% test-shared-inflow.tex — Forrester diagram with one shared inflow
% valve feeding two stocks side by side.  The aux R is the rate that
% fills both reservoirs Va and Vb; the renderer places R, Va, Vb on
% one row and draws a straight flow into Va with a curved branch
% over Va into Vb.
%
% Variable identifiers are letter-only (TeX control-word constraint)
% but the display texts use the conventional V_1 / V_2 subscripts.

\documentclass{article}
\usepackage{numodel}

\begin{document}

\newmodelprefix{share}

\mvar{T}{t}{0}{\s}{2}{system}
\mvar{Dt}{dt}{0.1}{\s}{1}{system}
\mvar{R}{r}{5}{\m\cubed\per\s}{2}{aux}
\mvar{Va}{V_1}{0}{\m\cubed}{3}{stock}
\mvar{Vb}{V_2}{0}{\m\cubed}{3}{stock}

\mrule{R}{5}
\mrule{Va}{\shareVa + \shareR * \shareDt}
\mrule{Vb}{\shareVb + \shareR * \shareDt}
\mrule{T}{\shareT + \shareDt}
\mstop{\shareT >= 5}

\section*{Tekstmodel}
\textmodel

\section*{Grafisch model (gedeelde instroom $R$ voor $V_1$ en $V_2$)}
\graphicmodel

\end{document}