Cover Image

Direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio

Direct numerical simulation; Fluid mechanics; Gravitation; Gravity waves; Numerical models; Reynolds number; Vortex flow; Critical regimes; Gravity currents; Kelvin-Helmholtz; Size and shape; Strong stratification; Subcritical flow; Supercritical flow; Weak stratification; Aspect ratio

Saved in:
Bibliographic Details
Main Authors: Lam W.K., Chan L., Hasini H., Ooi A.
Other Authors: 57205240468
Format: Conference Paper
Published: Australasian Fluid Mechanics Society 2023
Tags: Add Tag
No Tags, Be the first to tag this record!
id my.uniten.dspace-23940
record_format dspace
spelling my.uniten.dspace-239402023-05-29T14:53:20Z Direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio Lam W.K. Chan L. Hasini H. Ooi A. 57205240468 57139456500 6507435998 7005905452 Direct numerical simulation; Fluid mechanics; Gravitation; Gravity waves; Numerical models; Reynolds number; Vortex flow; Critical regimes; Gravity currents; Kelvin-Helmholtz; Size and shape; Strong stratification; Subcritical flow; Supercritical flow; Weak stratification; Aspect ratio Direct numerical simulations (DNSs) of two-dimensional stratified gravity current are carried out using OpenFOAM. Three different aspect ratios, h0/l0 (where h0 is the height of the dense fluid and l0 is the length of the dense fluid) are simulated with stratification strength, S=0.2, 0.5, and 0.8. Reynolds number is kept constant at Re=4000. For the equivalent h0/l0 ratio, the stratification strength reduces the front velocity, uf and results in a shorter front location, xf-l0. Stratification strength has a strong effect on the size and shape of the gravity current. Gravity current with aspect ratio, h0/l0 of 0.25 propagating in the stratified ambient of S=0.2 and 0.5 experienced two acceleration phases. Qualitiative analysis of contours ranging from subcritical to supercritical flow in comparison to the flow structures was presented in this study. Subcritical flow was smooth and minimal vortices formed in the head of the gravity current was obtained in all the cases with strong stratification strength, S=0.8. Supercritical flow occurs in weak stratification with h0/l0=1 and 4. Strong vortices formed in the head of the gravity current followed by Kelvin-Helmholtz (K-H) billows at the back of the head. The propagation of the internal waves was faster than the gravity current flow in the subcritical regime. Case h0/l0=4 with S=0.5 had the Froude number closest to the critical regime (Fr=0.324 ? 1/?) and can be deemed to be in the critical regime. � 2018 Australasian Fluid Mechanics Society. All rights reserved. Final 2023-05-29T06:53:19Z 2023-05-29T06:53:19Z 2018 Conference Paper 2-s2.0-85084096977 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85084096977&partnerID=40&md5=03e1705d65a505e05b047afd60ce9eb9 https://irepository.uniten.edu.my/handle/123456789/23940 Australasian Fluid Mechanics Society Scopus
institution Universiti Tenaga Nasional
building UNITEN Library
collection Institutional Repository
continent Asia
country Malaysia
content_provider Universiti Tenaga Nasional
content_source UNITEN Institutional Repository
url_provider http://dspace.uniten.edu.my/
description Direct numerical simulation; Fluid mechanics; Gravitation; Gravity waves; Numerical models; Reynolds number; Vortex flow; Critical regimes; Gravity currents; Kelvin-Helmholtz; Size and shape; Strong stratification; Subcritical flow; Supercritical flow; Weak stratification; Aspect ratio
author2 57205240468
author_facet 57205240468
Lam W.K.
Chan L.
Hasini H.
Ooi A.
format Conference Paper
author Lam W.K.
Chan L.
Hasini H.
Ooi A.
spellingShingle Lam W.K.
Chan L.
Hasini H.
Ooi A.
Direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio
author_sort Lam W.K.
title Direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio
title_short Direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio
title_full Direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio
title_fullStr Direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio
title_full_unstemmed Direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio
title_sort direct numerical simulation of two-dimensional stratified gravity current flow with varying stratification and aspect ratio
publisher Australasian Fluid Mechanics Society
publishDate 2023
_version_ 1806427370657153024
score 13.211869

Similar Items