[VnV][telemac3d] Update plage example with better choices for a few keywords

- TREATMENT OF NEGATIVE DEPTHS = 2 (new default value since release 9.0) and
TIDAL FLATS = YES (default value) to improve mass conservation of water
- FREE SURFACE GRADIENT COMPATIBILITY = 0.9 to decrease spurious oscillations
- SOLVER FOR PROPAGATION = 7 (better accuracy with quite same CPU time
rather than 2)
- switch to non-hydrostatic version (default)

examples/telemac3d/plage/doc/plage.tex

@@ -52,12 +52,25 @@ is made of 8,796 triangular elements (4,561 nodes).
  \label{t3d:plage:fig:meshV}
 \end{figure}
 
-The hydrostatic version of \telemac{3D} is used.
+The time step is 0.2~s for a simulated period of 200~s.
+
+The non-hydrostatic version of \telemac{3D} is used.
 
 To solve the advection, the method of characteristics is used for velocities and
 $k-\omega$ variables.
 
-The time step is 0.2~s for a simulated period of 200~s.
+\telkey{FREE SURFACE GRADIENT COMPATIBILITY} is set to 0.9 to decrease spurious
+oscillations.
+
+GMRES (option 7) is used to solve propagation with a better accuracy with around
+the same CPU time (compared to previous choice conjugate residual, choice 2 or
+even conjugate gradient = 1).
+\\
+
+Mass conservation is greatly improved (up to machine precision) by using default
+values for keywords \telkey{TIDAL FLATS} (= YES) and
+\telkey{TREATMENT OF NEGATIVE DEPTHS} (= 2), contrary to choices for this
+example until 9.0 (NO and 1).
 
 \subsection{Physical parameters}
 

examples/telemac3d/plage/t3d_plage.cas

@@ -24,8 +24,6 @@ NUMBER OF HORIZONTAL LEVELS : 7
 /----------------------------------------------------------------------
 /                       OPTIONS NUMERIQUES
 /----------------------------------------------------------------------
-TIDAL FLATS : NO
-/
 MASS-BALANCE                                             : YES
 VERTICAL TURBULENCE MODEL                          : 7
 ACCURACY FOR DIFFUSION OF K-EPSILON                : 1.E-8
@@ -33,17 +31,13 @@ HORIZONTAL TURBULENCE MODEL                        : 7
 /
 SCHEME FOR ADVECTION OF VELOCITIES                 : 1
 /
-ACCURACY FOR DIFFUSION OF VELOCITIES               : 1.E-7
-SOLVER FOR PROPAGATION                             : 2
+/SOLVER FOR PROPAGATION 7 (GMRES) ENABLES TO GET ONE ORDER OF MAGNITUDE
+/FOR A BETTER ACCURACY WITH AROUND THE SAME CPU TIME
+SOLVER FOR PROPAGATION                             : 7 / UNTIL 9.0 : 2
 IMPLICITATION FOR DEPTH                            : 0.6
 IMPLICITATION FOR VELOCITIES                       : 0.6
-/
-/ DEFAULT VALUE UNTIL V7P3 KEPT FOR NON REGRESSION
-NON-HYDROSTATIC VERSION : NO
+/ TO DECREASE SPURIOUS OSCILLATIONS
+FREE SURFACE GRADIENT COMPATIBILITY                : 0.9
 /
 / DEFAULT VALUES UNTIL V8P0 KEPT FOR NON REGRESSION
-ACCURACY FOR PROPAGATION = 1.E-6
 SCHEME FOR ADVECTION OF K-EPSILON = 1
-/
-/ DEFAULT VALUE UNTIL V8P5 KEPT FOR NON REGRESSION
-TREATMENT OF NEGATIVE DEPTHS = 1