相关论文: Speed of sound in liquids at high pressure
Dispersion of collective excitations in fluid Hydrogen along the isothermal line T=2500~K, including the region of molecular-to-atomis fluid transition, is studied by ab initio molecular dynamics (AIMD) simulations. The obtained density…
Motivated by recent experiments in Phys. Rev. Lett. 121, 145301 (2018), we study sound propagation in a two-dimensional (2D) Bose gas across the superfluid-thermal transition using classical field dynamics. Below the transition temperature…
We study a model of flocking for a very large system (N=320,000) numerically. We find that in the long wavelength, long time limit, the fluctuations of the velocity and density fields are carried by propagating sound modes, whose dispersion…
We sketch an algorithm to generate exact anisotropic solutions starting from a barotropic EoS and setting an ansatz on the metric functions. To illustrate the method, we use a generalization of the polytropic equation of state consisting of…
We propose an improved model explaining the occurrence of high stresses due to the difference in specific volumes during phase transitions between water and ice. The unknowns of the resulting evolution problem are the absolute temperature,…
The quantum speed limit specifies a universal bound of the fidelity between the initial state and the time-evolved state. We apply this method to find a bound of the fidelity between the adiabatic state and the time-evolved state. The bound…
The Hagedorn temperature, T_H is determined from the number of hadronic resonances including all mesons and baryons. This leads to a stable result T_H = 174 MeV consistent with the critical and the chemical freeze-out temperatures at zero…
Acoustic material parameters of gas hydrate bearing porous rocks are important for evaluation of methods to exploit the vast methane gas resources present in the earth's subsurface, potentially combined with CO2 injection. A solid buffer…
The bubble nucleation in superheated liquid can be controlled by adjusting the ambient pressure and temperature. At higher pressure the threshold energy for bubble nucleation increases and we have observed that the amplitude of the acoustic…
A reliable model of viscosity in liquids using a dual liquid model framework is developed. The analytical expression arrived at exhibits the correct T-dependence Arrhenius-like. It is compared with the values of viscosity for water with…
We describe an experimental setup specifically designed for measuring the ultrasonic transmission through liquid foams, over a broad range of frequencies (60-600 kHz). The question of determining the ultrasonic properties of the foam…
The validity of the anelastic approximation has recently been questioned in the regime of rapidly-rotating compressible convection in low Prandtl number fluids (Calkins et al. 2015). Given the broad usage and the high computational…
Pressure changes travel at an infinite sound speed in an incompressible ideal fluid, opposite to what happens in a bubbly liquid, where the presence of bubbles adds compressibility such that the sound speed becomes finite. Here, the…
A simple and popular Bridgman's formula predicts a linear correlation between the thermal conductivity coefficient and the sound velocity of dense liquids. Unfortunately, it cannot be applied to strongly coupled plasma-related fluids,…
In this work, the normal density $\rho_n$ and moment of inertia of a moving superfluid are investigated. We find that, even at zero temperature, there exists a finite normal density for the moving superfluid. When the velocity of superfluid…
A molecular dynamics (MD) simulation was performed to study the propagation of soundwaves in a fluid. Soundwaves are generated by a sinusoidally oscillating wall and annihilated by a locally applied Langevin thermostat near the opposite…
We consider an ideal Fermi gas of tachyonic thermal excitations as a continuous medium and establish when it satisfies the causality condition. At high temperature the sound speed is always subluminal $c_s<1$, but there is no stable form of…
A simple and popular Bridgman's model predicts a linear correlation between the thermal conductivity coefficient and the sound velocity of dense liquids. A proportionality coefficient proposed originally is fixed and independent of the…
The rise in temperature from the adiabatic compression of a bubble is computed in thermodynamic mean field (van der Waals) theory. It is shown that the temperature rise is higher for the noble gas atoms than for more complex gas molecules.…
Sound velocities of vitreous silica are measured under He compression in the pressure range 0-6 GPa by Brillouin light scattering. It is found that the well-known anomalous maximum in the pressure dependence of the compressibility is…