diff +rv/+time/RungekuttaRvMultiGrid.m @ 1174:b96b1245a77d feature/rv

Update variable names and comments in RungekuttaRvMultiGrid
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Fri, 28 Jun 2019 13:33:49 +0200
parents d02e5b8a0b24
children ebec2b86f539
line wrap: on
line diff
--- a/+rv/+time/RungekuttaRvMultiGrid.m	Fri Jun 28 13:24:45 2019 +0200
+++ b/+rv/+time/RungekuttaRvMultiGrid.m	Fri Jun 28 13:33:49 2019 +0200
@@ -9,7 +9,7 @@
         rkScheme  % The particular RK scheme used for time integration
         RV              % Residual Viscosity operator
         DvDt            % Function for computing the time deriative used for the RV evaluation
-        v_unstable
+        v_coarse
         viscosity
     end
     methods
@@ -34,7 +34,7 @@
         
             obj.RV = RV;
             obj.DvDt = DvDt;
-            obj.v_unstable = 0*v0;
+            obj.v_coarse = 0*v0;
             obj.viscosity = 0*v0;
         end
 
@@ -44,20 +44,23 @@
         end
 
         function state = getState(obj)
-            dvdt = obj.DvDt(obj.v_unstable);
+            dvdt = obj.DvDt(obj.v_coarse);
             [viscosity, Df, firstOrderViscosity, residualViscosity] = obj.RV.evaluate(obj.v, dvdt);
             state = struct('v', obj.v, 'dvdt', dvdt, 'Df', Df, 'viscosity', obj.viscosity, 'residualViscosity', residualViscosity, 'firstOrderViscosity', firstOrderViscosity, 't', obj.t);
         end
 
         % Advances the solution vector one time step using the Runge-Kutta method given by
         % obj.coeffs, using a fixed residual viscosity for the Runge-Kutta substeps
-        function obj = step(obj)            
+        function obj = step(obj)
+            % Fix the viscosity of the stabilized RHS            
             m = length(obj.viscosity);
-            obj.v_unstable = obj.rkScheme(obj.v, obj.t, obj.k, obj.F_coarse);
-            obj.viscosity = obj.RV.evaluateViscosity(obj.v, obj.DvDt(obj.v_unstable));
-            % Fix the viscosity of the stabilized RHS
             F_stable = @(v,t) obj.F(v,t,spdiags(obj.viscosity,0,m,m));
+            % Advance solution on unstabilized coarse mesh based on current solution
+            obj.v_coarse = obj.rkScheme(obj.v, obj.t, obj.k, obj.F_coarse);
+            % Advance solution on on stabilized mesh based on current viscosity
             obj.v = obj.rkScheme(obj.v, obj.t, obj.k, F_stable);
+            % Compute viscosity for the next time time level using the advanced solution
+            obj.viscosity = obj.RV.evaluateViscosity(obj.v, obj.DvDt(obj.v_coarse));
             obj.t = obj.t + obj.k;
             obj.n = obj.n + 1;
         end