Joule-Thomson expansion of Einstein-Skyrmion black holes

The Joule-Thomson expansion of Einstein-Skyrmion black holes in four dimensions was studied in the extended phase space. We obtained the inversion curves and isenthalpic curves for different values of parameters K and a, which represent the coupling strength between the gravity field and matter field. We found that parameters K and a have the same effects during the entire Joule-Thomson expansion and larger parameter K or a corresponds to smaller inversion pressure. Analogously, the phase space {T, P} consists of cooling-heating regions. In addition, the dispersion point of the Joule-Thomson coefficient mu is in correspondence with the zero point of the Hawking temperature T, and the ratio of the minimum inversion temperature Tmin i and the critical temperature Tc is a constant.