This is an analytical test for the accuracy of the shock speed of a density wedge.
Test Reference
- Shin, J.O.; Dalziel, S.B and Linden, P.F. (2004). "Gravity Currents Produced by Lock Exchange", Journal of Fluid Mechanics, vol 521, pp 1-34.
Domain
- Cuboid flume
- 2 m length
- 0.2 m width
- 0.2 depth
Initial Conditions
- Salt water 35 ppt on left
- Fresh water 0 ppt on right
Boundary Conditions
- Smagorinski coefficient = 0.2
- Background kinematic eddy viscosity = 1.0E-07 m2/sec
- Manning's n = 0.03
- Instantaneous barrier removal at time zero
- No defined time varying conditions
Results
- Denser salt water will slump under the fresh water
- Shock speed computed in terms of Froude Number
- Shin et al. 2004 reports 'Fh' values of 0.35 to 0.5
- This test case set up yields 'Fh' = 0.5
- Constituent state at 16 seconds, red represents denser fluid
- Mesh resolution can impact results: