Joule-Thomson expansion of the regular(Bardeen)-AdS black hole * * Supported by the Program for NCET-12-1060, by the Sichuan Youth Science and Technology Foundation (2011JQ0019), and by FANEDD (201319), and by Ten Thousand Talent Program of Sichuan Province, and by Sichuan Natural Science Foundation (16ZB0178), and by the starting funds of China West Normal University (17YC513, 17C050)

Abstract

We study the Joule-Thomson expansion of the regular black hole in an anti-de Sitter background, and obtain the inversion temperature for the Bardeen-AdS black hole in the extended phase space. We investigate the isenthalpic and inversion curves for the Bardeen-AdS black hole in the T-P plane and find that the intersection points between them are exactly the inversion points discriminating the heating from the cooling process. The inversion curve for the regular(Bardeen)-AdS black hole is not closed and there is only a lower inversion curve, in contrast to the Van der Waals fluid. Most importantly, we find that the ratio between the minimum inversion temperature and the critical temperature for the regular(Bardeen)-AdS black hole is 0.536622, which is larger than any known ratio for the singular black hole. The large ratio for the Bardeen-AdS black hole may be due to the repulsive de Sitter core near the origin of the regular black hole.