Abstract
A set of two model equations for a multiphase flow is chosen to investigate the influence of approximation formulas. The approximations have been applied to the prediction of Peclet numbers using control volume interface values, as well as for gradient terms occurring as source terms. Use of an exponential approximation for a gradient source term, instead of the conventional central-difference approximation, leads to a remarkable reduction in the number of control volumes required. Different approximation formulas for the predictions of the grid Peclet number are found to have little influence on results. The form of the model equation has also been investigated. The source terms in gradient form in the model have been combined with the convection and diffusion terms to become part of the discretization scheme.
Similar content being viewed by others
Abbreviations
- a :
-
coefficient
- b :
-
coefficient
- C :
-
constant
- D :
-
coefficient for diffusion
- F :
-
coefficient for convection
- H :
-
source term
- ITER :
-
number of iteration
- L :
-
length
- m :
-
number of control volume (for continuity)
- n :
-
number of control volume (for momentum)
- U :
-
velocity
- u′:
-
velocity fluctuations
- Pe :
-
grid Peclet number
- Pe L :
-
global Peclet number
- X :
-
X — coordinate
- Z :
-
αU
- α:
-
volume fraction
- α′:
-
volume fraction fluctuations
- δx :
-
nodal distance
- ω:
-
normalized difference
- ν:
-
viscosity
- ζ:
-
normalized differnce
- ϱ:
-
density
- ϕ:
-
general variable
- 0:
-
locationX/L = 0
- e :
-
interface east momentum control volume
- E :
-
nodal east momentum control volume
- ec :
-
interface east continuity control volume
- Ec :
-
nodal east continuity control volume
- L :
-
locationX/L = 1
- P :
-
nodal centermomentum control volume
- Pc :
-
nodal centercontinuity control volume
- t :
-
turbulent
- U :
-
velocity
- w :
-
interface west momentum equation
- W :
-
nodal west momentum equation
- wc :
-
interface west continuity equation
- Wc :
-
nodal west continuity equation
- α:
-
volume fraction
References
Elghobashi, S.; Abou-Arab, T.; Rizk, M.; Mostafa, A. (1984): Prediction of the particle-laden jet with a two-equation turbulence model. Int. J. Multiphase Flow 10, 697–710
Han, T.; Humphrey, J. A. C.; Launder, B. E. (1981): A comparison of hybrid and quadratic-upstream differencing in high Reynolds number elliptic flows. Comput. Meth. Appl. Mech. Eng. 29, 81–95
Hinze, J.O. (1972): Turbulent fluid and particle interaction. Progress in heat and mass transfer, vol. 6, pp. 433–452. New York: Pergamon Press
Huang, P. G.; Launder, B. E.; Leschziner, M. A. (1985): Discretization of nonlinear convection process: A broad-range comparison of four schemes. Comput. Meth. Appl. Mech. Eng. 48, 1–24
Leonard, B.P. (1979): A stable and accurate convective modeling procedure based on quadratic upstream interpolation. Comput. Meth. Appl. Mech. Eng. 19, 59–98
Leschziner, M. A. (1980): Practical evaluation of three finite difference schemes for the computation of steady-state recirculating flows. Comput. Meth. Appl. Mech. Eng. 23, 293–312
Patankar, S. V. (1980): Numerical heat transfer and fluid flow. New York: McGraw-Hill
Pourahmadi, F.; Humphrey, J. A. C. (1983): Modeling solid-fluid turbulent flows with application to predicting erosive wear. Phys. Chem. Hydrodyn. 4, 191–219
Raithby, G. D. (1976): Skew upwind differencing schemes for problems involving fluid flow. Comput. Meth. Appl. Mech. Eng. 9, 153–164
Wong, H. H.; Raithby, G. D. (1979): Improved finite-differnce methods based on a critical evaluation of the approximating errors. Numer. Heat Transfer 2, 139–163
Author information
Authors and Affiliations
Additional information
Communicated by G. Yagawa, June 12, 1987
Rights and permissions
About this article
Cite this article
Fleckhaus, D., Hishida, K. & Maeda, M. An approximation of source terms in gradient form for multiphase transport processes. Computational Mechanics 3, 361–370 (1988). https://doi.org/10.1007/BF00712149
Issue Date:
DOI: https://doi.org/10.1007/BF00712149