Dispersion

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Revision as of 00:06, 18 June 2012 Popinet (Talk | contribs) (added cfl = 0.25) ← Previous diff		Revision as of 00:21, 18 June 2012 Popinet (Talk | contribs) Next diff →
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-	This is a series of test of dispersion properties using a variation of the [http://gerris.dalembert.upmc.fr/gerris/examples/examples/hump.html hump example].	+	This is a series of tests of dispersion properties using a variation of the [http://gerris.dalembert.upmc.fr/gerris/examples/examples/hump.html hump example].
	{| align="center"		{| align="center"
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	| [[Image:hump-nolimiter.png|thumb|left|300px|GfsRiver, no limiter, non-linear]]		| [[Image:hump-nolimiter.png|thumb|left|300px|GfsRiver, no limiter, non-linear]]
	| [[Image:hump-nolimiter-0.25.png|thumb|left|300px|GfsRiver, no limiter, non-linear, cfl = 0.25]]		| [[Image:hump-nolimiter-0.25.png|thumb|left|300px|GfsRiver, no limiter, non-linear, cfl = 0.25]]
		+	|-
		+	| [[Image:hump-nolimiter-9.png|thumb|left|300px|GfsRiver, no limiter, non-linear, maxlevel = 9]]
	|}		|}

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Revision as of 00:21, 18 June 2012

This is a series of tests of dispersion properties using a variation of the hump example.

Final free surface (t = 1.8)

GfsAtmosphere, C-grid, BCG scheme, linearised	GfsAtmosphere, A-grid, BCG scheme, linearised
GfsRiver, minmod limiter, non-linear	GfsRiver, Sweby limiter, non-linear
GfsRiver, no limiter, non-linear	GfsRiver, no limiter, non-linear, cfl = 0.25
GfsRiver, no limiter, non-linear, maxlevel = 9

Parameter files

For GfsRiver

2 2 GfsRiver GfsBox GfsGEdge { x = 0.5 y = 0.5 } {
    Refine 8
    Init {} {
	# Parabolic hump
	Zb = 0.8*exp(-5.*(x - 0.9)*(x - 0.9) - 50.*(y - 0.5)*(y - 0.5))
	# Initial free surface and perturbation
	P = (1. + 0.01*exp(-2000.*(x - 0.1)*(x - 0.1)) - Zb)
    }
    PhysicalParams { g = 1 }
    AdvectionParams { cfl = 0.5 }
    AdaptGradient { istep = 1 } { 
    	cmax = 1e-4
    	cfactor = 2
    	maxlevel = 8
    	minlevel = 6
    } (P + Zb)
    Time { end = 1.8 }
    OutputTime { istep = 10 } stderr
    OutputSimulation { istep = 10 } stdout
    GModule gfsview
    OutputView { step = 2e-2 } { ppm2mpeg > hump.mpg } hump.gfv
    OutputSimulation { start = 0.6 step = 0.3 } sim-%g.gfs
    EventScript { start = end } {
	for i in 0.6 0.9 1.2 1.5 1.8; do
	    echo "Save stdout { format = EPS line_width = 0.2 }" | \
		gfsview-batch2D sim-$i.gfs isolines.gfv > iso-$i.eps
	    echo "Save stdout { format = EPS line_width = 0.2 }" | \
		gfsview-batch2D sim-$i.gfs cells.gfv > cells-$i.eps
	done
	echo "Save stdout { width = 1280 height = 960 }" | \
	    gfsview-batch2D sim-0.9.gfs hump.gfv | convert ppm:- hump.eps
    }
}
GfsBox {
    top = Boundary { BcNeumann V 0 }
    bottom = Boundary { BcNeumann V 0 }
}
GfsBox {
    top = Boundary { BcNeumann V 0 }
    bottom = Boundary { BcNeumann V 0 }
}
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and for GfsAtmosphere

2 2 GfsAtmosphere GfsBox GfsGEdge { x = 0.5 y = 0.5 } {
    Refine 8
    VariableTracer P { gradient = gfs_center_minmod_gradient }
    Init {} {
	# Parabolic hump
	Zb = 0.8*exp(-5.*(x - 0.9)*(x - 0.9) - 50.*(y - 0.5)*(y - 0.5))
	# Initial free surface and perturbation
	P = (1. + 0.01*exp(-2000.*(x - 0.1)*(x - 0.1)) - Zb)
    }
    Time { end = 1.8 dtmax = 2e-3 }
    OutputTime { istep = 1 } stderr
    OutputSimulation { istep = 10 } stdout
    OutputSimulation { start = 0.6 step = 0.3 } sim-%g.gfs
    GModule gfsview
    OutputView { step = 2e-2 } { ppm2mpeg > hump.mpg } hump.gfv
}
GfsBox {}
GfsBox {}
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