Erratum: Hu et al. Numerical Investigation of Flow and Heat Transfer in a Rotor-Stator Cavity with Centripetal Carbon Dioxide Through-Flow. Energies 2019, 12, 2613

The authors would like to make the following explanations and changes to the original paper [1]:

• The University Duisburg-Essen (Professor Brillert) grants permission to Dr. Hu to use the geometry of the large test rig for the numerical investigation only. Table 1 describes in fact exactly the geometry of the back chamber of the original Duisburg rig.
• In the first paragraph in the chapter “Rotor-Stator Cavity Test Rig”, we agree to add the sentence” which describes exactly the geometry of the back chamber of the original Duisburg rig [1]. ”
• The geometries in Table 1 are made non-dimensional as follows:

  Table 1. Main parameters of the test zone in this study.

  ${\mathit{r}}_{\mathit{o}}/\mathit{b}$	$\mathit{s}/\mathit{b}$	${\mathit{s}}_{\mathit{b}}/\mathit{b}$	$\mathbf{\Delta }\mathit{r}/\mathit{b}$	${\mathit{s}}_{\mathit{o}}/\mathit{b}$
  0.175	0.0125, 0.0375	0.0375	0.005	0.005

  Table 1. Main parameters of the test zone in this study.

  ${\mathit{r}}_{\mathit{o}}/\mathit{b}$	$\mathit{s}/\mathit{b}$	${\mathit{s}}_{\mathit{b}}/\mathit{b}$	$\mathbf{\Delta }\mathit{r}/\mathit{b}$	${\mathit{s}}_{\mathit{o}}/\mathit{b}$
  0.175	0.0125, 0.0375	0.0375	0.005	0.005

• By mutual agreement, the authors would like to remove the names of Yanxia Fu and Chunwei Gu from the author’s list; the authors’ contribution is reformulated as follows:
  B.H. and X.R. wrote the paper. B.H. conducted the numerical simulations; B.H. and J.L. analyzed the results. X.L. acted as the Principal Investigator of the research that funded the study.
• The authors acknowledge that some numerical simulations were conducted at University of Duisburg-Essen [2]. The geometry of the back chamber is the very same as the one described in Ref. [1], which is built at the University of Duisburg-Essen. The experimental results were obtained by T.R. Schroeder at Duisburg-Essen and were later analyzed by Bo Hu. When in Duisburg, Dr. Hu only contributed to the small test rig experiments, and he legally gained knowledge about the large rig and the experiments while working as a Doctoral student at the University of Duisburg-Essen.
• The experimental results were not obtained at the Tsinghua University, and they are published only (Figure 7) to provide a better description of the numerical simulations. A proper acknowledgement has been added to Figure 7.
• The results of the numerical simulations were shared between Tsinghua University and University of Duisburg-Essen.