Incompressible, inviscid, irrotational, unsteady flows with circulation Gamma around a distorted toroidal bubble are considered. A general variational principle that determines the evolution of the bubble shape is formulated. For a two-dimensional (2D) cavity with a constant area A, exact pseudodifferential equations of motion are derived, based on variables that determine a conformal mapping o...

In this work, we develop a self-consistent physical model of bubbles in a gas-solid 1 two-phase flow. Based on PR state equation, and a detailed specific heat ratio equation of bubbles, 2 we self-consistently evaluate kinetic equations of the bubbles on the basis of Ergun equation, 3 thermodynamic equation and kinetic equations. It is found that the specific heat ratio of bubbles in 4 such syst...

Quantifying the mechanical forces produced by fluid flows within the ocean is critical to understanding the ocean's environmental phenomena. Such forces may have been instrumental in the origin of life by driving a primitive form of self-replication through fragmentation. Among the intense sources of hydrodynamic shear encountered in the ocean are breaking waves and the bursting bubbles produce...

In this work, we develop a self-consistent physical model of bubbles in a gas solid two-phase 1 flow. Using the Peng-Robonson state equation and a detailed specific heat ratio equation of bubbles, 2 we obtain the kinetic equations of the bubbles on the basis of the Ergun equation, thermodynamic 3 equations, and kinetic equations. It is found that the specific heat ratio of bubbles in such syste...

The purpose of this study was to evaluate the performance laboratory-scale biotrickling filters (BTFs) packed with composite filler and pine bark under different operating conditions in purifying mixed gas containing H2S NH3. prepared modified activated carbon loaded functional microbes, using microbial immobilization technology combined a nutrient sustained-release filler. results showed that ...

There is a variation in the depth of subsurface horizon Planosols semi-arid region, which may influence agricultural potential and affect food production. The general aim this study was to identify potentialities limitations two as function depth. adjacent profiles P1 P2 were studied Pentecoste (Ceará, Brazil). Morphological, physical, chemical analyses done aiming at soil characterization. Soi...

We propose a new technique for efficiently rendering bidirectional texture functions (BTFs). A 6D BTF describes the appearance of a material as a texture that depends on the lighting and viewing directions. As such, a BTF accommodates self-shadowing, interreflection, and masking effects of a complex material without needing an explicit representation of the small scale geometry. Our method repr...

Steady-state and transient experiments of water–gas, oil–water and oil–water–gas multiphase flows were conducted on a transparent 11 m long, 15 cm diameter, inclinable pipe using kerosene, tap water and nitrogen. The pipe inclination was varied from 0 (vertical) to 92 and the flow rates of each phase were varied over wide ranges. Fast-acting valves enabled the trapping of the fluid flowing in t...

We have studied bubble motion within a column of foam allowed to undergo free drainage. We have measured bubble motion upward with time and as a function of their initial positions. Depending on the gas used, which sets the coarsening and drainage rates, different bubble upward motion types have been identified (constant speed, acceleration or deceleration) and explained in relation with liquid...

The Rayleigh-Plesset equation is used extensively to model spherical bubble dynamics, yet it has been shown that it cannot correctly capture damping effects due to mass and thermal diffusion. Full single bubble models have been successfully used to study these diffusion effects, but these are too computationally expensive to implement into the continuum model for bubbly cavitating flows since t...