Commit a1b2566b by Olivier

 \renewcommand{\lastedityear}{2018} \renewcommand{\lasteditmonth}{06} \renewcommand{\lasteditday}{08} \renewcommand{\lasteditday}{12} \renewcommand{\numberofthischapter}{8} \renewcommand{\titleofthischapter}{\namechaptereight} \atstartofexercises ... ... @@ -78,7 +78,14 @@ In homogeneous, isotropic, fully-developed turbulence, we accept the following r \subsubsection{Cumulus cloud} \wherefrom{Non-examinable. From Tennekes \& Lumley \cite{tennekesetal1972} P1.1} A cumulus cloud (one of those “fluffy” summer clouds) has roughly the size of a sphere of diameter $D = \SI{50}{\meter}$. To a good approximation, it features isotropic, homogeneous, fully-developed turbulence. The largest-scale air currents in the cloud reach a maximum velocity $V = \SI{3}{\metre\per\second}$. A cumulus cloud (one of those “fluffy” summer clouds, figure~\ref{fig_fluffy_cloud}) has roughly the size of a sphere of diameter $D = \SI{50}{\meter}$. To a good approximation, it features isotropic, homogeneous, fully-developed turbulence. The largest-scale air currents in the cloud reach a maximum velocity $V = \SI{3}{\metre\per\second}$. \begin{figure}[ht] \begin{center} \includegraphics[width=0.3\textwidth]{Bluesky.jpg} \end{center} \supercaption{Summer clouds (\textit{Cumulus humilis}) form when hot moist air convected from the ground is cooled down when it rises.}{\wcfile{Bluesky.jpg}{Photo} \ccbysa by \weu{Dwindrim}} \label{fig_fluffy_cloud} \end{figure} \begin{enumerate} \item What is approximately the size of the smallest eddies in the cloud? \item What is approximately the dissipation power, per unit mass of air and for the entire cloud? ... ... @@ -88,7 +95,14 @@ In homogeneous, isotropic, fully-developed turbulence, we accept the following r \subsubsection{Reactor tank} \wherefrom{Non-examinable. \cczero \oc} A tank used to store chemical reactants has roughly the size of a cube of side length $L = \SI{2}{\metre}$. The tank is filled with a water-like liquid and vigorously stirred with a large agitator propeller for a prolonged amount of time. The propeller induces a maximum fluid velocity of \SI{1,5}{\metre\per\second}. A tank used to store chemical reactants has roughly the size of a cube of side length $L = \SI{2}{\metre}$ (figure~\ref{fig_tank_agitator}). The tank is filled with a water-like liquid and vigorously stirred with a large agitator propeller for a prolonged amount of time. The propeller induces a maximum fluid velocity of \SI{1,5}{\metre\per\second}. \begin{figure}[ht] \begin{center} \includegraphics[width=0.3\textwidth]{tank_agitator} \end{center} \supercaption{Schematic drawing of a cubic tank stirred with an agitator propeller}{Figure \cczero \oc} \label{fig_tank_agitator} \end{figure} \begin{enumerate} \item What is approximately the size of the smallest eddies in the tank? \item What is approximately the specific dissipation power? ... ...