\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={$T/\si{\kelvin}$},
    grid=both,
    title={TS background families and process paths}
  ]
    \LCPAddTSPlots[
      fluid=R134a,
      isenthalp=true,
      quality step=0.2,
      enthalpy values={200,250,300,350,400,450},
      labels=false
    ]
    \LCPAddTSProcess[
      fluid=R134a,
      type=isobar,
      from={p=2bar,Q=0},
      to={p=2bar,Q=1},
      color=black,
      label={evaporation},
      mark endpoints=true,
      export coordinates=DemoTS,
      log coordinates=true
    ]
    \LCPAddTSProcess[
      fluid=R134a,
      type=isentropic,
      from={p=2bar,Q=1},
      to={p=12bar,s=\DemoTSToEntropySI},
      color=purple,
      label={compression}
    ]
  \end{axis}
\end{tikzpicture}
\end{document}

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