\documentclass[tikz,border=6pt]{standalone}
\usepackage{luacoolprop}
\pgfplotsset{compat=1.18}

\begin{document}
\begin{tikzpicture}
  \begin{axis}[
    width=13cm,
    height=8cm,
    xlabel={$s/\si{\kilo\joule\per\kilogram\per\kelvin}$},
    ylabel={$h/\si{\kilo\joule\per\kilogram}$},
    grid=both,
    title={Water HS background and process paths}
  ]
    \LCPAddHSPlots[
      fluid=Water,
      pressure min=10000,
      pressure max=30000000,
      quality step=0.2,
      isobar=true,
      isobar values={0.1,1,10,100},
      isobar temperature min=10,
      isobar temperature max=500,
      labels=false
    ]
    \LCPAddHSProcess[
      fluid=Water,
      type=isobar,
      from={p=1bar,Q=0},
      to={p=1bar,Q=1},
      color=black,
      label={evaporation},
      mark endpoints=true,
      export coordinates=DemoHS,
      log coordinates=true
    ]
    \LCPAddHSProcess[
      fluid=Water,
      type=isentropic,
      from={p=1bar,Q=1},
      to={p=10bar,s=\DemoHSToEntropySI},
      color=purple,
      label={isentropic compression}
    ]
  \end{axis}
\end{tikzpicture}
\end{document}

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