New URL for NEMO forge!   http://forge.nemo-ocean.eu

Since March 2022 along with NEMO 4.2 release, the code development moved to a self-hosted GitLab.
This present forge is now archived and remained online for history.
Changeset 12178 for NEMO/branches/2019/dev_r11078_OSMOSIS_IMMERSE_Nurser/doc/latex/NEMO/subfiles/chap_conservation.tex – NEMO

Ignore:
Timestamp:
2019-12-11T12:02:38+01:00 (4 years ago)
Author:
agn
Message:

updated trunk to v 11653

Location:
NEMO/branches/2019/dev_r11078_OSMOSIS_IMMERSE_Nurser/doc
Files:
5 edited

Legend:

Unmodified
Added
Removed
  • NEMO/branches/2019/dev_r11078_OSMOSIS_IMMERSE_Nurser/doc

    • Property svn:ignore deleted
    • Property svn:externals set to
      ^/utils/badges badges
      ^/utils/logos logos
  • NEMO/branches/2019/dev_r11078_OSMOSIS_IMMERSE_Nurser/doc/latex

    • Property svn:ignore deleted
  • NEMO/branches/2019/dev_r11078_OSMOSIS_IMMERSE_Nurser/doc/latex/NEMO

    • Property svn:externals set to
      ^/utils/figures/NEMO figures
  • NEMO/branches/2019/dev_r11078_OSMOSIS_IMMERSE_Nurser/doc/latex/NEMO/subfiles

    • Property svn:ignore set to
      *.ind
      *.ilg
  • NEMO/branches/2019/dev_r11078_OSMOSIS_IMMERSE_Nurser/doc/latex/NEMO/subfiles/chap_conservation.tex

    r11123 r12178  
    33\begin{document} 
    44 
    5 % ================================================================ 
    6 % Invariant of the Equations 
    7 % ================================================================ 
    85\chapter{Invariants of the Primitive Equations} 
    9 \label{chap:Invariant} 
    10 \minitoc 
     6\label{chap:CONS} 
     7 
     8\thispagestyle{plain} 
     9 
     10\chaptertoc 
     11 
     12\paragraph{Changes record} ~\\ 
     13 
     14{\footnotesize 
     15  \begin{tabularx}{\textwidth}{l||X|X} 
     16    Release & Author(s) & Modifications \\ 
     17    \hline 
     18    {\em   4.0} & {\em ...} & {\em ...} \\ 
     19    {\em   3.6} & {\em ...} & {\em ...} \\ 
     20    {\em   3.4} & {\em ...} & {\em ...} \\ 
     21    {\em <=3.4} & {\em ...} & {\em ...} 
     22  \end{tabularx} 
     23} 
     24 
     25\clearpage 
    1126 
    1227The continuous equations of motion have many analytic properties. 
     
    3550The alternative is to use diffusive schemes such as upstream or flux corrected schemes. 
    3651This last option was rejected because we prefer a complete handling of the model diffusion, 
    37 \ie of the model physics rather than letting the advective scheme produces its own implicit diffusion without 
     52\ie\ of the model physics rather than letting the advective scheme produces its own implicit diffusion without 
    3853controlling the space and time structure of this implicit diffusion. 
    3954Note that in some very specific cases as passive tracer studies, the positivity of the advective scheme is required. 
     
    4156\citep{Marti1992?, Levy1996?, Levy1998?}. 
    4257 
    43 % ------------------------------------------------------------------------------------------------------------- 
    44 %       Conservation Properties on Ocean Dynamics 
    45 % ------------------------------------------------------------------------------------------------------------- 
     58%% ================================================================================================= 
    4659\section{Conservation properties on ocean dynamics} 
    47 \label{sec:Invariant_dyn} 
     60\label{sec:CONS_Invariant_dyn} 
    4861 
    4962The non linear term of the momentum equations has been split into a vorticity term, 
     
    6376The continuous formulation of the vorticity term satisfies following integral constraints: 
    6477\[ 
    65   % \label{eq:vor_vorticity} 
     78  % \label{eq:CONS_vor_vorticity} 
    6679  \int_D {{\textbf {k}}\cdot \frac{1}{e_3 }\nabla \times \left( {\varsigma 
    67         \;{\rm {\bf k}}\times {\textbf {U}}_h } \right)\;dv} =0 
    68 \] 
    69  
    70 \[ 
    71   % \label{eq:vor_enstrophy} 
     80        \;{\mathrm {\mathbf k}}\times {\textbf {U}}_h } \right)\;dv} =0 
     81\] 
     82 
     83\[ 
     84  % \label{eq:CONS_vor_enstrophy} 
    7285  if\quad \chi =0\quad \quad \int\limits_D {\varsigma \;{\textbf{k}}\cdot 
    7386    \frac{1}{e_3 }\nabla \times \left( {\varsigma {\textbf{k}}\times {\textbf{U}}_h } \right)\;dv} =-\int\limits_D {\frac{1}{2}\varsigma ^2\,\chi \;dv} 
     
    7689 
    7790\[ 
    78   % \label{eq:vor_energy} 
     91  % \label{eq:CONS_vor_energy} 
    7992  \int_D {{\textbf{U}}_h \times \left( {\varsigma \;{\textbf{k}}\times {\textbf{U}}_h } \right)\;dv} =0 
    8093\] 
     
    88101Using the symmetry or anti-symmetry properties of the operators (Eqs II.1.10 and 11), 
    89102it can be shown that the scheme (II.2.11) satisfies (II.4.1b) but not (II.4.1c), 
    90 while scheme (II.2.12) satisfies (II.4.1c) but not (II.4.1b) (see appendix C).  
     103while scheme (II.2.12) satisfies (II.4.1c) but not (II.4.1b) (see appendix C). 
    91104Note that the enstrophy conserving scheme on total vorticity has been chosen as the standard discrete form of 
    92105the vorticity term. 
     
    102115the horizontal gradient of horizontal kinetic energy: 
    103116 
    104 \begin{equation} \label{eq:keg_zad} 
    105 \int_D {{\textbf{U}}_h \cdot \nabla _h \left( {1/2\;{\textbf{U}}_h ^2} \right)\;dv} =-\int_D {{\textbf{U}}_h \cdot \frac{w}{e_3 }\;\frac{\partial  
     117\begin{equation} \label{eq:CONS_keg_zad} 
     118\int_D {{\textbf{U}}_h \cdot \nabla _h \left( {1/2\;{\textbf{U}}_h ^2} \right)\;dv} =-\int_D {{\textbf{U}}_h \cdot \frac{w}{e_3 }\;\frac{\partial 
    106119{\textbf{U}}_h }{\partial k}\;dv} 
    107120\end{equation} 
    108121 
    109122Using the discrete form given in {\S}II.2-a and the symmetry or anti-symmetry properties of 
    110 the mean and difference operators, \autoref{eq:keg_zad} is demonstrated in the Appendix C. 
    111 The main point here is that satisfying \autoref{eq:keg_zad} links the choice of the discrete forms of 
     123the mean and difference operators, \autoref{eq:CONS_keg_zad} is demonstrated in the Appendix C. 
     124The main point here is that satisfying \autoref{eq:CONS_keg_zad} links the choice of the discrete forms of 
    112125the vertical advection and of the horizontal gradient of horizontal kinetic energy. 
    113126Choosing one imposes the other. 
     
    122135This properties is satisfied locally with the choice of discretization we have made (property (II.1.9)~). 
    123136In addition, when the equation of state is linear 
    124 (\ie when an advective-diffusive equation for density can be derived from those of temperature and salinity) 
     137(\ie\ when an advective-diffusive equation for density can be derived from those of temperature and salinity) 
    125138the change of horizontal kinetic energy due to the work of pressure forces is balanced by the change of 
    126139potential energy due to buoyancy forces: 
    127140 
    128141\[ 
    129   % \label{eq:hpg_pe} 
     142  % \label{eq:CONS_hpg_pe} 
    130143  \int_D {-\frac{1}{\rho_o }\left. {\nabla p^h} \right|_z \cdot {\textbf {U}}_h \;dv} \;=\;\int_D {\nabla .\left( {\rho \,{\textbf{U}}} \right)\;g\;z\;\;dv} 
    131144\] 
     
    133146Using the discrete form given in {\S}~II.2-a and the symmetry or anti-symmetry properties of 
    134147the mean and difference operators, (II.4.3) is demonstrated in the Appendix C. 
    135 The main point here is that satisfying (II.4.3) strongly constraints the discrete expression of the depth of  
     148The main point here is that satisfying (II.4.3) strongly constraints the discrete expression of the depth of 
    136149$T$-points and of the term added to the pressure gradient in $s-$coordinates: the depth of a $T$-point, $z_T$, 
    137150is defined as the sum the vertical scale factors at $w$-points starting from the surface. 
     
    145158Nevertheless, the $\psi$-equation is solved numerically by an iterative solver (see {\S}~III.5), 
    146159thus the property is only satisfied with the accuracy required on the solver. 
    147 In addition, with the rigid-lid approximation, the change of horizontal kinetic energy due to the work of  
     160In addition, with the rigid-lid approximation, the change of horizontal kinetic energy due to the work of 
    148161surface pressure forces is exactly zero: 
    149162\[ 
    150   % \label{eq:spg} 
     163  % \label{eq:CONS_spg} 
    151164  \int_D {-\frac{1}{\rho_o }\nabla _h } \left( {p_s } \right)\cdot {\textbf{U}}_h \;dv=0 
    152165\] 
     
    157170otherwise there is no guarantee that the surface pressure force work vanishes. 
    158171 
    159 % ------------------------------------------------------------------------------------------------------------- 
    160 %       Conservation Properties on Ocean Thermodynamics 
    161 % ------------------------------------------------------------------------------------------------------------- 
     172%% ================================================================================================= 
    162173\section{Conservation properties on ocean thermodynamics} 
    163 \label{sec:Invariant_tra} 
     174\label{sec:CONS_Invariant_tra} 
    164175 
    165176In continuous formulation, the advective terms of the tracer equations conserve the tracer content and 
    166177the quadratic form of the tracer, \ie 
    167178\[ 
    168   % \label{eq:tra_tra2} 
     179  % \label{eq:CONS_tra_tra2} 
    169180  \int_D {\nabla .\left( {T\;{\textbf{U}}} \right)\;dv} =0 
    170181  \;\text{and} 
     
    176187Note that in both continuous and discrete formulations, there is generally no strict conservation of mass, 
    177188since the equation of state is non linear with respect to $T$ and $S$. 
    178 In practice, the mass is conserved with a very good accuracy.  
    179  
    180 % ------------------------------------------------------------------------------------------------------------- 
    181 %       Conservation Properties on Momentum Physics 
    182 % ------------------------------------------------------------------------------------------------------------- 
     189In practice, the mass is conserved with a very good accuracy. 
     190 
     191%% ================================================================================================= 
    183192\subsection{Conservation properties on momentum physics} 
    184 \label{subsec:Invariant_dyn_physics} 
     193\label{subsec:CONS_Invariant_dyn_physics} 
    185194 
    186195\textbf{* lateral momentum diffusion term} 
     
    188197The continuous formulation of the horizontal diffusion of momentum satisfies the following integral constraints~: 
    189198\[ 
    190   % \label{eq:dynldf_dyn} 
    191   \int\limits_D {\frac{1}{e_3 }{\rm {\bf k}}\cdot \nabla \times \left[ {\nabla 
     199  % \label{eq:CONS_dynldf_dyn} 
     200  \int\limits_D {\frac{1}{e_3 }{\mathrm {\mathbf k}}\cdot \nabla \times \left[ {\nabla 
    192201        _h \left( {A^{lm}\;\chi } \right)-\nabla _h \times \left( {A^{lm}\;\zeta 
    193             \;{\rm {\bf k}}} \right)} \right]\;dv} =0 
    194 \] 
    195  
    196 \[ 
    197   % \label{eq:dynldf_div} 
     202            \;{\mathrm {\mathbf k}}} \right)} \right]\;dv} =0 
     203\] 
     204 
     205\[ 
     206  % \label{eq:CONS_dynldf_div} 
    198207  \int\limits_D {\nabla _h \cdot \left[ {\nabla _h \left( {A^{lm}\;\chi } 
    199         \right)-\nabla _h \times \left( {A^{lm}\;\zeta \;{\rm {\bf k}}} \right)} 
     208        \right)-\nabla _h \times \left( {A^{lm}\;\zeta \;{\mathrm {\mathbf k}}} \right)} 
    200209    \right]\;dv} =0 
    201210\] 
    202211 
    203212\[ 
    204   % \label{eq:dynldf_curl} 
    205   \int_D {{\rm {\bf U}}_h \cdot \left[ {\nabla _h \left( {A^{lm}\;\chi } 
    206         \right)-\nabla _h \times \left( {A^{lm}\;\zeta \;{\rm {\bf k}}} \right)} 
     213  % \label{eq:CONS_dynldf_curl} 
     214  \int_D {{\mathrm {\mathbf U}}_h \cdot \left[ {\nabla _h \left( {A^{lm}\;\chi } 
     215        \right)-\nabla _h \times \left( {A^{lm}\;\zeta \;{\mathrm {\mathbf k}}} \right)} 
    207216    \right]\;dv} \leqslant 0 
    208217\] 
    209218 
    210219\[ 
    211   % \label{eq:dynldf_curl2} 
    212   \mbox{if}\quad A^{lm}=cste\quad \quad \int_D {\zeta \;{\rm {\bf k}}\cdot 
     220  % \label{eq:CONS_dynldf_curl2} 
     221  \mbox{if}\quad A^{lm}=cste\quad \quad \int_D {\zeta \;{\mathrm {\mathbf k}}\cdot 
    213222    \nabla \times \left[ {\nabla _h \left( {A^{lm}\;\chi } \right)-\nabla _h 
    214         \times \left( {A^{lm}\;\zeta \;{\rm {\bf k}}} \right)} \right]\;dv} 
     223        \times \left( {A^{lm}\;\zeta \;{\mathrm {\mathbf k}}} \right)} \right]\;dv} 
    215224  \leqslant 0 
    216225\] 
    217226 
    218227\[ 
    219   % \label{eq:dynldf_div2} 
     228  % \label{eq:CONS_dynldf_div2} 
    220229  \mbox{if}\quad A^{lm}=cste\quad \quad \int_D {\chi \;\nabla _h \cdot \left[ 
    221230      {\nabla _h \left( {A^{lm}\;\chi } \right)-\nabla _h \times \left( 
    222           {A^{lm}\;\zeta \;{\rm {\bf k}}} \right)} \right]\;dv} \leqslant 0 
    223 \] 
    224  
     231          {A^{lm}\;\zeta \;{\mathrm {\mathbf k}}} \right)} \right]\;dv} \leqslant 0 
     232\] 
    225233 
    226234(II.4.6a) and (II.4.6b) means that the horizontal diffusion of momentum conserve both the potential vorticity and 
     
    250258 
    251259\[ 
    252   % \label{eq:dynzdf_dyn} 
     260  % \label{eq:CONS_dynzdf_dyn} 
    253261  \begin{aligned} 
    254262    & \int_D {\frac{1}{e_3 }}  \frac{\partial }{\partial k}\left( \frac{A^{vm}}{e_3 }\frac{\partial {\textbf{U}}_h }{\partial k} \right) \;dv = \overrightarrow{\textbf{0}} \\ 
     
    258266conservation of vorticity, dissipation of enstrophy 
    259267\[ 
    260   % \label{eq:dynzdf_vor} 
    261   \begin{aligned} 
    262     & \int_D {\frac{1}{e_3 }{\rm {\bf k}}\cdot \nabla \times \left( {\frac{1}{e_3 
    263           }\frac{\partial }{\partial k}\left( {\frac{A^{vm}}{e_3 }\frac{\partial {\rm 
    264                   {\bf U}}_h }{\partial k}} \right)} \right)\;dv} =0 \\ 
    265     & \int_D {\zeta \,{\rm {\bf k}}\cdot \nabla \times \left( {\frac{1}{e_3 
    266           }\frac{\partial }{\partial k}\left( {\frac{A^{vm}}{e_3 }\frac{\partial {\rm 
    267                   {\bf U}}_h }{\partial k}} \right)} \right)\;dv} \leq 0 \\ 
     268  % \label{eq:CONS_dynzdf_vor} 
     269  \begin{aligned} 
     270    & \int_D {\frac{1}{e_3 }{\mathrm {\mathbf k}}\cdot \nabla \times \left( {\frac{1}{e_3 
     271          }\frac{\partial }{\partial k}\left( {\frac{A^{vm}}{e_3 }\frac{\partial {\mathrm 
     272                  {\mathbf U}}_h }{\partial k}} \right)} \right)\;dv} =0 \\ 
     273    & \int_D {\zeta \,{\mathrm {\mathbf k}}\cdot \nabla \times \left( {\frac{1}{e_3 
     274          }\frac{\partial }{\partial k}\left( {\frac{A^{vm}}{e_3 }\frac{\partial {\mathrm 
     275                  {\mathbf U}}_h }{\partial k}} \right)} \right)\;dv} \leq 0 \\ 
    268276  \end{aligned} 
    269277\] 
    270278conservation of horizontal divergence, dissipation of square of the horizontal divergence 
    271279\[ 
    272   % \label{eq:dynzdf_div} 
     280  % \label{eq:CONS_dynzdf_div} 
    273281  \begin{aligned} 
    274282    &\int_D {\nabla \cdot \left( {\frac{1}{e_3 }\frac{\partial }{\partial 
    275             k}\left( {\frac{A^{vm}}{e_3 }\frac{\partial {\rm {\bf U}}_h }{\partial k}} 
     283            k}\left( {\frac{A^{vm}}{e_3 }\frac{\partial {\mathrm {\mathbf U}}_h }{\partial k}} 
    276284          \right)} \right)\;dv} =0 \\ 
    277285    & \int_D {\chi \;\nabla \cdot \left( {\frac{1}{e_3 }\frac{\partial }{\partial 
    278             k}\left( {\frac{A^{vm}}{e_3 }\frac{\partial {\rm {\bf U}}_h }{\partial k}} 
     286            k}\left( {\frac{A^{vm}}{e_3 }\frac{\partial {\mathrm {\mathbf U}}_h }{\partial k}} 
    279287          \right)} \right)\;dv} \leq 0 \\ 
    280288  \end{aligned} 
     
    283291In discrete form, all these properties are satisfied in $z$-coordinate (see Appendix C). 
    284292In $s$-coordinates, only first order properties can be demonstrated, 
    285 \ie the vertical momentum physics conserve momentum, potential vorticity, and horizontal divergence. 
    286  
    287 % ------------------------------------------------------------------------------------------------------------- 
    288 %       Conservation Properties on Tracer Physics 
    289 % ------------------------------------------------------------------------------------------------------------- 
     293\ie\ the vertical momentum physics conserve momentum, potential vorticity, and horizontal divergence. 
     294 
     295%% ================================================================================================= 
    290296\subsection{Conservation properties on tracer physics} 
    291 \label{subsec:Invariant_tra_physics} 
     297\label{subsec:CONS_Invariant_tra_physics} 
    292298 
    293299The numerical schemes used for tracer subgridscale physics are written in such a way that 
    294300the heat and salt contents are conserved (equations in flux form, second order centred finite differences). 
    295301As a form flux is used to compute the temperature and salinity, 
    296 the quadratic form of these quantities (\ie their variance) globally tends to diminish. 
     302the quadratic form of these quantities (\ie\ their variance) globally tends to diminish. 
    297303As for the advective term, there is generally no strict conservation of mass even if, 
    298 in practice, the mass is conserved with a very good accuracy.  
    299  
    300 \textbf{* lateral physics: }conservation of tracer, dissipation of tracer  
     304in practice, the mass is conserved with a very good accuracy. 
     305 
     306\textbf{* lateral physics: }conservation of tracer, dissipation of tracer 
    301307variance, i.e. 
    302308 
    303309\[ 
    304   % \label{eq:traldf_t_t2} 
     310  % \label{eq:CONS_traldf_t_t2} 
    305311  \begin{aligned} 
    306312    &\int_D \nabla\, \cdot\, \left( A^{lT} \,\Re \,\nabla \,T \right)\;dv = 0 \\ 
     
    312318 
    313319\[ 
    314   % \label{eq:trazdf_t_t2} 
     320  % \label{eq:CONS_trazdf_t_t2} 
    315321  \begin{aligned} 
    316322    & \int_D \frac{1}{e_3 } \frac{\partial }{\partial k}\left( \frac{A^{vT}}{e_3 }  \frac{\partial T}{\partial k}  \right)\;dv = 0 \\ 
     
    328334It has not been implemented. 
    329335 
    330 \biblio 
    331  
    332 \pindex 
     336\onlyinsubfile{\input{../../global/epilogue}} 
    333337 
    334338\end{document} 
Note: See TracChangeset for help on using the changeset viewer.