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Flow systems most often present thermal, mechanical and chemical losses due to irreversibility during the flowing fluid transport. These losses strongly impact both their energy performances and the flowing fluid quality. In this paper, two effective, drinking water and irrigation, tree-shaped networks (from the fluid quality and energy performance points of view) are constructed by using the constructal approach coupled with the exergy destruction minimization method. It is shown that in the construction of tree-shaped network for water distribution, the method of exergy destruction minimization is equivalent to minimizing mechanical irreversibility (this is equivalent to pumping power) under a water quality constraint. For both phenomena occurring in the network (energy consumption and the fluid quality degradation), this study offers new interesting routes for optimizing the system either by the exergy destruction minimization (in that case, both irreversible processes are taken into account in the design procedure) or by minimizing one of the two irreversible processes, the other being taken into account as the design constraint. The originality of the method relies on the introduction of the environmental protection through the control of the flowing fluid quality. This paper shows that, for the performance improvement of a water distribution network, it is important to focus on the design of the network rather than enhancing only the transport properties. Note finally that the focus on the quality in flow systems is a crucial approach in environmental engineering such as drinking water distribution systems or chemical fluids transfer systems. The approach presented in this paper should be seen as an introduction to reactive flow systems designing by constructal approach.
constructal theory, design, drinking water, exergy, irrigation, water distribution network
[1] Bejan, A., Constructal-theory network of conducting paths for cooling a heat generating volume.
International Journal of Heat Mass Transfer, 40(4), pp. 799–816, 1997. doi: http://dx.doi. org/10.1016/0017-9310(96)00175-5
[2] Azoumah, Y., Mazet, N. & Neveu, P., Constructal network for heat and mass transfer in a solidgas reactive porous medium. International Journal of Heat Mass Transfer, 47(14–16), pp. 2961–2970, 2004. doi: http://dx.doi.org/10.1016/j.ijheatmasstransfer.2004.03.022
[3] Bejan, A. & Lorente, S., Constructal tree-shaped fl ow structures. Applied Thermal Engineering, 27(4), pp. 755–761, 2007. doi: http://dx.doi.org/10.1016/j.applthermaleng.2006.10.008
[4] Bejan, A. & Lorente, S., Design with Constructal Theory, Wiley: Hoboken, 2008. doi: http:// dx.doi.org/10.1002/9780470432709
[5] Kerneïs, A., Nakache, F., Deguin, A. & Feinberg, M., The effects of water residence time on the biological quality in a distribution network. Water Research, 29(7), pp. 1719–1727, 1995. doi: http://dx.doi.org/10.1016/0043-1354(94)00323-Y
[6] Bieupoude, P., Azoumah, Y. & Neveu, P., Environmental optimization of tree-shaped water distribution networks. Presented at the 5th International Conference on Comparing Design in Nature with Science and Engineering, accepted for publication in the Proceedings of the 6th International Conference on Sustainable Water Resources Management, WIT Press: Riverside, California, 2011.
[7] Prigogine, I., Introduction to Thermodynamics of Irreversible Process, Wiley: New York, 1962.
[8] Carlier, M., Hydraulique Générale et appliquée, Eyrolles: Paris, 1972.
[9] Lahiouel, Y., Haddad, A. & Chaoui, K., Evaluation of head losses in fl uid transportation networks. Sciences & Technologie, 23, pp. 89–94, 2005.
[10] Walski, T., Chase, D. & Savic, D., Water Distribution Modeling, Heasted Method, Heasted Press: USA, 2001.
[11] Rossman, L., Clark, R. & Grayman, W.M., Modeling chlorine residual in drinking-water distribution system. Journal of Environmental Engineering, 120(4), pp. 803–820, 1994. doi: http://dx.doi.org/10.1061/(ASCE)0733-9372(1994)120:4(803)
[12] World Health Organization, Guidelines for Drinking-Water Quality, vol. 2, 2nd edn, Health Criteria and Other Supporting Information. WHO, Mastercom/Wiener Verlag, 1996.
[13] Crittenden, J., Trussell, R., Hand, D., Howe, K. & Tchobanoglous, G., Water Treatment, Principles and Design, 2nd edn, John Wiley & Sons: New York, 2005.
[14] Powell, J., Hallam, N., West, J., Forster, C. & Simms, J., Factors which control bulk chlorine decay rates. Water Research, 34(1), pp. 117–126, 2000. doi: http://dx.doi.org/10.1016/S00431354(99)00097-4
[15] Rodriguez, M., Milot, J., Sérodes, J. & Pacaud, A., Estimation of bench-scale chlorine decay in drinking water using nth order kinetic and back propagation neural network models. Water Quality Research, 37(3), pp. 613–635, 2001.
[16] Environmental Protection Agency (EPA), National primary drinking water regulations:
disinfectants and disinfection by products rule; Final rule. Federal Register, 63(241), pp. 69390–69476, 1998.
[17] Torrijos, M. & Moletta, R., Winery wastewater depollution by sequencing batch reactor. Water Science and Technology, 35(1), pp. 249–257, 1997. doi: http://dx.doi.org/10.1016/S02731223(96)00903-1
[18] Montangero, A. et al., Optimising water and phosphorus management in the urban environmental sanitation system of Hanoi. Vietnam Science of the Total Environment, 384(1–3), pp.
55–66, 2007. doi: http://dx.doi.org/10.1016/j.scitotenv.2007.05.032
[19] Zella, L. & Kettab, A., Optimisation d’un réseau de micro-irrigation = Optimising a microirrigation network. Sécheresse, 14(3), pp. 189–194, 2003.
[20] Calejoa, M., Lamaddalenab, N., Teixeirac, J. & Pereirac, L., Performance analysis of pressurized irrigation systems operating on-demand using flow-driven simulation models. Agricultural Water Management, 95(2), pp. 154–162, 2008. doi: http://dx.doi.org/10.1016/j. agwat.2007.09.011
[21] De La Bouëre, J., Micro-irrigation, bases et principes DVD réf MA2602, Lavoisier 2000–2010, 2006.
[22] Delahaye, E., Welté, B., Levi, Y., Leblon, G. & Montiel, A., An ATP-based method for monitoring the microbiological drinking water quality in a distribution network. Water Research, 37(15), pp. 3689–3896, 2003. doi: http://dx.doi.org/10.1016/S0043-1354(03)00288-4
[23] Clarck, R., Rossman, L. & Wymer, L., Modeling distribution system water quality: regulatory implications. Journal of Water Resources Planning and Management, 121(66), pp. 423–428, 1995. doi: http://dx.doi.org/10.1061/(ASCE)0733-9496(1995)121:6(423)
[24] Tondeur, D., Fan, Y. & Luo, L., Constructal optimization of arborescent structures with fl ow singularities. Chemical Engineering Science, 64(18), pp. 3968–3982, 2009. doi: http://dx.doi.org/10.1016/j.ces.2009.05.052