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annotate +rv/ResidualViscosity.m @ 1039:a8ee5eca0e6c feature/burgers1d

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Allow for the residual normalization function to return a vector. Also change the default normalization from normalizing on norm(u-mean(u),inf) to norm(u/2), since this proved to be better for 1d burgers
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Fri, 18 Jan 2019 09:06:20 +0100
parents 2ef20d00b386
children 922996695952
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
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1 classdef ResidualViscosity < handle
1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
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2 properties
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2d7c1333bd6c Add support for using the ODE to approximate the time derivative in the residual
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3 Df % Diff op approximating the gradient of the flux f(u)
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1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
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4 waveSpeed % Wave speed at each grid point, e.g f'(u). %TBD: Better naming?
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4b42999874c0 Add lower level for boot-strapping to RungeKuttaExteriorRV
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5 Cmax % Constant controlling relative amount of upwind dissipation
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6 Cres % Constant controling relative amount of upwind dissipation
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7 h % Length scale used for scaling the viscosity. Typically grid spacing.
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8 normalization % Function used to normalize the residual such that it is amplified in the
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9 % shocks.
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1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
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10 end
1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
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1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
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12 methods
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parents: 1015
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13 % TBD: Decide on how to treat waveSpeed. It would be nice to just pass a constant value without
4b42999874c0 Add lower level for boot-strapping to RungeKuttaExteriorRV
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parents: 1015
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14 % wrapping it in a function.
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2d7c1333bd6c Add support for using the ODE to approximate the time derivative in the residual
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15 function obj = ResidualViscosity(Df, waveSpeed, Cmax, Cres, h, normalization)
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a8ee5eca0e6c Allow for the residual normalization function to return a vector. Also change the default normalization from normalizing on norm(u-mean(u),inf) to norm(u/2), since this proved to be better for 1d burgers
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
parents: 1031
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16 default_arg('normalization',@(v)norm(v/2,inf));
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17 obj.Df = Df;
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18 obj.waveSpeed = waveSpeed;
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19 obj.h = h;
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20 obj.Cmax = Cmax;
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21 obj.Cres = Cres;
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22 obj.normalization = normalization;
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23 end
1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
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24
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2ef20d00b386 For easier comparison, return both the first order and residual viscosity when evaluating the residual. Add the first order and residual viscosity to the state of the RungekuttaRV time steppers
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
parents: 1017
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25 function [viscosity, Df, firstOrderViscosity, residualViscosity] = evaluate(obj, v, dvdt)
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parents: 1016
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26 Df = obj.Df(v);
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2ef20d00b386 For easier comparison, return both the first order and residual viscosity when evaluating the residual. Add the first order and residual viscosity to the state of the RungekuttaRV time steppers
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
parents: 1017
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27 firstOrderViscosity = obj.Cmax*obj.h*abs(obj.waveSpeed(v));
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a8ee5eca0e6c Allow for the residual normalization function to return a vector. Also change the default normalization from normalizing on norm(u-mean(u),inf) to norm(u/2), since this proved to be better for 1d burgers
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
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28 residualViscosity = obj.Cres*obj.h^2*abs(dvdt + Df)./obj.normalization(v);
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2ef20d00b386 For easier comparison, return both the first order and residual viscosity when evaluating the residual. Add the first order and residual viscosity to the state of the RungekuttaRV time steppers
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
parents: 1017
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29 viscosity = min(firstOrderViscosity, residualViscosity);
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30 end
1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
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31 end
1e437c9e5132 Create residual viscosity package +rv and generalize the ResidualViscosity class
Vidar Stiernström <vidar.stiernstrom@it.uu.se>
parents:
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32 end