From 8f71af6946de1ac1ad7e81d7ef8232b6f8b3ca09 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Chi-Tu=C3=A2n=20Pham?= <chi-tuan.pham@edf.fr>
Date: Fri, 27 Dec 2024 15:15:17 +0100
Subject: [PATCH] [VnV][telemac3d] Update bottom_bc 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 - use of gradient conjugate + preconditioning 34 = 2*17
 to solve PPE, more efficient than GMRES for this example (very few iterations
 are needed) - ACCURACY FOR DIFFUSION OF VELOCITIES = 1.E-15 as easily solved
 + PRECONDITIONING FOR DIFFUSION OF VELOCITIES = 34 to improve efficiency

---
 .../telemac3d/bottom_bc/doc/bottom_bc.tex     | 58 +++++++++++++------
 .../telemac3d/bottom_bc/f3d_bottom_inlet.slf  |  2 +-
 .../telemac3d/bottom_bc/f3d_bottom_source.slf |  2 +-
 .../telemac3d/bottom_bc/t3d_bottom_inlet.cas  | 14 ++---
 .../telemac3d/bottom_bc/t3d_bottom_source.cas | 13 ++---
 examples/telemac3d/bottom_bc/vnv_bottom_bc.py | 10 ++--
 6 files changed, 57 insertions(+), 42 deletions(-)

diff --git a/examples/telemac3d/bottom_bc/doc/bottom_bc.tex b/examples/telemac3d/bottom_bc/doc/bottom_bc.tex
index d05dd98059..fca5b0baf5 100644
--- a/examples/telemac3d/bottom_bc/doc/bottom_bc.tex
+++ b/examples/telemac3d/bottom_bc/doc/bottom_bc.tex
@@ -19,6 +19,14 @@ of 100~m placed at the centre of the bed.\\
 All vertical boundaries are defined as walls, see Figure\ref{fig:GeomPlan}.\\
 Nikuradse law with friction coefficient equal to 0.01~m is imposed on the bottom.
 
+\begin{figure}[H]
+\begin{center}
+	\includegraphics[width=0.4\textwidth]{GeomPlan.pdf}
+\end{center}
+\caption{Geometrical parameters of the test case.}
+\label{fig:GeomPlan}
+\end{figure}
+
 The depth is constant, and initially set to 500~m.
 
 \subsection{Geometry and Mesh}
@@ -27,14 +35,6 @@ The configuration of this test case is simple, it is a square box of sides
 4,000~m.
 The geometry of the test case is shown in Figure \ref{fig:GeomPlan}.
 
-\begin{figure}[t!]
-\begin{center}
-	\includegraphics[]{GeomPlan.pdf}
-\end{center}
-\caption{Geometrical parameters of the test case.}
-\label{fig:GeomPlan}
-\end{figure}
-
 Furthermore, two different meshes are used, a fine mesh made of 8,336 elements
 and 4,233 nodes (Figure \ref{fig:bottom_bc:MeshHinlet}) and a coarse mesh
 made of 2,580 elements and 1,355 nodes (Figure \ref{fig:bottom_bc:MeshHsource}).
@@ -43,13 +43,13 @@ prescribed.
 
 \begin{figure}[H]
  \centering
- \includegraphicsmaybe{[width=\textwidth]}{../img/Mesh_inlet.png}
+ \includegraphicsmaybe{[width=0.6\textwidth]}{../img/Mesh_inlet.png}
   \caption{Horizontal mesh (finer for inlet).}\label{fig:bottom_bc:MeshHinlet}
 \end{figure}
 
 \begin{figure}[H]
  \centering
- \includegraphicsmaybe{[width=\textwidth]}{../img/Mesh_source.png}
+ \includegraphicsmaybe{[width=0.6\textwidth]}{../img/Mesh_source.png}
   \caption{Horizontal mesh (coarser for source).}\label{fig:bottom_bc:MeshHsource}
 \end{figure}
 
@@ -100,10 +100,28 @@ The key numerical parameters for \telfile{t3d\_bottom\_source.cas} are:
 
 For both steering files, the N-type MURD scheme (scheme 4) is used to solve the
 advection of velocities.
+\\
 
-The time step is 1~s for the ijnection on the bed and 5~s for the source
+Using conjugate gradient (\telkey{SOLVER FOR PPE} = 1) and
+\telkey{PRECONDITIONING FOR PPE} = 34 (= 2 $\times$ 17) accelerates the solving
+of Poisson Pressure Equation, compared to default choice GMRES (= 7).
+Only very few iterations are needed to converge to the chosen accuracy.
+
+Moreover as the diffusion of velocities is easily solved
+\telkey{ACCURACY FOR DIFFUSION OF VELOCITIES} is set to 10$^{-15}$.
+Using \telkey{PRECONDITIONING FOR DIFFUSION OF VELOCITIES} = 34
+improves the efficiency to solve this step.
+\\
+
+The time step is 1~s for the injection on the bed and 5~s for the source
 discharge, both for a simulated period of 1,800~s.
+\\
+
+Mass conservation is improved (up to machine precision) by using default value
+for the keyword \telkey{TREATMENT OF NEGATIVE DEPTHS} (= 2), instead of the old
+default value = 1 (smoothings) for this example (until release 9.0).
 
+\newpage
 \section{Results}
 
 %At the moment, no post processing is done, however it would be good to have a
@@ -133,6 +151,7 @@ more important than for the source case.
  \label{fig:bottom_bc:waterdepth}
 \end{figure}
 
+\newpage
 Figure \ref{fig:bottom_bc:veloH} shows the horizontal velocity
 at the free surface for inlet (top) and source (bottom) cases.
 A circular symmetry can be seen for the inlet (top) case not
@@ -140,12 +159,12 @@ as well reproduced for the source (bottom) case.
 
 \begin{figure}[H]
 \centering
-\begin{minipage}[t]{.9\textwidth}
+\begin{minipage}[t]{.8\textwidth}
  \centering
 \includegraphicsmaybe{[width=\textwidth]}{../img/veloH_inlet.png}
 \end{minipage}
 %
-\begin{minipage}[t]{.9\textwidth}
+\begin{minipage}[t]{.8\textwidth}
  \centering
 \includegraphicsmaybe{[width=\textwidth]}{../img/veloH_source.png}
 \end{minipage}
@@ -154,13 +173,10 @@ as well reproduced for the source (bottom) case.
  \label{fig:bottom_bc:veloH}
 \end{figure}
 
+\newpage
 Figure \ref{fig:bottom_bc:veloW_inlet} shows the vertical velocity component
 along plane $y$ = 2,000~m for inlet case at 4 different time steps
 (180~s, 540~s, mid-simulation = 900~s and final time = 1,800~s) whereas
-Figure \ref{fig:bottom_bc:veloW_source} shows the vertical velocity component
-along plane $y$ = 2,000~m for source case at the same time steps.
-A constant jet with the same velocity can be better reproduced with inlet
-case than source case.
 
 \begin{figure}[H]
 \centering
@@ -188,6 +204,12 @@ case than source case.
  \label{fig:bottom_bc:veloW_inlet}
 \end{figure}
 
+\newpage
+Figure \ref{fig:bottom_bc:veloW_source} shows the vertical velocity component
+along plane $y$ = 2,000~m for source case at the same time steps.
+A constant jet with the same velocity can be better reproduced with inlet
+case than source case.
+
 \begin{figure}[H]
 \centering
 \begin{minipage}[t]{\textwidth}
@@ -214,6 +236,7 @@ case than source case.
  \label{fig:bottom_bc:veloW_source}
 \end{figure}
 
+\newpage
 Figure \ref{fig:bottom_bc:vectorial} shows the vertical velocity along $z$
 and velocity vectors along plane $y$ = 2,000~m
 for inlet (top) and source (bottom) cases.
@@ -234,6 +257,7 @@ for inlet (top) and source (bottom) cases.
  \label{fig:bottom_bc:vectorial}
 \end{figure}
 
+\newpage
 Figure \ref{fig:bottom_bc:velocityW_profile} shows the vertical velocity profile
 along $z$ at location ($x$, $y$) = (2,000 ; 2,000)
 for inlet (left) and source (right) cases.
diff --git a/examples/telemac3d/bottom_bc/f3d_bottom_inlet.slf b/examples/telemac3d/bottom_bc/f3d_bottom_inlet.slf
index 5f036395e3..e7d7e8506b 100644
--- a/examples/telemac3d/bottom_bc/f3d_bottom_inlet.slf
+++ b/examples/telemac3d/bottom_bc/f3d_bottom_inlet.slf
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:71a94cf3bf8734c0a2dbb471a81a6bc270afdba06647b132206e4fb154f0ff06
+oid sha256:bde5f1eb6281052c32a32e6c55ea25f165464fbe1b2f4c81ce7558934c3aa105
 size 6846348
diff --git a/examples/telemac3d/bottom_bc/f3d_bottom_source.slf b/examples/telemac3d/bottom_bc/f3d_bottom_source.slf
index e4f59c71a6..52137d4e86 100644
--- a/examples/telemac3d/bottom_bc/f3d_bottom_source.slf
+++ b/examples/telemac3d/bottom_bc/f3d_bottom_source.slf
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:4d4a5324a2781ad66a3d243d9e12031f04bb05496263eff729cb3aec3dcf83ac
+oid sha256:cb26ca6c9f6fcb06faa6c72f962e394fb5b1ae21fa6cd1cf302d93a95ad8b301
 size 2149452
diff --git a/examples/telemac3d/bottom_bc/t3d_bottom_inlet.cas b/examples/telemac3d/bottom_bc/t3d_bottom_inlet.cas
index c4d7ec2be5..a610238710 100644
--- a/examples/telemac3d/bottom_bc/t3d_bottom_inlet.cas
+++ b/examples/telemac3d/bottom_bc/t3d_bottom_inlet.cas
@@ -35,27 +35,23 @@ FRICTION COEFFICIENT FOR THE BOTTOM = 0.01
 /----------------------------------------------------------------------/
 MASS-BALANCE : YES
 /----------------------------------------------------------------------/
-IMPLICITATION FOR DEPTH = 1.
-/----------------------------------------------------------------------/
-TIDAL FLATS : NO
-/----------------------------------------------------------------------/
 INITIAL CONDITIONS : 'CONSTANT ELEVATION'
 INITIAL ELEVATION : 0.0
 /----------------------------------------------------------------------/
 /  NON-HYDROSTATIC PART
 /----------------------------------------------------------------------/
+SOLVER FOR PPE = 1
+PRECONDITIONING FOR PPE = 34
 MAXIMUM NUMBER OF ITERATIONS FOR PPE = 200
 ACCURACY FOR PPE = 1.E-5  / NOT 1.E-6 TO SAVE CPU TIME
-OPTION OF SOLVER FOR PPE = 10
+/OPTION OF SOLVER FOR PPE = 10 / IF USING GMRES = 7
 NON-HYDROSTATIC VERSION : YES
 /----------------------------------------------------------------------/
 /  WAVE EQUATION
 /----------------------------------------------------------------------/
 ACCURACY FOR PROPAGATION = 1.E-8
+ACCURACY FOR DIFFUSION OF VELOCITIES = 1.E-15
+PRECONDITIONING FOR DIFFUSION OF VELOCITIES = 34
 /
 / DEFAULT VALUES UNTIL V8P0 KEPT FOR NON REGRESSION
 SCHEME OPTION FOR ADVECTION OF VELOCITIES = 1
-IMPLICITATION FOR VELOCITIES = 1.
-/
-/ DEFAULT VALUE UNTIL V8P5 KEPT FOR NON REGRESSION
-TREATMENT OF NEGATIVE DEPTHS = 1
diff --git a/examples/telemac3d/bottom_bc/t3d_bottom_source.cas b/examples/telemac3d/bottom_bc/t3d_bottom_source.cas
index 52af060a70..5bdced3466 100644
--- a/examples/telemac3d/bottom_bc/t3d_bottom_source.cas
+++ b/examples/telemac3d/bottom_bc/t3d_bottom_source.cas
@@ -37,25 +37,20 @@ FRICTION COEFFICIENT FOR THE BOTTOM = 0.01
 /----------------------------------------------------------------------/
 MASS-BALANCE : YES
 /----------------------------------------------------------------------/
-IMPLICITATION FOR DEPTH = 1.
-/----------------------------------------------------------------------/
-TIDAL FLATS : NO
-/----------------------------------------------------------------------/
 INITIAL CONDITIONS : 'CONSTANT ELEVATION'
 INITIAL ELEVATION : 0.0
 /----------------------------------------------------------------------/
 /  NON-HYDROSTATIC PART
 /----------------------------------------------------------------------/
-ACCURACY FOR PPE = 1.E-6
+SOLVER FOR PPE = 1
+PRECONDITIONING FOR PPE = 34
 NON-HYDROSTATIC VERSION : YES
 /----------------------------------------------------------------------/
 /  WAVE EQUATION
 /----------------------------------------------------------------------/
 ACCURACY FOR PROPAGATION = 1.E-8
+ACCURACY FOR DIFFUSION OF VELOCITIES = 1.E-15
+PRECONDITIONING FOR DIFFUSION OF VELOCITIES = 34
 /
 / DEFAULT VALUES UNTIL V8P0 KEPT FOR NON REGRESSION
 SCHEME OPTION FOR ADVECTION OF VELOCITIES = 1
-IMPLICITATION FOR VELOCITIES = 1.
-/
-/ DEFAULT VALUE UNTIL V8P5 KEPT FOR NON REGRESSION
-TREATMENT OF NEGATIVE DEPTHS = 1
diff --git a/examples/telemac3d/bottom_bc/vnv_bottom_bc.py b/examples/telemac3d/bottom_bc/vnv_bottom_bc.py
index 20d2e11886..3fec50ebfe 100644
--- a/examples/telemac3d/bottom_bc/vnv_bottom_bc.py
+++ b/examples/telemac3d/bottom_bc/vnv_bottom_bc.py
@@ -73,27 +73,27 @@ class VnvStudy(AbstractVnvStudy):
         # Comparison with the last time frame of the reference file.
         self.check_epsilons('vnv_2:T3DRES',
                             'f3d_bottom_inlet.slf',
-                            eps=[1.E-8])
+                            eps=[3.E-8])
 
         # Comparison between sequential and parallel run.
         self.check_epsilons('vnv_1:T3DRES',
                             'vnv_2:T3DRES',
-                            eps=[1.E-8])
+                            eps=[3.E-8])
 
         # Comparison with the last time frame of the reference file.
         self.check_epsilons('vnv_3:T3DRES',
                             'f3d_bottom_source.slf',
-                            eps=[1.E-8])
+                            eps=[1.E-9])
 
         # Comparison with the last time frame of the reference file.
         self.check_epsilons('vnv_4:T3DRES',
                             'f3d_bottom_source.slf',
-                            eps=[1.E-8])
+                            eps=[1.E-9])
 
         # Comparison between sequential and parallel run.
         self.check_epsilons('vnv_3:T3DRES',
                             'vnv_4:T3DRES',
-                            eps=[1.E-8])
+                            eps=[1.E-9])
 
 
     def _post(self):
-- 
GitLab