%$Id: exercise_topography.tex 974 2012-08-08 09:34:21Z gryschka $ \input{header_tmp.tex} %\input{../header_lectures.tex} \usepackage[utf8]{inputenc} \usepackage{ngerman} \usepackage{pgf} \usetheme{Dresden} \usepackage{subfigure} \usepackage{units} \usepackage{multimedia} \usepackage{hyperref} \newcommand{\event}[1]{\newcommand{\eventname}{#1}} \usepackage{xmpmulti} \usepackage{tikz} \usetikzlibrary{shapes,arrows,positioning,decorations.pathreplacing} \def\Tiny{\fontsize{4pt}{4pt}\selectfont} %---------- neue Pakete \usepackage{amsmath} \usepackage{amssymb} \usepackage{multicol} \usepackage{pdfcomment} \usepackage{xcolor} \institute{Institut für Meteorologie und Klimatologie, Leibniz Universität Hannover} \date{last update: \today} \event{PALM Seminar} \setbeamertemplate{navigation symbols}{} \setbeamersize{text margin left=.5cm,text margin right=.2cm} \setbeamertemplate{footline} {% \begin{beamercolorbox}[rightskip=-0.1cm]& {\includegraphics[height=0.65cm]{imuk_logo.pdf}\hfill \includegraphics[height=0.65cm]{luh_logo.pdf}} \end{beamercolorbox} \begin{beamercolorbox}[ht=2.5ex,dp=1.125ex,% leftskip=.3cm,rightskip=0.3cm plus1fil]{title in head/foot}% {\leavevmode{\usebeamerfont{author in head/foot}\insertshortauthor} \hfill \eventname \hfill \insertframenumber \; / \inserttotalframenumber}% \end{beamercolorbox}% % \begin{beamercolorbox}[colsep=1.5pt]{lower separation line foot}% % \end{beamercolorbox} }%\logo{\includegraphics[width=0.3\textwidth]{luhimuk_logo.eps}} \title[Exercise - Topography]{Exercise - Topography} \author{Siegfried Raasch} % Notes: % jede subsection bekommt einen punkt im menu (vertikal ausgerichtet. % jeder frame in einer subsection bekommt einen punkt (horizontal ausgerichtet) \begin{document} % Folie 1 \begin{frame} \titlepage \end{frame} \section{Exercise} \subsection{Exercise} % Folie 2 \begin{frame} \frametitle{Exercise} Please carry out \textbf{two runs} with following conditions. \begin{itemize} \item{Single surface-mounted cube} \begin{itemize} \item[1.)]{First run ''generic'' using {\tt topography = 'single\_building'}} \item[2.)]{Second run ''raster'' using {\tt topography = 'read\_from\_file'} with ASCII file ...\_topo} \end{itemize} \item{Neutral boundary layer in a channel} \item{Constant bulk velocity} \item{No Coriolis force} \item{Simulation features:} \begin{itemize} \item{domain size: (80 m)$^3$ (x/y/z)} \item{grid size: 2 m equidistant} \item{cube: size (40 m)$^3$, location centered in the domain center} \item{simulated time: 7200 s} \item{initial velocity: u = 1, v = 0 m/s} \end{itemize} \end{itemize} \textbf{Please use the same building (size, location) for both runs!} \end{frame} % Folie 3 \begin{frame} \frametitle{Questions to be Answered} \small \begin{itemize} \item{Can you identify flow convergence / divergence patterns near the cube?} \begin{itemize} \item{What kind of output do you need to answer this?} \end{itemize} \item{How does the horizontally and temporally averaged momentum flux profile look like?} \begin{itemize} \item{How long should the averaging time interval be?} \end{itemize} \item{Is it really a large-eddy simulation?} \begin{itemize} \item{Are the subgrid-scale fluxes much smaller than the resolved-scale fluxes?} \item{How do the total kinetic energy and the maximum velocity components change with time?} \end{itemize} \end{itemize} \textbf{Final question:} \begin{itemize} \item{Do the results of both runs agree?} \end{itemize} \end{frame} % Folie 4 \begin{frame} \frametitle{Hints (I)} \scriptsize \begin{itemize} \item{\textbf{Domain size}} \begin{itemize} \scriptsize \item{Is controlled by grid size (\textbf{dx}, \textbf{dy}, \textbf{dz}) and number of grid points (\textbf{nx}, \textbf{ny}, \textbf{nz}). Since the first grid point along one of the directions has index 0, the total number of grid points used are \textbf{nx}+1, \textbf{ny}+1, \textbf{nz}+1. The total domain size in case of cyclic horizontal boundary conditions is (\textbf{nx}+1)$\cdot$\textbf{dx}, (\textbf{ny}+1)$\cdot$\textbf{dy}.} \end{itemize} \item{\textbf{Initial profiles}} \begin{itemize} \scriptsize \item{Constant with height. See parameter \textbf{initializing\_actions} for available initialization methods. See \textbf{ug\_surface}, \textbf{vg\_surface} for initial values of velocity.} \end{itemize} \item{\textbf{Boundary conditions}} \begin{itemize} \scriptsize \item{For channel boundary condition, see \textbf{bc\_uv\_t}.} \end{itemize} \item{\textbf{Forcing}} \begin{itemize} \scriptsize \item{For constant bulk velocity, see \textbf{conserve\_volume\_flow}.} \item{For Coriolis force, see \textbf{omega}.} \end{itemize} \item{\textbf{Topography}} \begin{itemize} \scriptsize \item{For generic topography, see \textbf{building\_height}, \textbf{building\_length\_x} and \textbf{building\_length\_y}.} \item{For raster topography, please use a text editor to manually create an ASCII ''raster\_topo'' file that contains the same building.} \end{itemize} \end{itemize} \end{frame} % Folie 5 \begin{frame} \frametitle{Hints (II)} \footnotesize \begin{itemize} \item{\textbf{Simulation time}} \begin{itemize} \footnotesize \item{See parameter \textbf{end\_time}.} \end{itemize} \item{\textbf{Variables}} \begin{itemize} \footnotesize \item{Output variables are chosen with parameters \textbf{data\_output} (3d-data or 2d-cross-sections) and \textbf{data\_output\_pr} (profiles).} \item{Time series are activated using \textbf{dt\_dots}.} \end{itemize} \item{\textbf{Output intervals}} \begin{itemize} \footnotesize \item{Output intervals are set with parameter \textbf{dt\_data\_output}. This parameter affects all output (cross-sections, profiles, etc.). Individual temporal intervals for the different output quantities can be assigned using parameters \textbf{dt\_do3d}, \textbf{dt\_do2d\_xy}, \textbf{dt\_do2d\_xz}, \textbf{dt\_do2d\_yz}, \textbf{dt\_dopr}, etc. } \end{itemize} \item{\textbf{Time averaging}} \begin{itemize} \footnotesize \item{Time averaging is controlled with parameters \textbf{averaging\_interval}, \textbf{averaging\_interval\_pr}, \textbf{dt\_averaging\_input}, \textbf{dt\_averaging\_input\_pr}.} \end{itemize} \end{itemize} \end{frame} % Folie 6 \begin{frame} \frametitle{Further Hints} \scriptsize Please see under \\ \textbf{http://palm.muk.uni-hannover.de/wiki/doc/app/netcdf} \\ \par\medskip where the complete PALM netCDF-data-output and the respective steering parameters are described. \par\medskip For topography, see \\ \textbf{http://www.muk.uni-hannover.de/$\sim$raasch/PALM\_group/doc/app/ chapter\_4.1.html\#topography}\\ \par\medskip and especially for raster topography, see also \textbf{http://www.muk.uni-hannover.de/$\sim$raasch/PALM\_group/doc/app/ chapter\_3.4.html\#TOPOGRAPHY\_DATA} \\ \par\medskip as well as the presentation ''Using topography (I)''. \end{frame} % Folie 7 \begin{frame} \frametitle{Proceeding} Please proceed as follows: \begin{itemize} \item[1.]{Please run with the ''generic'' topography case first.} \item[2.]{Check your results to answer all questions – except the final question.} \item[3.]{After this run has finished, use ncview, ncdump etc. to check the precise location of the building (look at 2D array zusi that is contained in 2D xy cross-sections and 3D volume data).} \item[4.]{Use this information to manually create the ''raster\_topo'' file.} \item[5.]{Run the ''raster'' topography case.} \item[6.]{Compare both simulation results to answer the final question.} \end{itemize} \end{frame} % Folie 8 \begin{frame} \frametitle{How to Start?} \footnotesize \begin{itemize} \item{Create two \textbf{INPUT} directories for both new runs: \\ {\tt cd $\sim$/palm/current\_version} \\ {\tt mkdir -p JOBS/generic/INPUT} \\ {\tt mkdir -p JOBS/raster/INPUT}} \item{Create the parameter files and {\tt raster\_topo} file and set the required parameters in \\ {\tt JOBS/generic/INPUT/generic\_p3d} \\ {\tt JOBS/raster/INPUT/raster\_p3d}} \item{Start the runs one by one with mrun-commands \\ {\tt mrun -d generic -K parallel ...} \\ {\tt mrun -d raster -K parallel ...}} \item{and analyze the output files in \\ {\tt JOBS/generic/OUTPUT} \\ {\tt JOBS/raster/OUTPUT}} \end{itemize} \end{frame} \section{Results} \subsection{Results} % Folie 9 \begin{frame} \frametitle{Flow convergence / divergence (I)} \includegraphics[width=0.45\textwidth]{exercise_topography_figures/cross_sections/u_xy.eps} \hspace{0.8cm} \includegraphics[width=0.45\textwidth]{exercise_topography_figures/cross_sections/v_xy.eps} \end{frame} % Folie 10 \begin{frame} \frametitle{Flow convergence / divergence (II)} \includegraphics[width=0.45\textwidth]{exercise_topography_figures/cross_sections/w_xy.eps} \hspace{0.8cm} \includegraphics[width=0.45\textwidth]{exercise_topography_figures/cross_sections/w_xz.eps} \end{frame} % Folie 11 \begin{frame} \frametitle{Streamlines} \includegraphics[width=0.45\textwidth]{exercise_topography_figures/streamlines/streamlines_xy.eps} \hspace{0.8cm} \includegraphics[width=0.45\textwidth]{exercise_topography_figures/streamlines/streamlines_xz.eps} \hspace{0.8cm} \end{frame} % Folie 12 \begin{frame} \frametitle{Vertical profiles of $\overline{w'u'}$, $\overline{w'v'}$} \includegraphics[width=0.45\textwidth]{exercise_topography_figures/profiles/wu_time_pr.eps} \hspace{0.8cm} \includegraphics[width=0.45\textwidth]{exercise_topography_figures/profiles/wv_time_pr.eps} \end{frame} % Folie 13 \begin{frame} \frametitle{LES? - Fluxes} \begin{center} \includegraphics[width=0.6\textwidth]{exercise_topography_figures/profiles/wu_comp_pr.eps} \end{center} \end{frame} % Folie 14 \begin{frame} \frametitle{LES? - Time Series (I)} \begin{center} \includegraphics[width=0.95\textwidth]{exercise_topography_figures/timeseries/E_ts.eps} \\ \includegraphics[width=0.95\textwidth]{exercise_topography_figures/timeseries/umax_ts.eps} \end{center} \end{frame} % Folie 15 \begin{frame} \frametitle{LES? - Time Series (II)} \begin{center} \includegraphics[width=\textwidth]{exercise_topography_figures/timeseries/vmax_ts.eps} \\ \includegraphics[width=\textwidth]{exercise_topography_figures/timeseries/wmax_ts.eps} \end{center} \end{frame} \end{document}