Scaling is an integral component of ecology and earth science. To date, the ability to determine the importance of air – water gas exchange across large spatial scales is hampered partly by our ability to scale the gas transfer velocity and stream hydraulics. Here we report on a metadata analysis of 563 direct gas tracer release experiments that examines scaling laws for the gas transfer veloci...

Extended abstract Understanding the complexity of the fluid dynamics in bubble column and airlift reactors is important due to their application in the chemical and bioprocess industries. So the objective of this research was to develop a fundamental understanding of the hydrodynamics and interactions with the chemistries involved in the bubble column reactor to maximize overall efficiency for ...

The local solid flow structure of gas-solid bubbling fluidized bed was investigated to identify and characterize the particle clusters. Extensive mathematical calculations were carried out using the energy-minimization multi-scale (EMMS) approach for evaluating cluster properties including the velocity, the size and the void fraction of clusters in the dense phase of the bed. The results showed...

This study is concerned with the prediction of particles’ velocity in a dilute turbulent gas-solidboundary layer flow using a fully Eulerian two-fluid model. The closures required for equationsdescribing the particulate phase are derived from the kinetic theory of granular flows. Gas phaseturbulence is modeled by one-equation model and solid phase turbulence by MLH theory. Resultsof one-way and...

Liquid unloading is a very common and important issue in horizontal gas wells, the presence of curve sections increases complexity phenomenon its study. loading well will sharply reduce production, therefore, liquid-unloading onset different curved pipes essential to production. In this work, experiments were conducted with curvatures. Then, critical velocity V sgCR can be determined according ...

A series of experiments were conducted to investigate the flow pattern transitions and water holdup during oil–water–gas three-phase considering both a horizontal section vertical transportation pipe simultaneously. The flowing media white mineral oil, distilled water, air. Dimensionless numbers controlling multiphase deduced understand scaling law process. was simplified as two-phase gas liqui...

Odour control from pig production facilities is a significant concern due to increased public awareness and the development of more stringent legislation to control production. Although many technologies exist, biofiltration is still the most attractive due to its low maintenance and operating costs. One of the key odour components, n-butyric acid, was selected for a laboratory scale biofilter ...

a total of 1118 soldiers who were wounded in war and hospitalized in tehran, were examined for p .versicolor-a superficial mycotic infection. of these, 213 were war-wounded, 54 chemical (mustard) gas-wounded, 42 both war and chemical gas-wounded, 105 had infectious and noninfectious diseases, and 704 were apparently healthy soldiers serving in war fronts who were examined for p. versicolor and ...

Objective Argon plasma coagulation (APC) and helium plasma coagulation (HPC) are electrosurgical techniques that provide noncontact monopolar electrothermal haemostasis. Although these techniques have been widely used clinically during the last three decades, their in vivo effects on liver tissue remain unclear. Methods We investigated the effects of different power levels (10-100 W) of APC and...

In this paper computational analysis of circulating fluidized bed combustion using the fluent software is analysed. This work is concerned about gas–solid two-phase mixtures flowing upwards through the fast beds. The procedures studied are applicable to all types of fluidized-bed boilers. The type of information resulting from various ways of analyzing the pressure and temperature in fluidized ...