\documentclass[border=5pt]{standalone}
%%%<
\usepackage{verbatim}
%%%>
\usepackage{pgfplots}
\pgfplotsset{width=7cm,compat=1.8}
\begin{comment}
:Title: Streamline data
:Tags: 2D;
:Author: Paul Gessler
:Slug: streamline-data

I enjoy the simplicity of the code and the quality of the result. It uses
pgfplots to display streamline data for vortex shedding from a square block
at Re=100. The streamline data were computed by a Fortran code I wrote to
model the flow.

The data files are quite large; they are available here for anyone wishing
to reproduce my result. The full paper is available for download on:
https://dl.dropboxusercontent.com/u/10724484/TeX.SX/StreamlineData.zip
It includes many similar figures showing different times during the vortex
shedding process.

Paul Gessler on TeX.SE
\end{comment}

\begin{document}
\begin{tikzpicture}
\begin{axis}[
  axis equal image,
  xmin=13,xmax=35,
  ymin=0,ymax=3,
  width=7in,
  xlabel={$x/D$ (-)},
  ylabel={$y/D$ (-)},
]
  \foreach \num in {1,2,...,18} {
    \addplot[black] file {time43.39stream\num.dat};                          
  }
  \draw[fill=black] (axis cs:15,1) rectangle (axis cs:16,2);
\end{axis}
\end{tikzpicture}
\end{document}
