--- manual/s_phys_pkgs/text/obcs.tex 2011/03/14 15:01:28 1.10 +++ manual/s_phys_pkgs/text/obcs.tex 2011/03/16 10:39:25 1.11 @@ -400,21 +400,21 @@ how the net inflow is redistributed as small correction velocities between the individual sections. A value ``\code{-1}'' balances an individual boundary, values $>0$ determine the relative size of the -correction. For example, with the values +correction. For example, the values \begin{tabbing} - \code{OBCS\_balanceFac\_E}\=\code{ = 1.,} \\ - \code{OBCS\_balanceFac\_W}\>\code{ = -1.,} \\ - \code{OBCS\_balanceFac\_N}\>\code{ = 2.,} \\ - \code{OBCS\_balanceFac\_S}\>\code{ = 0.,} + \code{OBCS\_balanceFacE}\code{ = 1.,} \\ + \code{OBCS\_balanceFacW}\code{ = -1.,} \\ + \code{OBCS\_balanceFacN}\code{ = 2.,} \\ + \code{OBCS\_balanceFacS}\code{ = 0.,} \end{tabbing} -will make the model +make the model \begin{itemize} \item correct Western \code{OBWu} by substracting a uniform velocity to -ensure zero net transport through Western OB +ensure zero net transport through the Western open boundary; \item correct Eastern and Northern normal flow, with the Northern - velocity correction two times larger than Eastern correction, but - not the Southern normal flow to ensure that the total inflow through - East, Northern, and Southern OB is balanced + velocity correction two times larger than the Eastern correction, but + \emph{not} the Southern normal flow, to ensure that the total inflow through + East, Northern, and Southern open boundary is balanced. \end{itemize} The old method of balancing the net flow for all sections individually @@ -427,13 +427,13 @@ u(y,z) - \int_{\mbox{western boundary}}u\,dy\,dz \approx OBNu(j,k) - \sum_{j,k} OBNu(j,k) h_{w}(i_{b},j,k)\Delta{y_G(i_{b},j)}\Delta{z(k)}. \] -This also ensures a net total inflow of zero through all boundaries to -make it a useful flag for preventing infinite sea-level change within -the domain, but this combination of flags is \emph{not} useful if you -want to simulate, say, a sector of the Southern Ocean with a strong -ACC entering through the western and leaving through the eastern -boundary, because the value of ``\code{-1}'' for these flags will make -sure that the strong inflow is removed. +This also ensures a net total inflow of zero through all boundaries, +but this combination of flags is \emph{not} useful if you want to +simulate, say, a sector of the Southern Ocean with a strong ACC +entering through the western and leaving through the eastern boundary, +because the value of ``\code{-1}'' for these flags will make sure that +the strong inflow is removed. Clearly, gobal balancing with +\code{OBCS\_balanceFacE/W/N/S} $\ge0$ is the preferred method. \paragraph{OBCS\_APPLY\_*:} ~ \\ ~ @@ -455,7 +455,7 @@ where $\chi$ is the model variable (U/V/T/S) in the interior, $\chi_{BC}$ the boundary value, $L$ the thickness of the sponge layer (runtime parameter \code{spongeThickness} in number of grid points), -$\delta{L}\in[0,L]$ ($l\in[0,1]$) the distance from the boundary (also in grid points), and +$\delta{L}\in[0,L]$ ($\frac{\delta{L}}{L}=l\in[0,1]$) the distance from the boundary (also in grid points), and $\tau_{b}$ (runtime parameters \code{Urelaxobcsbound} and \code{Vrelaxobcsbound}) and $\tau_{i}$ (runtime parameters \code{Urelaxobcsinner} and \code{Vrelaxobcsinner}) the relaxation time