicted variations of these parameters during the induction, compression and expansion strokes and identifies the versions that produce the most consistent and physically plausible variations. The significance, to the turbulence evolution, of the ratio of the turbulence dissipation time scale to the time scale of compression/expansion is also discussed. It is concluded that on these grounds the Morel–Mansour and El Tahry versions are, and the Watkins version is not, suitable for engine ap
ISSN:0271-2091
DOI:10.1002/fld.1650090903
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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3. |
Three‐dimensional reduced Navier–Stokes solutions for subsonic separated and non‐separated flows, using a global pressure relaxation procedure |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1087-1098
R. Cohen,
P. K. Khosla,
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摘要:
AbstractThe reduced Navier–Stokes and thin layer approximations to the Navier–Stokes equations are used to obtain solutions for viscous subsonic three‐dimensional flows. A spatial marching method is combined with a direct sparse matrix solver to obtain successive solutions in a global relaxation process. Results have been obtained for flow fields with and without regions of flow rev
ISSN:0271-2091
DOI:10.1002/fld.1650090904
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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4. |
Second‐order finite difference solutions for the flow between rotating concentric spheres |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1099-1111
Steve Schwengels,
David Schultz,
William Shay,
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摘要:
AbstractThis paper describes a second‐order method to calculate approximate solutions to flow of viscous incompressible fluid between rotating concentric spheres. The governing partial differential equations are presented in the stream–vorticity formulation and are written as a series of second‐order equations. The technique employed makes use of second‐order approximations for all terms in the governing equations and is dependent upon the direction of flow at a given point. This upwind technique has allowed us to generate approximate solutions with larger Reynolds numbers than has generally been possible for second and higher‐order techniques. Solutions have been obtained with Reynolds numbers as large as 3000 and with grids as fine as a 40 × 40 mesh. Results are displayed in the form of level curves for both the stream and vorticity functions. A dimensionless quantity related to the torque acting on both spheres has been calculated from the approximate solution and compared with other results. Results with smaller Reynolds numbers such as 100 and 1000 are in excellent agreement with other publish
ISSN:0271-2091
DOI:10.1002/fld.1650090905
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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5. |
A velocity formulation for flow past a symmetric profile with a wake |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1113-1119
S. M. Räsänen,
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摘要:
AbstractA model having velocity components as basic unknowns is presented for calculation of two‐dimensional flow past a symmetric profile with a wake in a channel. A modified least squares functional is used for the finite element solution of velocities. The determination of the position of the free streamline is treated as an optimum design problem. The concepts of cost function, geometry parameter and sensitivity derivative are employed. Numerical results are compared with published results obtained with streamfunction formulation
ISSN:0271-2091
DOI:10.1002/fld.1650090906
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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6. |
Algebraic turbulence models for the computation of two‐dimensional high‐speed flows using unstructured grids |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1121-1143
Philippe Rostand,
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摘要:
AbstractThe incorporation of algebraic turbulence models in a solver for the 2D compressible Navier–Stokes equations using triangular grids is described. A practical way to use the Cebeci–Smith model and to modify it in separated regions is proposed. The ability of the model to predict high‐speed perfect‐gas boundary layers is investigated from a numerical point
ISSN:0271-2091
DOI:10.1002/fld.1650090907
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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7. |
A fast riemann solver with constant covolume applied to the random choice method |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1145-1164
E. F. Toro,
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摘要:
AbstractThe Riemann problem for the unsteady one‐dimensional Euler equations together with the constant‐covolume equation of state is solved exactly. The solution is then applied to the random choice method to solve the general initial‐boundary value problem for the Euler equations. The iterative procedure to findp*, the pressure between the acoustic waves, involves a single algebraic (non‐linear) equation, all other quantities follow directly throughout thex–tplane, except within rarefaction fans where an extra iterative procedure is required. The solution is validated against existing exact results both directly and in conjunction with the random choi
ISSN:0271-2091
DOI:10.1002/fld.1650090908
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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8. |
Laminar flow and heat transfer over a two‐dimensional triangular step |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1165-1177
S. G. Ravi Kumar,
P. A. Aswatha Narayana,
K. N. Seetharamu,
B. Ramaswamy,
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摘要:
AbstractThe velocity correction algorithm is used in the finite element method to solve forced convection problems between parallel plates with a triangular step, for Reynolds numbers up to 1000. Equal‐order interpolation functions for velocity, pressure and temperature are used. The solutions show a smooth variation of pressure. The streamfunction, isotherms, isobars and velocity profiles are presented for a typical Reynolds number of 500. The skin friction and heat transfer results are presented for Reynolds numbers up to 100
ISSN:0271-2091
DOI:10.1002/fld.1650090909
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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9. |
Conference diary |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page 1179-1182
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ISSN:0271-2091
DOI:10.1002/fld.1650090910
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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10. |
Masthead |
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International Journal for Numerical Methods in Fluids,
Volume 9,
Issue 9,
1989,
Page -
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PDF (102KB)
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ISSN:0271-2091
DOI:10.1002/fld.1650090901
出版商:John Wiley&Sons, Ltd
年代:1989
数据来源: WILEY
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