Computational fluid dynamic simulation

FIG. 6-56 Computational fluid dynamic simulation of flow over a square cylinder, showing one vortex shedding period. (From Choudliuty, et al., Trans. ASME Fluids Div, TN-076[1994].)... 

Logtenberg, S. A., Nijemeisland, M., and Dixon, A. G., Computational fluid dynamics simulations of fluid flow and heat transfer at the wall-particle contact points in a fixed-bed reactor, Chem. Eng. Sci. 54, 2433-2439 (1999). 

In this chapter, a number of transport phenomena with entirely different natures are compared for liquids filling porous systems. Here transport can refer to flow, diffusion, electric current or heat transport. Corresponding NMR measuring techniques will be described. Applications to porous model objects will be juxtaposed to computational fluid dynamics simulations. 

Computational fluid dynamic simulator ht-MAH CFD simulation OT indoor airflow and pollutant dispersion Trained %... 

Software tools are applied in every step of process development. Tools for individual reactor simulations such as computational fluid dynamic simulations are not the topic in this chapter. These tools supply only numerical data for specific defined reactor geometry and defined specific process conditions. A change of parameter would demand a complete recalculation, which is often a very time-consuming process and not applicable to a parameter screening. Methods for reactor optimization by CFD are described in detail in the first volume of this series. Tools for process simulation allow the early selection of feasible process routes from a large... 

Computational Fluid Dynamics Simulation and Redesign of a Screw Conveyor Reactor... 

Dembele, S., Zhang, J., and Wen, J.X. Assessments of spectral narrow band and weighted-sum-of-gray-gases models for computational fluid dynamics simulations of pool fires. Numerical Heat Transfer Part B, 2005.48(3), 257-276. 

A. K. Das. Computational fluid dynamics simulation of gas-solid risers reactive flow modelling. Phd thesis, Universiteit Gent, 2002. 

Hjertager, B. H., and Morud, K., Computational fluid dynamics simulation of bioreactors. In Bioreactor Performance (U. Mortensen and H. J. Noorman, eds.). Ideon, Lund, 1993, p. 47. 

Computational fluid dynamics simulations were used by Li et al. [68] to determine mass transfer coefficients and power consumption in channels filled with non woven net spacers. The geometric parameters of a non woven spacer were found to have a great influence on the performance of a spacer in terms of mass transfer enhancement and power consumption. The results from the CFD simulations indicated that an optimal spacer geometry exists. 

Computational Fluid Dynamics Simulation of Polymer Flow for Die Design... 

Subramaniam RP, Richardson RB, Morgan KT, et al. 1998. Computational fluid dynamics simulations of inspiratory airflow in the human nose and nasopharynx. Inhal Toxicol 10 473-502. 

Mixing properties and flow fields in stirred tanks are usually studied on a laboratory scale. Practical scale-up of a stirred tank cannot be performed requiring that every individual mixing and fluid mechanical parameters in the small scale tank should be maintained in the larger one. Therefore, scale-up procedures for different types of processes have been determined through experience, testing and computational fluid dynamics simulations. 

The effect of micromixing in the iodination reaction is smaller than that observed for the Friedel-Crafts alkylation using N-acyliminium ions. The smaller effect seems to be ascribed to the smaller rate of iodination, because computational fluid dynamics simulation indicated that the effect of the micromixing on the product selectivity of a competitive consecutive reaction increases with an increase in the reaction rate. Therefore, the electrochemically generated I seems to be less reactive than the N-acyliminium ions. 

Bottom row results from FEMLAB computational fluid dynamic simulation of process. 

COMPUTATIONAL FLUID DYNAMICS SIMULATIONS OF SUPERSONIC JET-NOISE REDUCTION CONCEPTS... 

Figure 4.1-4. Computational fluid dynamics simulation of vapor fraction formation from a tube contraction as a function of tube length (diameter = 500pm, pressure drop = 3.45 MPa). Red areas indicate 100% vapor regions within the pipe. (This figure is available in full color at ftp //ftp.wiley.com/public/sci tech med/pharmaceutical biotech/.)...

Trivex Pin. Two-dimensional (2-D) computational fluid dynamics simulations were used to examine material flow around a series of pin... 

Computational fluid dynamic simulations have been nsed to model the drop/partiele trajectories in spray-drying (Gianfrancesco et al., 2010), but optimization is still complex. 

L. Huang, K. Kumar, A.S. Mujumdar, A comparative study of a spray dryer with rotary disc atomizer and pressure nozzle using computational fluid dynamic simulations, Chemical Engineering and Processing, 45 (2006) 461-470. 

Morud K, Hjertager BH (1993) Computational fluid dynamics simulations of bioreactors. In Mortensen U, Noorman H (eds) Bioreactor performance. IDEON, Lund, Sweden, p 47... 

Shi, Y., Isaac, K., Miles, J.B. (1997). Computational fluid dynamics simulation of turbulent waverider flow field with sideslip. Journal of Spacecraft and Rockets 34(1) 76-82. 

Akbar and Ghiaasiaan [10] conducted computational fluid dynamics simulations to model a unit cell (one bubble and two half-liquid slugs) in a capillary of 1 mm diameter. Their numerical results, as well as experimental data from previous investigators, were predicted well by the following equation ... 

The model provided excellent agreement with computational fluid dynamic simulations for capillaries with 1.5, 2, and 3 mm diameters and idealized bubble geometry as shown in Figure 7.12 [47]. The major contribution to mass transfer is in the film k fiim fUm) concentration of the solute is low in the... 

Panneerselvam R, Savithri S, Surender GD. (2009) Computational fluid dynamics simulation of solid suspension in a gas-liquid-solid mechanically agitated contactor. Ind. Eng. Chem. Res., 48 1608-1620. 

Mass-transport (i.e., diffusion or electromigration) effects are particularly acute in the cases of cracking, pitting, and crevice corrosion, whereby occlusion effects can create highly concentrated solutions that move an otherwise stable system into regions of thermodynamic instability at the local level [13,14,41 3, 79-82]. When porous films or particular solution flow conditions exist, mass-transport effects should also be taken into account [83, 84]. Molecular dynamics and Monte Carlo simulations of interfaces over the past few decades have provided some insight into the concentration gradients that occur close to the electrochemical interface [85-91], and these, coupled with computational fluid dynamics simulations, can indicate the extent to which mass-transport effects can dominate an overall corrosion scenario [92]. 

Bubble (and slug) lengths have been obtained experimentally or through computational fluid dynamic simulations [28-30]. These revealed that sizes are mainly affected by gas and liquid superficial velocities and contactor size and slightly by... 

Accurate CFD (computational fluid dynamic) simulation of the flow in stirred tanks requires correct specification of both the geometry and the physical conditions of the flow. While specification of the geometry, the gridding, and the solution algorithm is relatively straightforward, some other issues remain difficult. The most challenging problem is definition of a physically accurate, computationally tractable impeller or impeller model which incorporates the effect of the tank geometry. This... 

Computational Fluid Dynamic Simulation Using Supercomputer Calculation Capacity... 

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