**8. References**


http://www.osti.gov/energycitations/servlets/purl/881590-Kfq80v/.


54 Advanced Fluid Dynamics

Computational fluids dynamics is a very powerful tool understanding the behavior of multi

Large eddy simulation (LES) turbulence method provides a very detailed description of two phase flow, which makes it suitable for simulation models that are validated with experimental data. By applying the LES method, it is possible to characterize different regions of a fluidized bed (core-annulus). LES can be considered as a valuable method for development and validation of closure models that include additional phenomena like heat

It is important to constantly monitor the simulation, using parameters such as the Courant number, creating a function that calculates the maximum and average number of the control

Finally, it is important to comment that success in the validation of experimental data depends on the appropriate choice of the experimental technique used to measure variables.

The author G. Gonzalez is grateful to PETROBRAS and the National Council for Scientific

Agrawal, Kapil, Peter N Loezos, Madhava Syamlal, and Sankaran Sundaresan. 2001. "The

Ahmed, A. M., and S. Elghobashi. 2000. "On the mechanisms of modifying the structure of

Al-Dahhan, Muthanna, Milorad P. Dudukovic, Satish Bhusarapu, Timothy J. O'hern, Steven

Al-Hasan, M., and Z. Al-Qodah. 2007. Characteristics of gas-solid flow in vertical tube. In

Ancheyta, Jorge. 2010. *Modeling and simulation of catalytic reactors for petroleum refining*.

Bader, R., Findlay, J. and Knowlton, TM. 1988. Gas/ Solid Flow Patterns in a 30.5-cm-

Bhusarapu, S., M.H. Al-Dahhan, and M.P. Duduković. 2006. "Solids flow mapping in a gassolid riser: Mean holdup and velocity fields." *Powder Technology* 163 (1-2): 98-123. van Buijtenen, Maureen S., Willem-Jan van Dijk, Niels G. Deen, J.A.M. Kuipers, T.

Computer Automated Radioactive Particle Tracking (CARPT). http://www.osti.gov/energycitations/servlets/purl/881590-Kfq80v/.

role of meso-scale structures in rapid gas solid flows." *Journal of Fluid Mechanics* 445

turbulent homogeneous shear flows by dispersed particles." *Physics of Fluids* 12

Trujillo, and Michael R. Prairie. 2005. Flow Mapping in a Gas-Solid Riser via

*9th International Symposium on Fluid Control Measurement and Visualization 2007,* 

Diameter Circulating Fluidized Bed. In *Circulating fluidized bed technology II: proceedings of the Second International Conference on Circulating Fluidized Beds, Compiègne, France, 14-18 March 1988*, by Prabir Basu and Jean François Large.

Leadbeater, and D.J. Parker. 2011. "Numerical and experimental study on multiple-

volume courant. The average value is recommended that is near or less than unity.

and Technological Development (CNPq) for the financial support to this research.

**6. Conclusions** 

phase in engineering applications.

**7. Acknowledgements** 

(01) (October): 151-185.

(11): 2906. doi:10.1063/1.1308509.

*FLUCOME 2007*, 1:264-271.

Oxford: Wiley-Blackwell.

Pergamon Press.

**8. References** 

exchange, mass transfer and chemical reactions.

spout fluidized beds." *Chemical Engineering Science* 66 (11) (June 1): 2368-2376. doi:16/j.ces.2011.02.055.


Fluid Dynamics of Gas – Solid Fluidized Beds 57

Link, J.M., W. Godlieb, P. Tripp, N.G. Deen, S. Heinrich, J.A.M. Kuipers, M. Schönherr, and

Lu, Y., D.H. Glass, and W.J. Easson. 2009. "An investigation of particle behavior in gas-solid horizontal pipe flow by an extended LDA technique." *Fuel* 88 (12): 2520-2531. Mathiesen, V. 2000. "An experimental and computational study of multiphase flow behavior

Mathiesen, Vidar, Tron Solberg, Hamid Arastoopour, and Bjørn H Hjertager. 1999.

Miller, Aubrey, and Dimitri Gidaspow. 1992. "Dense, vertical gas‐solid flow in a pipe." *AIChE Journal* 38 (11) (November 1): 1801-1815. doi:10.1002/aic.690381111. Newton, D., M. Fiorentino, and G.B. Smith. 2001. "The application of X-ray imaging to the developments of fluidized bed processes." *Powder Technology* 120 (1-2): 70-75.

Petritsch, Georg, Nicolas Reinecke, and Dieter Mewes. 2000. Visualization Techniques in

Samuelsberg, A., and B. H. Hjertager. 1996. "An experimental and numerical study of flow

Sathe, M.J., I.H. Thaker, T.E. Strand, and J.B. Joshi. 2010. "Advanced PIV/LIF and

Tan, H.-T., G.-G. Dong, Y.-D. Wei, and M.-X. Shi. 2007. "Application of γ-ray attenuation

Tapp, H.S., A.J. Peyton, E.K. Kemsley, and R.H. Wilson. 2003. "Chemical engineering

Tavoulareas, E S. 1991. "Fluidized-Bed Combustion Technology." *Annual Review of Energy and* 

Thatte, A. R., R. S. Ghadge, A. W. Patwardhan, J. B. Joshi, and G. Singh. 2004. "Local Gas

Vaishali, S., S. Roy, S. Bhusarapu, M.H. Al-Dahhan, and M.P. Dudukovic. 2007. "Numerical

Process Engineering. In *Ullmann's Encyclopedia of Industrial Chemistry*. Wiley-VCH

patterns in a circulating fluidized bed reactor." *International Journal of Multiphase* 

shadowgraphy system to visualize flow structure in two-phase bubbly flows."

technology in measurement of solid concentration of gas-solid two-phase flow in a FCC riser." *Guocheng Gongcheng Xuebao/The Chinese Journal of Process Engineering* 7

applications of electrical process tomography." *Sensors and Actuators, B: Chemical* 92

*the Environment* 16 (1) (November): 25-57. doi:10.1146/annurev.eg. 16.110191.000325.

Holdup Measurement in Sparged and Aerated Tanks by γ-Ray Attenuation Technique." *Industrial & Engineering Chemistry Research* 43 (17): 5389-5399.

simulation of gas-solid dynamics in a circulating fluidized-bed riser with geldart group B particles." *Industrial and Engineering Chemistry Research* 46 (25): 8620-8628.

Niccum Phillip K, and Bunn Jr Dorrance P. 1983. Catalytic Cracking System. March 23. Patankar, Suhas. 1980. *Numerical heat transfer and fluid flow*. Washington; New York:

*Technology* 189 (2): 202-217. doi:16/j.powtec.2008.04.017.

(March): 387-419. doi:10.1016/S0301-9322(99)00027-0.

*(Fourth Edition)*, 191-216. Boston: Butterworth-Heinemann.

*Flow* 22 (3) (June): 575-591. doi:16/0301-9322(95)00080-1.

*Chemical Engineering Science* 65 (8): 2431-2442.

Hemisphere Pub. Corp; McGraw-Hill.

Verlag GmbH & Co. KGaA.

(5): 895-899.

(1-2): 17-24.

doi:10.1021/ie049816p.

M. Peglow. 2009. "Comparison of fibre optical measurements and discrete element simulations for the study of granulation in a spout fluidized bed." *Powder* 

in a circulating fluidized bed." *International Journal of Multiphase Flow* 26 (3)

"Experimental and computational study of multiphase gas/particle flow in a CFB riser." *AIChE Journal* 45 (12) (December 1): 2503-2518. doi:10.1002/aic.690451206. Meggitt, B.T. 2010. Fiber Optics in Sensor Instrumentation. In *Instrumentation Reference Book* 


56 Advanced Fluid Dynamics

He, Y., N. G. Deen, M. van Sint Annaland, and J. A. M. Kuipers. 2009. "Gas−Solid Turbulent

Heindel, Theodore J., Joseph N. Gray, and Terrence C. Jensen. 2008. "An X-ray system for

Hernández-Jiménez, F., S. Sánchez-Delgado, A. Gómez-García, and A. Acosta-Iborra.

http://www.sciencedirect.com/science/article/pii/S0009250911002685. Ibsen, C.H., T. Solberg, and B.H. Hjertager. 2001. "Evaluation of a three-dimensional

Ibsen, Claus H., Tron Solberg, Bjørn H. Hjertager, and Filip Johnsson. 2002. "Laser Doppler

Jespersen, Dennis C, and Timothy J Barth. 1989. "The design and application of upwind

Kashyap, Mayank, and Dimitri Gidaspow. 2011. "Measurements of Dispersion Coefficients

Khanna, Pankaj, Todd Pugsley, Helen Tanfara, and Hubert Dumont. 2008. "Radioactive

Kim, J. M, and J. D Seader. 1983. "Pressure drop for cocurrent downflow of gas‐solids suspensions." *AIChE Journal* 29 (3) (May 1): 353-360. doi:10.1002/aic.690290302. Kuan, B., W. Yang, and M.P. Schwarz. 2007. "Dilute gas-solid two-phase flows in a curved

Kumar, Sailesh B., Davood Moslemian, and Milorad P. Dudukovic. 1995. "A [gamma]-ray

Larachi, Faical, M H Al-Dahhan, M P Duduković, and Shantanu Roy. "Optimal design of

Laverman, Jan Albert, Ivo Roghair, Martin van Sint Annaland, and Hans Kuipers. 2008.

*Chemical Engineering* 86 (3) (June 1): 523-535. doi:10.1002/cjce.20054.

schemes on unstructured meshes." *AIAA paper* 89 (89-0366): 1–12.

(12) (June 15): 7549-7565. doi:10.1021/ie1012079.

*use in agriculture industry and medicine* 56 (3): 485-503.

8091-8097. doi:10.1021/ie8015285.

doi:16/j.flowmeasinst.2007.09.003.

*Chemistry Research* 40 (23): 5081-5086.

1): 563-570. doi:10.1002/cjce.20073.

*Science* 62 (7): 2068-2088.

Butterworth-Heinemann.

6.

Flow in a Circulating Fluidized Bed Riser: Experimental and Numerical Study of Monodisperse Particle Systems." *Industrial & Engineering Chemistry Research* 48 (17):

visualizing fluid flows." *Flow Measurement and Instrumentation* 19 (2) (April): 67-78.

"Comparison between two-fluid model simulations and particle image analysis & velocimetry (PIV) results for a two-dimensional gas-solid fluidized bed." *Chemical Engineering Science* In Press, Corrected Proof. doi:16/j.ces.2011.04.026.

numerical model of a scaled circulating fluidized bed." *Industrial and Engineering* 

anemometry measurements in a circulating fluidized bed of metal particles." *Experimental Thermal and Fluid Science* 26 (6-7): 851-859. doi:16/S0894-1777(02)00196-

for FCC Particles in a Free Board." *Industrial & Engineering Chemistry Research* 50

particle tracking in a lab‐scale conical fluidized bed dryer containing pharmaceutical granule." *The Canadian Journal of Chemical Engineering* 86 (3) (June

90° duct bend: CFD simulation with experimental validation." *Chemical Engineering* 

tomographic scanner for imaging voidage distribution in two-phase flow systems." *Flow Measurement and Instrumentation* 6 (1): 61-73. doi:16/0955-5986(95)93459-8. Kunii, D, and O Levenspiel. 1991. *Fluidization engineering.* 2nd ed. Boston Mass.:

radioactive particle tracking experiments for flow mapping in opaque multiphase reactors." *Applied radiation and isotopes including data instrumentation and methods for* 

"Investigation into the hydrodynamics of gas–solid fluidized beds using particle image velocimetry coupled with digital image analysis." *The Canadian Journal of* 


**4**

*USA* 

**Fuel Jet in Cross Flow –**

**Experimental Study of Spray Characteristics** 

*School of Aerospace Engineering, Georgia Institute of Technology, Atlanta Georgia* 

Injection of the liquid fuel across the incoming air flow is widely used in gas turbine engine combustors. Thus it is important to understand the mechanisms that control the breakup of the liquid jet and the resulting penetration and distribution of fuel droplets. This understanding is needed for validation of Computational Fluid dynamics (CFD) codes that will be subsequently incorporated into engine design tools. Additionally, knowledge of these mechanisms is needed for interpretation of observed engine performance characteristics at different velocity/altitude combinations of the flight envelope and development of qualitative approaches for solving problems such as combustion instabilities (Bonnel et al., 1971). This chapter provides an introduction and literature review into the subject of cross-flow fuel injection and describes the fundamental physics involved. Additionally highlighted are experimental technique and recent experimental data describing the variables involved in fuel spray penetration and fuel column disintegration. In recent years, there has been a great drive to reduce harmful emissions of oxides of Nitrogen oxides (NOx) from aircraft engines. One of the several approaches to achieve low emissions is to avoid hot spots in combustors by creating a lean homogeneous fuel-air mixture just upstream of the combustor inlet. This concept is termed as Lean Premixed Prevaporized (LPP) combustion. Creating such a mixture requires fine atomization and careful placement of fuel to achieve a high degree of mixing. Liquid jet in cross flow, being able to achieve both of these requirements, has gained interest as a likely candidate for spray creation in LPP ducts (Becker & Hassa, 2002). Since the quality of spray formation directly influences the combustion efficiency of engines, it is important to understand the

As seen in Fig. 1, the field of a spray created by a jet in cross flow can be divided into three modes: 1) Intact liquid column, 2) Ligaments, and 3) Droplets. The liquid column develops hydrodynamic instabilities and breaks up into ligaments and droplets (Marmottant & Villermaux, 2004; Madabushi, 2003; Wu et al., 1997). This process is referred to as primary breakup. The location where the liquid column ceases to exist is known as the column breakup point (CBP) or the fracture point. The ligaments breakup further into smaller

The most relevant parameter for drop breakup criterion is the Weber number,

 *fuel* / <sup>2</sup> (in this formula *ρair* and *Uair* - density and velocity of the crossing air respectively, *D* - diameter of the injection orifice and *Ϭfuel* is the surface tension of the fuel).

fundamental physics involved in the formation of spray.

droplets and this process is called secondary breakup.

**1. Introduction** 

*We*

*airUairD* E. Lubarsky, D. Shcherbik, O. Bibik, Y. Gopala and B. T. Zinn

