TY - JOUR
ID - 22204
TI - A study on the accuracy of finite volume numerical models with non-rectangular mesh
JO - Scientia Iranica
JA - SCI
LA - en
SN - 1026-3098
AU - Morovvat, M.
AU - Zarrati, A. R.
AU - Jalili Ghazizadeh, M. R.
AD - Department of Water and Environmental Engineering, Shahid Beheshti University, East Vafadar Blvd., Tehranpars, Tehran, P.O. Box 1658953571, Iran
AD - Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, P.O. Box 1591634311, Iran
Y1 - 2021
PY - 2021
VL - 28
IS - 4
SP - 1963
EP - 1972
KW - Non-rectangular mesh
KW - Complex geometry
KW - Numerical error
KW - Finite volume method
KW - Velocity oscillation
KW - Discretization assumptions
KW - Differential Advection
DO - 10.24200/sci.2021.52017.2484
N2 - During numerical simulation of complex geometries and flow depth variations, non-rectangular computational cells are to be generated. However, application of this kind of mesh cause numerical errors. A 3-D model, which was verified and validated before, was used to illustrate the problem in a simple open channel flow. A zigzag computational mesh was used to study the effect of non-rectangular cells on the accuracy of the model. Results showed that water surface and velocity profiles oscillated around the correct answer. Investigating the reason for this oscillation showed that assuming constant velocity at non-rectangular computational cell surfaces, which is a usual practice in all numerical schemes, cause this error. Variation of velocity at mesh surfaces was then added to the computation model and as a result, the oscillations in velocity profiles and water surface were eliminated. Further analysis showed that this is a general problem in any finite volume model with non-rectangular mesh.
UR - http://scientiairanica.sharif.edu/article_22204.html
L1 - http://scientiairanica.sharif.edu/article_22204_d11a8ca5a148c7768bdf3e1bbabfd325.pdf
ER -