ارزیابی شبیه‌سازی با رویکرد مرز مشترک در پیش‌بینی نفوذ شوری در آب‌خوان‌های لایه‌بندی ساحلی تحت پمپاژ
محورهای موضوعی : مدیریت محیط زیست
سید سجاد مهدی زاده محلی
1
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فریدون وفایی
2
1 - عضو هیات علمی گروه مهندسی عمران، واحد تهران مرکز، دانشگاه آزاد اسلامی، تهران، ایران.*(مسوول مکاتبات)
2 - دانشیار گروه مهندسی محیط زیست، دانشکده مهندسی عمران، دانشگاه صنعتی خواجه نصیرالدین طوسی، تهران، ایران.
کلید واژه: آب‌خوان لایه‌بندی ساحلی, نفوذ شوری, مرز مشترک, پمپاژ, مدل SHI-SWIM, مدل SEAWAT,
چکیده مقاله :
زمینه و هدف: افزایش جمعیت و رشد فعالیت‌های بشری در نواحی ساحلی، تنش بر آب‌خوان‌های ساحلی را افزایش داده و سبب پیش‌روی آب دریا به سمت آن‌ها شده‌است. مدل‌سازی ریاضی نفوذ شوری با استفاده از دو رویکرد امکان پذیر می‌باشد. در رویکرد مرز مشترک، فصل مشترک تقابل آب شور و شیرین با یک خط نشان داده می‌شود، حال آن‌که در رویکرد جریان اختلاطی، یک ناحیه انتقالی این دو سیال را از هم جدا خواهد نمود. شبیه‌سازی با رویکرد مرز مشترک به علت نیاز به داده‌های ورودی کم‌تر و زمان اجرای بسیار سریع‌تر، بیش‌تر مورد استفاده قرار گرفته، درحالی‌که در مدل‌سازی با رویکرد جریان اختلاطی به علت حل هم‌زمان معادله جریان و معادله پخش و انتقال، جواب‌های دقیق‌تری تولید می‌گردد. روش بررسی: در این تحقیق برای آب‌خوان‌های لایه‌بندی ساحلی که در واقعیت از توزیع بیش‌تری نسبت به آب‌خوان‌های همگن برخوردارند، با استفاده از زبان برنامه‌نویسی فرترن، مدل عددی بر پایه رویکرد مرز مشترک (با نام SHI-SWIM) توسعه داده شده و نتایج مدل، پس از صحت‌سنجی و اعتبار‌بخشی، با مشاهدات آزمایشگاهی و کد عددی SEAWAT (با رویکرد جریان اختلاطی) مقایسه شده‌است. در ادامه، سناریوهای مختلفی برای آب‌خوان لایه‌بندی در مقیاس واقعی و با اعمال چاه پمپاژ تعریف شده و علاوه بر بررسی واکنش آب‌خوان نسبت به این تغییرات، نقاط قوت و محدودیت‌های مدل توسعه داده شده آشکار شده‌است. یافته‌ها: شبیه‌سازی مدل آب‌خوان تحت پمپاژ نشان می‌دهد که مدل SHI-SWIM در حالات کاهش فاصله بین چاه و دریا، نفوذ کامل چاه در آب‌خوان و دبی پمپاژ بالاتر پیش‌بینی دقیق‌تری از شکل گوه شوری داشته است اما پیش‌بینی میزان شوری آب برداشتی از چاه، چندان متناسب با نتایج به‌دست آمده در آزمایشگاه و مدل SEAWAT نبوده است.
Background and Objective: Population growth and scarcity of coastal freshwater resources have increased the stresses on many coastal aquifers, leading to aquifer storage decline and salwater intrusion (SWI). Investigation of coastal aquifers routinely involves the application of SWI models, which can be divided into two categories, namely sharp-interface and dispersive-interface approaches. There is no mixing between freshwater and saltwater at sharp-interface approaches. This makes them computationally more efficient while dispersive-modeling approaches are more numerically challenging, but allow for freshwater-saltwater mixing. Method: Most coastal aquifers comprise overlying sequences of geological strata, resulting in SWI characteristics that may differ significantly to those of homogeneous cases. The layered coastal aquifers have received significantly less attention than the more simplified single-layer case, despite the fact that stratified aquifers are widespread. In this study, a sharp-interface approach (named as SHI-SWIM) was developed using FORTRAN programming code. The model is first validated and then applied for the simulation of sand-tank experiment and field-scale multi-layered aquifers exposed to pumping in order to evaluate the strength and limitation of the developed model. Findings: SHI-SWIM model produced better result for higher pumping rates. Additionally, the results of fully penetrating wells and closer position of well to shoreline matched better with the dispersive modeling outputs. In real cases, where the saltwater may wend a long distance toward the well screen, the sharp-interface modeling weakly matched with the dispersive modeling, specially in terms of well salinities.
Reference
1- Bear, J., 1979. Hydraulics of Groundwater, McGraw-Hill, 569 pp.
2- Abd-Elhamid, H.F., Javadi, A.A., 2011. A density-dependent finite element model for analysis of saltwater intrusion in coastal aquifers. Journal of Hydrology, 401, 259–271.
3- Shi, L., Cui, L., Park, N., Huyakorn, P.S., 2011. Applicability of a sharp-interface model for estimating steady-state salinity at pumping wells-validation against sand-tank experiments. Journal of Contaminant Hydrology, 124, 35-42.
4- Llopis-Albert, C., Pulido-Velazquez, D., 2013. Discussion about the validity of sharp-interface models to deal with seawater intrusion in coastal aquifers. Hydrological Process, 28 (10), 3642-3654.
5- Bear, J., Cheng, A.H.-D., Sorek, S., Ouazar, D., Herrera, I., 1999. Seawater Intrusion in coastal aquifers-concepts, methods and practices. Springer publication 14, 627 pp.
6- Bear, J., Cheng, A.H.-D., 2010. Modeling groundwater flow and contaminant transport, Springer publication, Vol 23, 834p.
7- Dausman, A.M., Langevin, C., Bakker, M., Schaars, F., 2010. A comparison between SWI and SEAWAT- the importance of dispersion, inversion and vertical anisotropy, 21st saltwater intrusion meeting, Portugal, 271-274.
8- Mantoglou, A., Papantoniou, M., Giannoulopoulos, P., 2004. Management of coastal aquifers based on nonlinear optimization and evolutionary algorithms. Journal of Hydrology, 297, 209-28.
9- Pool, M., Carrera, J., 2011. A correction factor to account for mixing in Ghyben-Herzberg and critical pumping rate approximations of seawater intrusion in coastal aquifers. Water Resources Research, 47(5).
10- Ataie-Astiani, B., Hosseinabadi, H.R., Fatemi, E., 2006. Numerical model of transport and contaminant discharge from coastal aquifers into seaward, Iran-Water Resources Research, 2(1). 1-17. (In Persian)
11- Dagan, G., Zeitoun, D.G., 1998. Seawater–freshwater interface in a stratified aquifer of random permeability distribution. Journal of Contaminant Hydrology, 29, 185-203.
12- Bakker, M., 2006. Analytic solutions for interface flow in combined confined and semiconfined, coastal aquifers, Advances in Water Resources, 29(3), 417-425.
13- Fitts, C.R., Godwin, J., Feiner, K., McLane, C., Mullendore, S., 2015. Analytic element modeling of steady interface flow in multilayer aquifers using AnAqSim, Groundwater, 53 (3).
14- Essaid, H.I., 1990. A multilayered sharp-interface model of coupled freshwater and saltwater flow in coastal systems: model development and application. Water Resources Research, 16(7), 1431-1454.
15- Huyakorn, P.S., Wu, Y.S., Park, N.S., 1996. Multiphase approach to the numerical solution of a sharp-interface saltwater intrusion problem. Water Resource Research, 32(1), 93-102.
16- Bakker, M., Schaars, F., Hughes, J.D., Langevin, C.D., and Dausman, A.M., 2013. Documentation of the seawater intrusion (SWI2) package for MODFLOW. U.S. Geological Survey Techniques and Methods, Book 6, Chap. A46, 47 pp.
17- Lu, C., Chen, Y., Zhang, C., Luo, J., 2013. Steady-state freshwater–seawater mixing zone in stratified coastal aquifers. Journal of Hydrology, 505, 24-34.
18- Liu, Y., Mao, X., Chen, J., Barry, D.A., 2013. Influence of a coarse interlayer on seawater intrusion and contaminant migration in coastal aquifers. Hydrological Processes, 28(20), 5162-5175
19- Mehdizadeh, S.S., Werner, A.D., Vafaie, F., Badaruddin, S., 2014. Vertical leakage in sharp-interface seawater intrusion models of layered coastal aquifers, Journal of Hydrology. 519, Part A, 1097-1107.
20- Klute, A., Dirksen, C., 1986. Hydraulic conductivity and diffusivity: laboratory methods, In: Methods of soil analysis, Part 1, Physical and Mineralogical Methods, 2nd ed., Agronomy Monograph, Vol. 9, American Society of Agronomy and Soil Science Society of America, Madison, Wisconsin USA, 687-734.
21- Ataie-Ashtiani, B., 1998. Contaminant transport in coastal aquifers, PhD thesis, University of Queensland, Brisbane, Australia.
22- Fetter, C.W., 2001. Applied Hydrogeology. 4th edition, Prentice Hall Inc., New Jersey, 598 pp.
23- Johnson, A.I., 1966. Compilation of specific yields for various materials. U.S. Geological Survey Open-File Report, Albuquerque, 119 pp.
24- Jakovovic, D., Werner, A.D., Simmons, C.T., 2011. Numerical modeling of saltwater up-coning: Comparison with experimental laboratory observations. Journal of Hydrology, 402, 261-273.
25- Dose, E.J., Stoeckl, L., Houben, G.J., Vacher, H.L., Vassolo, S., Dietrich, J., Himmelsbach, T., 2014. Experiments and modeling of freshwater lenses in layered aquifers: Steady state interface geometry, Journal of Hydrology, 509, 621-630.
26- Bear, J., Dagan, G., 1964. Moving interface in coastal aquifers. Journal of Hydraulics Division, ASCE, Vol. 90 (HY4), 193-215.
27- Mualem, Y., Bear, J., 1974. The shape of the interface in steady flow in a stratified aquifer. Water Resources Research, 10(6), 1207-1215.
28- Goswami, R.R., Clement, T.P., 2007. Laboratory-scale investigation of saltwater intrusion dynamics. Water Resources Research, 43, W04418,
29- Voss, C.I., Souza, W.R., 1987. Variable density flow and solute transport simulation of regional aquifers containing a narrow freshwater-seawater mixing zone. Water Resources Research, 23, 1851-1866.
30- Post, V.E.A., Vandenbohede, A., Werner, A.D., Maimun, Teubner, M.D., 2013. Groundwater ages in coastal aquifers, Advances in Water Resources, 57, 1-11.
_||_Reference
1- Bear, J., 1979. Hydraulics of Groundwater, McGraw-Hill, 569 pp.
2- Abd-Elhamid, H.F., Javadi, A.A., 2011. A density-dependent finite element model for analysis of saltwater intrusion in coastal aquifers. Journal of Hydrology, 401, 259–271.
3- Shi, L., Cui, L., Park, N., Huyakorn, P.S., 2011. Applicability of a sharp-interface model for estimating steady-state salinity at pumping wells-validation against sand-tank experiments. Journal of Contaminant Hydrology, 124, 35-42.
4- Llopis-Albert, C., Pulido-Velazquez, D., 2013. Discussion about the validity of sharp-interface models to deal with seawater intrusion in coastal aquifers. Hydrological Process, 28 (10), 3642-3654.
5- Bear, J., Cheng, A.H.-D., Sorek, S., Ouazar, D., Herrera, I., 1999. Seawater Intrusion in coastal aquifers-concepts, methods and practices. Springer publication 14, 627 pp.
6- Bear, J., Cheng, A.H.-D., 2010. Modeling groundwater flow and contaminant transport, Springer publication, Vol 23, 834p.
7- Dausman, A.M., Langevin, C., Bakker, M., Schaars, F., 2010. A comparison between SWI and SEAWAT- the importance of dispersion, inversion and vertical anisotropy, 21st saltwater intrusion meeting, Portugal, 271-274.
8- Mantoglou, A., Papantoniou, M., Giannoulopoulos, P., 2004. Management of coastal aquifers based on nonlinear optimization and evolutionary algorithms. Journal of Hydrology, 297, 209-28.
9- Pool, M., Carrera, J., 2011. A correction factor to account for mixing in Ghyben-Herzberg and critical pumping rate approximations of seawater intrusion in coastal aquifers. Water Resources Research, 47(5).
10- Ataie-Astiani, B., Hosseinabadi, H.R., Fatemi, E., 2006. Numerical model of transport and contaminant discharge from coastal aquifers into seaward, Iran-Water Resources Research, 2(1). 1-17. (In Persian)
11- Dagan, G., Zeitoun, D.G., 1998. Seawater–freshwater interface in a stratified aquifer of random permeability distribution. Journal of Contaminant Hydrology, 29, 185-203.
12- Bakker, M., 2006. Analytic solutions for interface flow in combined confined and semiconfined, coastal aquifers, Advances in Water Resources, 29(3), 417-425.
13- Fitts, C.R., Godwin, J., Feiner, K., McLane, C., Mullendore, S., 2015. Analytic element modeling of steady interface flow in multilayer aquifers using AnAqSim, Groundwater, 53 (3).
14- Essaid, H.I., 1990. A multilayered sharp-interface model of coupled freshwater and saltwater flow in coastal systems: model development and application. Water Resources Research, 16(7), 1431-1454.
15- Huyakorn, P.S., Wu, Y.S., Park, N.S., 1996. Multiphase approach to the numerical solution of a sharp-interface saltwater intrusion problem. Water Resource Research, 32(1), 93-102.
16- Bakker, M., Schaars, F., Hughes, J.D., Langevin, C.D., and Dausman, A.M., 2013. Documentation of the seawater intrusion (SWI2) package for MODFLOW. U.S. Geological Survey Techniques and Methods, Book 6, Chap. A46, 47 pp.
17- Lu, C., Chen, Y., Zhang, C., Luo, J., 2013. Steady-state freshwater–seawater mixing zone in stratified coastal aquifers. Journal of Hydrology, 505, 24-34.
18- Liu, Y., Mao, X., Chen, J., Barry, D.A., 2013. Influence of a coarse interlayer on seawater intrusion and contaminant migration in coastal aquifers. Hydrological Processes, 28(20), 5162-5175
19- Mehdizadeh, S.S., Werner, A.D., Vafaie, F., Badaruddin, S., 2014. Vertical leakage in sharp-interface seawater intrusion models of layered coastal aquifers, Journal of Hydrology. 519, Part A, 1097-1107.
20- Klute, A., Dirksen, C., 1986. Hydraulic conductivity and diffusivity: laboratory methods, In: Methods of soil analysis, Part 1, Physical and Mineralogical Methods, 2nd ed., Agronomy Monograph, Vol. 9, American Society of Agronomy and Soil Science Society of America, Madison, Wisconsin USA, 687-734.
21- Ataie-Ashtiani, B., 1998. Contaminant transport in coastal aquifers, PhD thesis, University of Queensland, Brisbane, Australia.
22- Fetter, C.W., 2001. Applied Hydrogeology. 4th edition, Prentice Hall Inc., New Jersey, 598 pp.
23- Johnson, A.I., 1966. Compilation of specific yields for various materials. U.S. Geological Survey Open-File Report, Albuquerque, 119 pp.
24- Jakovovic, D., Werner, A.D., Simmons, C.T., 2011. Numerical modeling of saltwater up-coning: Comparison with experimental laboratory observations. Journal of Hydrology, 402, 261-273.
25- Dose, E.J., Stoeckl, L., Houben, G.J., Vacher, H.L., Vassolo, S., Dietrich, J., Himmelsbach, T., 2014. Experiments and modeling of freshwater lenses in layered aquifers: Steady state interface geometry, Journal of Hydrology, 509, 621-630.
26- Bear, J., Dagan, G., 1964. Moving interface in coastal aquifers. Journal of Hydraulics Division, ASCE, Vol. 90 (HY4), 193-215.
27- Mualem, Y., Bear, J., 1974. The shape of the interface in steady flow in a stratified aquifer. Water Resources Research, 10(6), 1207-1215.
28- Goswami, R.R., Clement, T.P., 2007. Laboratory-scale investigation of saltwater intrusion dynamics. Water Resources Research, 43, W04418,
29- Voss, C.I., Souza, W.R., 1987. Variable density flow and solute transport simulation of regional aquifers containing a narrow freshwater-seawater mixing zone. Water Resources Research, 23, 1851-1866.
30- Post, V.E.A., Vandenbohede, A., Werner, A.D., Maimun, Teubner, M.D., 2013. Groundwater ages in coastal aquifers, Advances in Water Resources, 57, 1-11.