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مدلسازی و بررسی آزمایشگاهی کاهش تبخیر سطحی آب توسط پوششهای شناور با حضور جریان سطحی | ||
نشریه مهندسی مکانیک امیرکبیر | ||
مقاله 18، دوره 52، شماره 7، مهر 1399، صفحه 1193-2010 اصل مقاله (1.65 M) | ||
نوع مقاله: مقاله پژوهشی | ||
شناسه دیجیتال (DOI): 10.22060/mej.2019.15515.6145 | ||
نویسندگان | ||
امیر رضازاده1؛ پوریا اکبرزاده* 2؛ میلاد امینزاده3 | ||
1دانشگاه صنعتی شاهرود-دانشکده مهندسی مکانیک | ||
2دانشکده مهندسی مکانیک و مکاترونیک، دانشگاه صنعتی شاهرود، شاهرود، ایران | ||
3دانشکده مهندسی عمران، دانشگاه صنعتی اصفهان، اصفهان، ایران | ||
چکیده | ||
امروزه حفظ منابع آب شیرین بهدلیل رشد جمعیت، تغییرات اقلیمی و خشکسالی از اهمیت ویژهای برخوردار است.در نواحی خشک، بخش قابلتوجهی از آبهای ذخیرهشده بهدلیل تبخیرازبین میروند که پوشاندن سطح مخازن با اجسام شناور، راهکاری ساده و قابلاطمینان برای کاهش تبخیر بهشمار میآید. علیرغم مطالعات گسترده روی پوششهای شناور، تاثیر آنها درحضور جریانهای سطحی تاکنون مورد بررسی دقیق قرار نگرفته است. لذا در این مطالعه به مدلسازی و بررسی آزمایشگاهی تاثیر جریان سطحی بر میزان تبخیر مخازن آب پوشیده با اجسام شناور پرداخته میشود. بدینمنظور از توپهای سیاه و سفید برای پوششدهی مخزن واز یک پمپ جهت ایجاد جریان سطحی ً با استفادهشده است. نتایج آزمایشها نشان میدهد که میزان تبخیر تا یک دبی مشخص (دبی بهینه)، کاهش و مجددا افزایش دبی، افزایش مییابد.همچنین در تمامی شرایط وجود/عدم وجود جریان، کمترین میزان تبخیر در پوششدهی با توپهای سفید رخ میدهد. درضمن پوششدهی بهصورت مخلوطی مساوی از توپهای سیاهو سفید و پوشش با توپهایسیاهبهترتیبدررتبههایبعدیکاهشتبخیرقراردارند (بیشترینتبخیرمربوطبهحالت بدونپوشش میباشد(. همچنین نتایج حاصل از مدلسازی انرژی نشان میدهد که روابط حاکم برمدلسازی،دقت قابلقبولی در تخمین میزان تبخیربرای تمامی حالتهای بدونپوشش/پوششدهی همراه با وجود/عدموجود جریانسطحی خواهد داشت. | ||
کلیدواژهها | ||
تبخیر سطحی؛ جریان سطحی؛ توپهای شناور؛ دبی بهینه؛ بالانس انرژی | ||
عنوان مقاله [English] | ||
Modelling and Experimental Investigation of the Evaporation Suppression Using Floating Covers in the Presence of Surface Flows | ||
نویسندگان [English] | ||
amir rezzazadeh1؛ Pooria Akbarzadeh2؛ Milad Aminzadeh3 | ||
1Department of Mechanical and Mechatronics Engineering, Shahrood University of Technology, Shahrood | ||
2Department of Mechanical and Mechatronics Engineering, Shahrood University of Technology, Shahrood | ||
3Department of Civil Engineering, Isfahan University of Technology, Isfahan, Iran | ||
چکیده [English] | ||
The increase in fresh-water demand due to the rapid population growth and climate changes with severe droughts highlights the protection of limited fresh-water resources. In arid regions, evaporation accounts for a significant fraction of losses from water reservoirs. Among different methods for suppressing evaporative loss, the use of modular floating elements offers a simple and reliable technique. Despite numerous studies on application of floating elements, performance of this method in the presence of surface flows is not yet addressed comprehensively. Hence, the present study aims to investigate the effect of surface flows on evaporation from covered reservoirs. For this purpose, a 500-liter water reservoir was covered with white and black balls and a water-pump provided surface flows at different rates. The results show that evaporation decreases monotonically with increasing surface flow rate until a specific flow rate, called optimal flow rate. The increase in surface flow more than this optimal rate results in increase in evaporative loss. Regardless of surface flow condition, the results indicate that the lowest water evaporation occurs for the coverage with white balls while coverage using a mixture of black and white balls and only with black balls showed higher evaporation rates, respectively (the highest evaporation is of course for the uncovered surface). The experimental findings demonstrate that surface flows with appropriate rates can effectively enhance evaporation suppression efficiency of floating elements. Comparison of the modeling results with experimental outputs highlights application of the physically-based energy balance model in estimating surface evaporation for covered and uncovered water surfaces with and without surface flow conditions. | ||
کلیدواژهها [English] | ||
Surface water evaporation, Surface flows, Floating balls, Optimal flow rate, Energy balance | ||
سایر فایل های مرتبط با مقاله
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مراجع | ||
[1] M. Aminzadeh, P. Lehmann, D. Or, Evaporation suppression and energy balance of water reservoirs covered with self-assembling floating elements, Hydrology and Earth System Sciences, 22(7) (2018) 4015-4032 [2] I.H. Elsebaie, H. Fouli, M. Amin, Evaporation reduction from open water tanks using palm-frond covers: Effects of tank shape and coverage pattern, KSCE Journal of Civil Engineering, 21(7) (2017) 2977-2983 [3] V.M. Álvarez, A. Baille, J.M. Martínez. Effect of black polyethylene shade covers on the evaporation rate of agricultural reservoirs, Spanish Journal of Agricultural Research, 4(4) (2006) 280-288. [4] P. Schouten, S. Putland, C.J. Lemckert, A.V. Parisi, N. Downs, Alternative methods for the reduction of evaporation: practical exercises for the science classroom, Physics Education, 47(2) (2012) 202-210. [5] F. Helfer, H. Zhang, C. Lemckert, Evaporation reduction by windbreaks: Overview, modelling and efficiency, Urban Water Security Research Alliance Technical Report , (16) (2010) 1-15. [6] S. Assouline, K. Narkis, D. Or, Evaporation suppression from water reservoirs: Efficiency considerations of partial covers, Water Resources Research, 47(7) (2011) 1-8. [7] X. Yao, H. Zhang, C. Lemckert, A. Brook, P. Schouten, Evaporation reduction by suspended and floating covers: overview, modelling and efficiency, Urban Water Security Research Alliance Technical Report, (28) (2010) 1-13. [8] N. Chaudhari, N.D. Chaudhari, Use of thermocol sheet as floating cover to reduce evaporation loss in farm pond, 20th International Conference on Hydraulics, Water Resources and River Engineering, IIT Roorkee, India, (2015). [9] C. Silva, D. González, F. Suárez, An experimental and numerical study of evaporation reduction in a saltgradient solar pond using floating discs, Solar Energy, 142 (2017) 204-214. [10] S. Alam, A.A. AlShaikh, Use of palm fronds as shaded cover for evaporation reduction to improve water storage efficiency, Journal of King Saud University-Engineering Sciences, 25(1) (2013) 55-58. [11] E. Mazaheri, J. Abedi Kupai, Reducing evaporation from water pools using floating coatings, Iranian Journal of Soil and Water Research, 49(3) (2018) 597-605.(in Persian). [12] M.A. Benzaghta, T.A. Mohammed, A.H. Ghazali, M.A.M. Soom, Testing of evaporation reduction methods in humid climates. Proceedings of the Institution of Civil Engineers, 166(4) (2013) 207. [13] S. Assouline, K. Narkis, D. Or, Evaporation from partially covered water surfaces, Water resources research, 46(10) (2010) 1-12. [14] K.R. Cooley, Energy relationships in the design of floating covers for evaporation reduction, Water resources research, 6(3) (1970) 717-727. [15] A. Hassani, Assessment of methods for estimating evaporation rates for the reservoir of Saveh dam (alGhadir), Iranian Water Resources Research, 9(1) (2013) 15-35. (in Persian). [16] S. Ali, N.C. Ghosh, R. Singh, Evaluating best evaporation estimate model for water surface evaporation in semi‐arid region, Hydrological Processes, 22(8) (2008) 1093-1106. [17] A. Gorgizadeh, Determination the uncertainty of evaporation from large dams in subsequent periods under climate change conditions, Shahid Chamran University of Ahvaz, Iran, Master's dissertation, (2014) 22-28. (in Persian). [18] J.R. Masoner, D.I. Stannard, A comparison of methods for estimating open-water evaporation in small wetlands, Wetlands, 30(3) (2010) 513-524. [19] V. Singh, C.Y. Xu, Evaluation and generalization of 13 mass‐transfer equations for determining free water evaporation, Hydrological Processes, 11(3) (1997) 311-323. [20] B. Asmar, P. Ergenzinger, Estimation of evaporation from the Dead Sea, Hydrological Processes, 13(17) (1999) 2743-2750. [21] F. Helfer, H. Zhang, C. Lemckert, Evaporation reduction from farm dams using air-bubble plume destratification, IWA World Congress on Water, Climate and Energy, Dublin-Ireland, (13 May 2012) 13-18. [22] M. Van Dijk, S. Van Vuuren, Destratification induced by bubble plumes as a means to reduce evaporation from open impoundments, Water SA, 35(2) (2009) 157-167. [23] C.W. Cox, Water supply enhancement in Cyprus through evaporation reduction, Massachusetts Institute of Technology,USA, Doctoral dissertation, (1999) 76-87. [24] B. Sherman, C. Lemckert, H. Zhang, The impact of artificial destratification on reservoir evaporation, Urban Water Security Research Alliance Technical Report, 23(4) (2010) 333-350. [25] R. Fernandez, M. Bonansea, A. Cosavella, F.Monarde, M. Ferreyra, J. Bresciano, Technology, Effects of bubbling operations on a thermally stratified reservoir: Implications for water quality amelioration, Water Science and Technology, 66(12) (2012) 2722-2730. [26] M. Fekih, A. Bourabaa, S. Mohamed, Evaluation of two methods for estimation of evaporation from Dams water in arid and semi-arid areas in Algeria, International Journal of Application or Innovation in Engineering & Management, 2(1) (2013) 2319-4847. [27] M.E. Jensen, Estimating evaporation from water surfaces, Proceedings of the CSU/ARS Evapotranspiration Workshop, (15 March 2010)1-27. [28] Z. Xing, L. Chow, F. R. Meng, H.W. Rees, L. Steve, J. Monteith, Validating evapotranspiration equations using Bowen ratio in New Brunswick, Sensors, 8(1) (2008) 412-428. [29] W.C. Swinbank, Long‐wave radiation from clear skies, Quarterly Journal of the Royal Meteorological Society, 89(381) (1963) 339-348. [30] B. Gallego-Elvira, A. Baille, B. Martin-Gorriz, J. Maestre-Valero, V. Martinez-Alvarez, Evaluation of evaporation estimation methods for a covered reservoir in a semi-arid climate (south-eastern Spain), Journal of Hydrology, 458 (2012) 59-67. [31] C. Van Bavel, Potential evaporation: the combination concept and its experimental verification, Water Resources Research, 2(3) (1966) 455-467. [32] M.T. Moreo, A. Swancar, Evaporation from Lake Mead, Nevada and Arizona, March 2010 through February 2012, US Geological Survey Scientific Investigations Report, 40 (2013) 5229. [33] B. Henderson‐Sellers, Calculating the surface energy balance for lake and reservoir modeling: A review, Reviews of Geophysics, 24(3) (1986) 625-649. [34] J.M. Dake, D.R. Harleman, Thermal stratification in lakes: analytical and laboratory studies, Water Resources Research, 5(2) (1969) 484-495. [35] E. Haghighi, D. Or, 2013. Evaporation from porous surfaces into turbulent airflows: coupling eddy characteristics with pore scale vapor diffusion, Water Resources Research, 49(12) (2003), 8432-8442. [36] M. Aminzadeh, D. Or, Energy partitioning dynamics of drying terrestrial surfaces, Journal of Hydrology, 519 (2014) 1257-1270. [37] E. Haghighi, D. Or, Interactions of bluff-body obstacles with turbulent airflows affecting evaporative fluxes from porous surfaces, Journal of Hydrology, 530 (2015) 103-116. | ||
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