Interpreting the cosmological constant as a pressure, whose thermodynamically conjugate variable is a volume, modifies the first law of black hole thermodynamics. Properties of the resulting thermodynamic volume are investigated: the compressibility and the speed of sound of the black hole are derived in the case of non-positive cosmological constant. The adiabatic compressibility vanishes for ...

In this paper, the laminar incompressible flow equations are solved by an upwind least-squares meshless method. Due to the difficulties in generating quality meshes, particularly in complex geometries, a meshless method is increasingly used as a new numerical tool. The meshless methods only use clouds of nodes to influence the domain of every node. Thus, they do not require the nodes to be conn...

In this paper, results of a free sorting task of 124 different material samples are analysed using multidimensional scaling. The relevant number of dimensions for haptic perception of materials is estimated to be 4. In addition, the haptic material space is calibrated by means of physical measurements of compressibility and roughness. The relation between objective and perceived compressibility...

Total compressibility in a fractured reservoir is estimated using the pressure response due to gravitational potential variations. Both the lunar and the solar gravitational potentials are fully accounted for by inclusion of longer-period components. The semidiurnal and diurnal pressure data show substantial long-term variations. The gravitational potential also contains the same variation tren...

This paper presents the initial stage of an effort aimed at developing a new correlation to estimate pseudo critical properties for sour gas when the exact composition is not known. Several mixing rules and gas gravity correlations available in the literature are first evaluated and compared. The evaluation is performed on a large database consisting of more than 2000 samples of sour gas compos...

Drag reduction by bubbles in stationary turbulent flows is sensitive to the compressibility of the bubbles. Without this dynamical effect the bubbles only renormalize the fluid density and viscosity, an effect that by itself can only lead to a small percentage of drag reduction. We show in this paper that the dynamics of bubbles and their effect on the compressibility of the mixture can lead to...

A nonequilibrium statistical operator method is developed for ensembles of particles obeying non-Hamiltonian equations of motion in classical phase space. The main consequences of non-zero compressibility of phase space are examined in terms of time-dependent dynamic quantities. The generalized transport equations involve the phase-space compressibility in a non-trivial way. Our results are use...

The role of negative compressibility is considered in detail. Experimental observations of negative bulk modulus in prestrained foam are presented and interpreted. A constrained microscopic model which exhibits negative compressibility is proposed. Some other negative and counterintuitive properties of matter, like negative Poisson’s ratio, negative thermal expansion, negative specific heat, an...

In this paper, an HLLC-type contact preserving Riemann solver for incompressible two-phase flows using the artificial compressibility formulation is presented. This improvement over previous HLLC-VOF (Bhat and Mandal, 2019). work, unlike formulation, variation of volume fraction taken into account when calculating eigenvalues eigenvectors. Hence, equations intermediate states wave speed are clo...

The compression of a crystalline material under hydrostatic pressure always results in a reduction in volume of the solid, with the observed reduction typically occurring in all crystallographic cell parameters. However, there are a number of exceptional materials that have been shown to expand in a specific direction upon hydrostatic compression while maintaining a positive volume compression....