We have performed direct numerical simulations (DNS) of compressible turbulent channel flow at supercritical pressure with top and bottom isothermal walls kept respectively at a supercritical (T top > T pb ) and subcritical temperature (T bot < T pb ), where T pb is the pseudoboiling temperature. The DNS are conducted using a high-order discretization of the fully compressible Navier-Stokes equations in conservative form closed with the Peng-Robinsion (PR) state equation. Bulk density is adjusted to obtain a bulk pressure of approximately p b = 1.1p cr where p cr is the critical pressure of the working fluid. Top-to-bottom temperature differences investigated are ∆T = 5 K, 10 K, and 20 K, where T top/bot = T pb ± ∆T /2; buoyancy effects are neglected. Varying ∆T modifies the average location of pseudophase change from y pb /h = −0.23 (∆T = 5 K) to 0.89 (∆T = 20 K), where h is the channel half-height and y = 0 the centerline position. Real-fluid effects cause visible deviations from classical scaling laws in the mean velocity profile. Enstrophy generation due stretching and tilting decreases with ∆T . The proximity to the pseudotransitioning layer inhibits the intensity of the velocity fluctuations, while enhancing the density and temperature fluctuations. Conditional probability analysis reveals that the sheet of fluid undergoing pseudophase change is characterized by a dramatic reduction in the kurtosis of density fluctuations and becomes thinner as ∆T is increased. Instantaneous visualizations show dense fluid ejections from the pseudoliquid viscous sublayer, some reaching the channel core, causing positive values of density skewness in the respective buffer-layer region (vice versa for the top wall).

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Queen Min (1851-1895) is described in numerous texts including diaries and newspaper articles written by Western, Japanese and Korean authors who lived in Korea between the late 19th and early 20th centuries. However, she is without visual identity, i.e., facial identity, even though King Kojong (1864-1907) referred to the existence of a portrait. This article holds that visual and non-visual identities are complementary to a person. It argues that in the case of Queen Min, the missing visual record generates a de-personification of her identity and that this contributes to the tarnishing of her public and private role in the period prior to Japan’s annexation of Korea. The paper also discusses the history of the queen’s visual identity, which is missing from official history, and inquires into its significance.

The development of a simple and efficient methodologies for numerically analyzing the material fracture process is very important in the field of computational mechanics. Damage mechanics approaches are still applied to fracture numerical analyses of many engineering practice problems. This paper focuses on the numerical prediction of crack propagation and fracture behavior by the combination of anisotropic damage model and tracking algorithm. In general, anisotropic damage models may be misunderstood to be used only in the simulations of anisotropic materials. However, it can be used for the anisotropic stiffness matrix induced by the crack plane in damaged isotropic materials. Although it is well known that the anisotropic damage model is superior to the isotropic damage model in fracture simulations, most of studies have combined the isotropic damage model and tracking algorithm, and few studies combine the anisotropic damage model and tracking algorithm. The issues of successfully combining the anisotropic damage model and crack tracking algorithm are addressed in this study. The anisotropic damage model is improved and a local tracking algorithm based on crack surface discretization is also modified. Various crack propagation problems are analyzed numerically to demonstrate the superior performance of the proposed approach.