Axial Inlet Geometry Effects on the Flow Structures in a Cyclone Burner Related to the Combustion Performance of Biomass Particles
DOI:
https://doi.org/10.5614/j.eng.technol.sci.2018.50.5.7Keywords:
axial inlet diameter, biomass particles, decomposition process, flow structure, k- turbulent model, pressure drop, turbulent intensity, vortexAbstract
Solid fuel combustion is always preceded by chemical decomposition. This process is largely determined by the flow structure and affected by the geometry and operating conditions of the combustion chamber. This study aimed to investigate the effect of relative axial inlet diameter (Dai//Dbc) on the flow structure in the proposed cyclone burner. The flow structure was determined with the standard k-e turbulent model using the Ansys-Fluent software. From the simulation results it was concluded that with all the axial inlet diameters used an integrated vortex formed in the center of the burner cylinder. The integrated vortex consisted of two vortices, namely a primary vortex and a secondary vortex. The primary vortex penetrated from the furnace box to the burner cylinder, while the secondary vortex was formed in the burner cylinder itself. There were two integration patterns from the primary vortex and the secondary vortex, namely a summation pattern and a multilayer pattern. The presence of a vortex in the center of the burner cylinder is allegedly responsible for an increase in the degree of mixing and pressure drop in that zone. The flow structure induced from the proposed burner had high symmetricity and was largely determined by the burner's axial inlet diameter.Downloads
References
Li, J., Paul, M.C., Younger, P.L., Watson, I., Hossain, M. & Welch, S., Combustion Modelling of Pulverized Biomass Particles at High Temperatures, Energy Procedia, 66, pp. 273-276, 2015.
Baxter, L., Ip, L., Lu, H. & Tree, D., Distinguishing Biomass Combustion Characteristics and Their Implications for Sustainable Energy, Proc. of 5th Asia Pacific Conference on Combustion, University of Adelaide, Australia, pp. 469-473, 2005.
Momeni, M., Yin, C., Kr, S.K., Hansen, T.B., Jensen, P.A. & Glarborg, P., Experimental Study on Effects of Particle Shape and Operating Conditions on Combustion Characteristics of Single Biomass Particles, Energy & Fuels, 27, pp. 507-514, 2013.
Vassilev, S.V., Vassileva, C.G. & Vassilev, V.S., Advantages and Disadvantages of Composition and Properties of Biomass in Comparison with Coal: An Overview, Fuel, 158, pp. 330-350, 2015.
Baxter, X.C., Darvell, L.I., Jones, J.M., Barraclough, T., Yates, N.E. & Shield, I., Miscanthus Combustion Properties and Variations with Miscanthus Agronomy, Fuel, 117, pp. 851-869, 2014.
Kops, S.M.B. & Malte, P.C., Simulation and Modeling of Wood Dust Combustion in Cyclone Burners, Final Technical Report (1-49), University of Washington, Washington DC, United States, 2004.
Nemoda, S., Bakic, V., Oka, S., Zivkovic, G. & Crnomarkavic, N., Experimental and Numerical Investigation of Gaseous Fuel Combustion in Swirl Chamber, International Journal of Heat and Mass Transfer, 48, pp. 4623-4632, 2005.
Ziqiang, L.V., Guangqiang, L. & Yingjie, L., Optimization Study on Bias Angle of a Swirl Burner with Tangential Inlet Air, International Journal of Smart Home, 10, pp. 171-180, 2016.
Arnao, J.H.S., Ferreira, D.J.O., Santos, C.G., Alvarez, J.E., Rangel, L.P. & Park, S.W., The Influence of Swirl Burner Geometry on the Sugar-Cane Bagasse Injection and Burning, International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering, 9, pp. 798-801, 2015.
Pasymi, Budhi, Y.W. & Bindar, Y., Effect of Initial Tangential Intensity on the Fluid Dynamic Characteristics in Tangential Burner, MATEC Web of Conferences, 101, pp. 1-6, 2017.
Nag, P.K., Power Plant Engineering, Second Edition, McGraw Hill Company, Singapore, 2002.
Xia, B. & Sun, D.W., Applications of Computational Fluid Dynamics (CFD) in the Food Industry, Journal of Computers and Electronics in Agriculture, 34, pp. 5-24, 2002.
Pragati, K. & Sharma, H.K., Concept of Computational Fluid Dynamics (CFD) and its Applications in Food Processing Equipment Design, Journal of Food Processing and Technology, 3, pp. 1-7, 2013.
Bindar, Y., Geometry Effect Investigation on a Conical Chamber with Porous Media Boundary Condition Using Computational Fluid Dynamic (CFD) Technique, J. Eng. Technol. Sci. (formerly as ITB J. Eng. Sci.), 41, pp. 97-110, 2009.
Vazquez, J.A.R., A Computational Fluid Dynamics Investigation of Turbulent Swirling Burners, PhD Thesis, University of Zaragoza, Spain, 2012.
Bindar, Y., Computationl Engineering on Multi-Dimensional Turbulent Flows (in Indonesian Language), First Edition, ITB Press, Bandung, 2017.
Al-Abdeli Y.M. & Masri, A.R., Review of Laboratory Swirl Burners and Experiments for Model Validation, Journal of Experimental Thermal and Fluid Science, 69, pp. 178-196, 2015.
Ahsan, M. & Hussain, A., Computational Fluid Dynamics (CFD) Simulation and Comparison for Different Numbers of Baffles to Reduce Concentration Polarization Effects in Membrane Tubes, J. Eng. Technol. Sci., 49, pp. 114-131, 2017.