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arXiv · 1905.02318

Joule-Thomson expansion for the regular(Bardeen)-AdS black hole

Jin Pu·Sen Guo·Qing-Quan Jiang·Xiao-Tao Zu
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Abstract

In this paper, we attempt to study the Joule-Thomson expansion for the regular black hole in an anti-de Sitter background, and obtain the inversion temperature and curve 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 to find the intersection points between them are exactly the inversion points discriminating the heating process from the cooling one. And, the inversion curve for the regular(Bardeen)-AdS black hole is not closed and there is only a lower inversion curve in contrast with that of the Van der Walls fluid. Most importantly, we find the ratio between the minimum inversion and critical temperature for the regular(Bardeen)-AdS black hole is 0.536622, which is always larger than all the already-known ratios for the singular black hole. This larger ratio for the Bardeen-AdS black hole in contrast with the singular black hole may stem from the fact that there is a repulsive de Sitter core near the origin of the regular black hole.

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Jin Pu, Sen Guo, Qing-Quan Jiang, Xiao-Tao Zu. 2019-07-18. Joule-Thomson expansion for the regular(Bardeen)-AdS black hole. https://doi.org/10.1088/1674-1137%2F44%2F3%2F035102

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