Generalized potentials for a mean-field density functional theory of a three-phase contact line.

We investigate generalized potentials for a mean-field density functional theory of a three-phase contact line. Compared to the symmetrical potential introduced in our previous article [Phys. Rev.

Mean-field density functional theory of a three-phase contact line.

A three-phase contact line in a three-phase fluid system is modeled by a mean-field density functional theory. We use a variational approach to find the Euler-Lagrange equations. Analytic solutions are obtained in the two-phase regions at large distances from the contact line.

Growth of an ice disk: dependence of critical thickness for disk instability on supercooling of water.

The appearance of an asymmetrical pattern that occurs when a disk crystal of ice grows from supercooled water was studied by using an analysis of growth rates for radius and thickness. The growth of the radius is controlled by transport of latent heat and is calculated by solving the diffusion equation for the temperature field surrounding the disk. The growth of the thickness is governed by the generation and lateral motion of steps and is expressed as a power function of the supercooling at the center of a basal face.

Diffuse-reflection boundary conditions for a thermal lattice Boltzmann model in two dimensions: evidence of temperature jump and slip velocity in microchannels.

We discuss the implementation of diffuse reflection boundary conditions in a thermal lattice Boltzmann model for which the upwind finite difference scheme is used to solve the set of evolution equations recovered after discretization of the velocity space. Simulation of heat transport between two parallel walls at rest shows evidence of temperature jumps at the walls that increase with Knudsen number. When the walls move in opposite directions with speeds +/- u(W), fluid velocity slip is observed at the walls, together with temperature jumps.

Mass and thermal diffusivity algorithms: reduced algorithms for mass and thermal diffusivity determinations.

Mass and thermal diffusivity measurements conducted on Earth are prone to contamination by uncontrollable convective contributions to the overall transport. Previous studies of mass and thermal diffusivities conducted on spacecraft have demonstration the gain in precision, and lower absolute values, resulting from the reduced convective transport possible in a low-gravity environment. We have developed and extensively tested real-time techniques for diffusivity measurements, where several measurements may be obtained on a single sample.

Thermodynamic basis for a variational model for crystal growth.

Variational models provide an alternative approach to standard sharp interface models for calculating the motion of phase boundaries during solidification. We present a correspondence between objective functions used in variational simulations and specific thermodynamic functions. We demonstrate that variational models with the proposed identification of variables are consistent with nonequilibrium thermodynamics.