Sieve trays are widely used in the gas- liquid contactors such as distillation and absorption towers. In this article, a three-dimensional, two phase CFD model using Euler-Euler framework was developed to simulate a distillation tower with two sieve trays. Hydrodynamic simulation of air and water system in different rates of gas phase was carried out and velocity distribution parameters, clear ...

We present an alternative explanation for the nature of turbulence in molecular clouds. Often associated with classical models of turbulence, we instead interpret the observed gas dynamics as random motions, induced when clumpy gas is subject to a shock. From simulations of shocks, we show that a supersonic velocity dispersion occurs in the shocked gas provided the initial distribution of gas i...

In this work, new experimental data for slugging frequency in inclined gas-liquid flow are reported, and a new correlation is proposed. Scale experiments were carried out using a mixture of air and water in a 6 m long pipe. Two different pipe diameters were used, namely, 38 and 67 mm. The data were taken with capacitance type sensors at a data acquisition frequency of 200 Hz over an interval of...

Hydrocracking has great importance in present day refining due to strict environmental and norms of quality of fuel. In recent years the demand for middle distillate and gasoline has increased tremendously while that of heavy gas has decreased. In the present work we have modeled and then applied five lump scheme to hydrocracker reactor. The first order kinetics was assumed for the conversion i...

The rising incidence of diabetes and its negative impact on quality of life highlights the urgent need to develop biomarkers of early nerve damage. Measurement of total vitamin B12 has some limitations. We want to determine the levels of urinary methylmalonic acid and its relationships with serum vitamin B12 and polyneuropathy. The 176 Chinese patients with Type 2 diabetes mellitus were divided...

Sampling of triethylamine in the cold-box unit in an auto-manufacturing company in Iran has indicated the average concentration of 430 mg/m3 in the emission duct. In this study a biotrickling filter was used for treatment of triethylamine in air stream. Triethylamine removal efficiency (K/L) pattern was evaluated by changing volumetric loading (L), superficial gas velocity (Uo), empty bed gas r...

Regenerative Thermal Oxidizers (RTO) are extensively used when waste gases containing low solvent mixture concentration, generally between 0.25 and 5.00 gr/Nmc, have to be treated in order to reach established limits. A lot of manufacturers around the world are involved in this job, but still many factors are unclear, among these are: • temperature of ceramic packing bed • temperature differenc...

Blast furnace gas is the byproduct of smelting steel production process, and is the important secondary energy source. It is can be used as fuel for engines to generate electricity for most middle and small steel enterprises. In order to understand the combustion mechanism and provide the basis for the design of blast furnace gas engine,premixed laminar combustion experiments of the blast furna...

We have investigated dynamic behavior of a dust flow with velocity shear in RF plasmas. In this study, neutral drag force by the neutral gas ejected from small nozzles is used for driving directional dust flows with velocity shear. The strength of the velocity shear can be controlled over a wide range by adjusting the direction of the nozzles and the flow rate of the neutral gas. The dust parti...