Shock–multicloud interactions in galactic outflows – II. Radiative fractal clouds and cold gas thermodynamics

Galactic winds are crucial to the cosmic cycle of matter, transporting material out dense regions galaxies. Observations show coexistence different temperature phases in such winds, which is not easy explain. We present a set 3D shock-multicloud simulations that account for radiative heating and cooling at temperatures between $10^2\,\rm K$ $10^7\,\rm K$. The interplay shock heating, dynamical instabilities, turbulence, creates complex multi-phase flow with rain-like morphology. Cloud gas fragments continuously eroded, becoming efficiently mixed mass loaded. resulting warm then cools down precipitates into new cloudlets, repeat process. Thus, able sustain fast-moving by aiding condensation from clouds hot wind. In ensuing outflow, $\gtrsim 10^6\,\rm outruns cold phases, reach thermal equilibrium near $\approx 10^4\,\rm 10^2\,\rm K$, respectively. Although volume filling factor higher most concentrated cloudlets filaments these temperatures. More porous multicloud layers result more vertically extended outflows, produced compact layers. phase accelerated ram-pressure, but, instead, equilibrium. This can explain presence high-velocity H\,{\sc i} $N_{\rm H\,{\scriptstyle I}}=10^{19-21}\,\rm cm^{-2}$ $\Delta v_{{\rm FWHM}}\lesssim37\,\rm km\,s^{-1}$ centre outflow.