computational fluid dynamics (cfd) simulations of gas-solid flow through a positive low-pressure pneumatic conveyor were performed using eulerian-eulerian framework. pressure drop in pneumatic conveying pipelines, creation and destruction of plugs along the horizontal and vertical pipes, effect of 90° elbows and u-bends on cross-section concentrations, and rope formation and dispersion were num...

explosion has always been regarded as one of the most complicated engineering problems. as a result, many engineers have preferred rather simplified empirical approaches in comparison to extremely complex deterministic analyses. in this paper, however, a numerical simulation based on the combined finite/discrete element methodology is presented for analyzing the dynamic behavior of fracturing r...

Two-interconnected fluidized bed systems are widely used in various processes such as Fisher-Tropsch, hot gas desulfurization, CO2 capture-regeneration with dry sorbent, chemical-looping combustion, sorption enhanced steam methane reforming, chemical-looping hydrogen generation system, and so on. However, most of two-interconnected fluidized beds systems require riser and/or pneumatic transport...

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...

We study surface nanobubbles using molecular dynamics simulation of ternary (gas, liquid, solid) systems of Lennard-Jones fluids. They form for a sufficiently low gas solubility in the liquid, i.e., for a large relative gas concentration. For a strong enough gas-solid attraction, the surface nanobubble is sitting on a gas layer, which forms in between the liquid and the solid. This gas layer is...

We present searches for gas–phase CO2 features in the ISO–SWS infrared spectra of four deeply embedded massive young stars, which all show strong solid CO2 absorption. The abundance of gas–phase CO2 is at most 2: 10 7 with respect to H2, and is less than 5% of that in the solid phase. This is in strong contrast to CO, which is a factor of 10–100 more abundant in the gas than in solid form in th...

We present searches for gas–phase CO2 features in the ISO–SWS infrared spectra of four deeply embedded massive young stars, which all show strong solid CO2 absorption. The abundance of gas–phase CO2 is at most 2: 10 7 with respect to H2, and is less than 5% of that in the solid phase. This is in strong contrast to CO, which is a factor of 10–100 more abundant in the gas than in solid form in th...