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Abstract

The present investigation is concerned with the reflection in thermo-microstretch elastic solid in the presence of a transverse magnetic field, at the boundary surface. The generalized theories of thermoelasticity developed by Lord and Shulman [1](L-S) and Green and Lindsay [2](G-L) theories have been used to investigate the problem. The variations of amplitude ratios with angle of incidence have been shown graphically. It is noticed that the amplitude ratios of the reflected waves are affected by magnetic field, stretch and thermal properties of the medium.

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Authors and Affiliations

R. Kumar
Rupender
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Abstract

Biogas is a gaseous biofuel predominantly composed of methane and carbon-dioxide. Stability of biogas flames strongly depend upon the amount of carbon-dioxide present in biogas, which varies with the source of biomass and reactor. In this paper, a comprehensive study on the stability and flame characteristics of coflow biogas diffusion flames is reported. Numerical simulations are carried out using reactive flow module in OpenFOAM, incorporated with variable thermophysical properties, Fick’s and Soret diffusion, and short chemical kinetics mechanism. Effects of carbon-dioxide content in the biogas, temperatures of the fuel or coflowing air streams (preheated reactant) and hydrogen addition to fuel or air streams are analyzed. Entropy generation in these flames is also predicted. Results show that the flame temperature increases with the degree of preheat of reactants and the flames show better stability with the preheated air stream. Preheating the air contributes to increased flame stability and also to a significant decrease in entropy generation. Hydrogen addition, contributing to the same power rating, is seen to be relatively more effective in increasing the flame stability when added to the fuel stream. Results in terms of flow, temperature, species and entropy fields, are used to describe the stability and flame characteristics.
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Bibliography

[1] Z. Recebli, S. Selimli, M. Ozkaymak, and O. Gonc. Biogas production from animal manure. Journal of Engineering Science and Technology, 10(6):722–729, 2015.
[2] S. Rasi, A.Veijanen, and J. Rintala. Trace compounds of biogas from different biogas production plants. Energy, 32(8):1375–1380, 2007. doi: 10.1016/j.energy.2006.10.018.
[3] O. Jonsson, E. Polman, J.K. Jensen, R. Ekund, H. Schyl, and S. Ivarsson. Sustainable gas enters the European gas distribution system. In World Gas Conference, Tokyo, Japan, 2003.
[4] I.U. Khan, M.H.D. Othman, H. Hashim, T. Matsuura, A.F. Ismail, M. Rezaei-DashtArzhandi, and I.W. Azelee. Biogas as a renewable energy fuel – a review of biogas upgrading, utilization and storage. Energy Conversion and Management, 150:277–294, 2017. doi: 10.1016/j.enconman.2017.08.035.
[5] H.O.B. Nonaka and F.M. Pereira. Experimental and numerical study of CO 2 content effects on the laminar burning velocity of biogas. Fuel, 182:382–390, 2016. doi: j.fuel.2016.05.098.
[6] M.S. Abdallah, M.S. Mansour, and N.K. Allam. Mapping the stability of free-jet biogas flames under partially premixed combustion. Energy, 220:119749, 2021. doi: 10.1016/j.energy.2020.119749.
[7] L. Zhang, X. Ren, R. Sun, andY.A. Levendis. A numerical and experimental study on the effects of CO 2 on laminar diffusion methane/air flames. Journal of Energy Resources Technology, 142(8):82307, 2020. doi: 10.1115/1.4046228.
[8] T. Leung and I. Wierzba. The effect of hydrogen addition on biogas non-premixed jet flame stability in a co-flowing air stream. International Journal of Hydrogen Energy, 33(14):3856–3862, 2008. doi: 10.1016/j.ijhydene.2008.04.030.
[9] S. Verma, K. Kumar, L.M. Das, and S.C. Kaushik. Effects of hydrogen enrichment strategy on performance and emission features of biodiesel-biogas dual fuel engine using simulation and experimental analyses. Journal of Energy Resources Technology, 143(9):092301, 2021. doi: 10.1115/1.4049179.
[10] H.S. Zhen, C.W. Leung, and C.S. Cheung. Effects of hydrogen addition on the characteristics of a biogas diffusion flame. International Journal of Hydrogen Energy, 38(16):6874–6881, 2013. doi: 10.1016/j.ijhydene.2013.02.046.
[11] H.S. Zhen, C.W. Leung, and C.S. Cheung. A comparison of the heat transfer behaviors of biogas–H 2 diffusion and premixed flames. International Journal of Hydrogen Energy, 39(2):1137–1144, 2014. doi: 10.1016/j.ijhydene.2013.10.100.
[12] H.S. Zhen, Z.L. Wei, Z.B. Chen, M.W. Xiao, L.R. Fu, and Z.H. Huang. An experimental comparative study of the stabilization mechanism of biogas-hydrogen diffusion flame. International Journal of Hydrogen Energy, 44(3):1988–1997, 2019. doi: 10.1016/j.ijhydene.2018.11.171.
[13] M.R.J. Charest, Ö.L. Gülder, and C.P.T. Groth. Numerical and experimental study of soot formation in laminar diffusion flames burning simulated biogas fuels at elevated pressures. Combustion and Flame, 161(10):2678–2691, 2014. doi: 10.1016/j.combustflame.2014.04.012.
[14] Z.L.Wei, C.W. Leung, C.S. Cheung, and Z.H. Huang. Effects of H 2 andCO 2 addition on the heat transfer characteristics of laminar premixed biogas-hydrogen Bunsen flame. International Journal of Heat Mass Transfer, 98:359–366, 2016. doi: 10.1016/j.ijheatmasstransfer.2016.02.064.
[15] A. Mameri and F. Tabet. Numerical investigation of counter-flow diffusion flame of biogas-hydrogen blends: Effects of biogas composition, hydrogen enrichment and scalar dissipation rate on flame structure and emissions. International Journal of Hydrogen Energy, 41 (3):2011–2022, 2016. doi: 10.1016/j.ijhydene.2015.11.035.
[16] X. Li, S. Xie, J. Zhang, T. Li, and X. Wang. Combustion characteristics of non-premixed CH 4/CO 2 jet flames in coflow air at normal and elevated temperatures. Energy, 214:118981, 2021. doi: 10.1016/j.energy.2020.118981.
[17] A.V. Prabhu, A. Avinash, K. Brindhadevi, and A. Pugazhendhi. Performance and emission evaluation of dual fuel CI engine using preheated biogas-air mixture. Science of The Total Environment, 754:142389, 2021. doi: 10.1016/j.scitotenv.2020.142389.
[18] M.H. Moghadasi, R. Riazi, S. Tabejamaat, and A. Mardani. Effects of preheating and CO 2 dilution on Oxy-MILD combustion of natural gas. Journal of Energy Resources Technology, 141(12):12200, 2019. doi: 10.1115/1.4043823.
[19] A. Harish, H.R. Rakesh Ranga, A. Babu, and V. Raghavan. Experimental study of the flame characteristics and stability regimes of biogas – air cross flow non-premixed flames. Fuel, 223:334–343, 2018. doi: 10.1016/j.fuel.2018.03.055.
[20] G. Tsatsaronis, T. Morosuk, D. Koch, and M. Sorgenfrei. Understanding the thermodynamic inefficiencies in combustion processes. Energy, 62:3–11, 2013. doi: 10.1016/j.energy.2013.04.075.
[21] A. Datta. Entropy generation in a confined laminar diffusion flame. Combustion Science and Technology, 159(1):39–56, 2000. doi: 10.1080/00102200008935776.
[22] K.M. Saqr and M.A. Wahid. Entropy generation in turbulent swirl-stabilized flame: Effect of hydrogen enrichment. Applied Mechanics and Materials, 388:280–284, 2013. doi: 10.4028/www.scientific.net/AMM.388.280.
[23] H.R. Arjmandi and E. Amani. A numerical investigation of the entropy generation in and thermodynamic optimization of a combustion chamber. Energy, 81:706–718, 2015. doi: 10.1016/j.energy.2014.12.077.
[24] A.M. Briones, A. Mukhopadhyay, and S.K. Aggarwal. Analysis of entropy generation in hydrogen-enriched methane–air propagating triple flames. International Journal of Hydrogen Energy, 34(2):1074–1083, 2009. doi: 10.1016/j.ijhydene.2008.09.103.
[25] K. Nishida, T. Takagi, and S. Kinoshita. Analysis of entropy generation and exergy loss during combustion. Proceedings of the Combustion Institute, 29(1):869–874, 2002. doi: 10.1016/S1540-7489 (02)80111-0.
[26] W. Wang, Z. Zuo, J. Liu, and W. Yang. Entropy generation analysis of fuel premixed CH 4/H 2/air flames using multistep kinetics. International Journal of Hydrogen Energy, 41(45):20744–20752, 2016. doi: 10.1016/j.ijhydene.2016.08.103.
[27] R.S. Barlow, N.S.A. Smith, J.Y. Chen, and R.W. Bilger. Nitric oxide formation in dilute hydrogen jet flames: isolation of the effects of radiation and turbulence–chemistry sub models. Combustion and Flame, 117(1-2):4–31, 1999. doi: 10.1016/S0010-2180(98)00071-6.
[28] J.O. Hirschfelder, C.F. Curtiss, and R.B. Bird. Molecular Theory of Gases and Liquids. Wiley, New York, 1954.
[29] K.K.Y. Kuo. Principles of Combustion. Wiley, New York, 1986.
[30] C.T. Bowman, R.K. Hanson, D.F. Davidson, W.C. Gardiner, Jr., V. Lissianski, G.P. Smith, D.M. Golden, M. Frenklach, and M. Goldenberg. GRI_Mech 2.11. Available: http://combustion.berkeley.edu/gri-mech/new21/version21/text21.html.
[31] D.N. Pope, V. Raghavan, and G. Gogos. Gas-phase entropy generation during transient methanol droplet combustion. International Journal of Thermal Sciences, 49(7):1288–1302, 2010. doi: 10.1016/j.ijthermalsci.2010.02.012.
[32] A.V. Mokhov, B.A.V Bennett, H.B. Levinsky, and M.D. Smooke. Experimental and computational study of C 2H 2 and CO in a laminar axisymmetric methane-air diffusion flame. Proceedings of the Combustion Institute, 31(1):997–1004, 2007. doi: 10.1016/j.proci.2006.08.094.
[33] J. Lim, J. Gore, and R. Viskanta. A study of the effects of air preheat on the structure of methane/air counterflow diffusion flames. Combustion and Flame, 121(1-2):262–274, 2000. doi: 10.1016/S0010-2180(99)00137-6.
[34] H.S. Zhen, J. Miao, C.W. Leung, C.S. Cheung, and Z.H. Huang. A study on the effects of air preheat on the combustion and heat transfer characteristics of Bunsen flames. Fuel, 184:50–58, 2016. doi: 10.1016/j.fuel.2016.07.007.
[35] C.J. Sung, J.B. Liu, and C.K. Law. Structural response of counterflow diffusion flames to strain rate variations. Combustion and Flame, 102(4):481–492, 1995. doi: 10.1016/0010-2180(95)00041-4.
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Authors and Affiliations

R. Nivethana Kumar
1
S. Muthu Kumaran
1
Vasudevan Raghavan
1

  1. Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai – 600036, India
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Abstract

Currently, the distribution system has been adapted to include a variety of Distributed Energy Resources (DERs). Maximum benefits can be extracted from the distribution system with high penetration of DERs by transforming it into a sustainable, isolated microgrid. The key aspects to be addressed for this transformation are the determination of the slack bus and assurance of reliable supply to the prioritized loads even during contingency. This paper explores the possibilities of transforming the existing distribution system into a sustainable isolated network by determining the slack bus and the optimal locations and capacity of Distributed Generators (DGs) in the isolated network, taking into account the contingencies due to faults in the network. A combined sensitivity index is formulated to determine the most sensitive buses for DG placement. Further, the reliability based on the loss of load in the isolated system when a fault occurs is evaluated, and the modifications required in for reliability improvement are discussed. The supremacy of the transformed isolated network with distributed generators is comprehended by comparing the results from conventional IEEE 33-bus grid connected test system and modified IEEE 33-bus isolated test system having no interconnection with the main grid.

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Authors and Affiliations

R. Hari Kumar
N. Mayadevi
V.P. Mini
S. Ushakumari

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