مقایسه دو مدل برای انتقال برماید در ستون‌های خاک دست نخورده با مدل کسری انتقال-پخش

نوع مقاله: مقاله پژوهشی

نویسندگان

1 استادیار دانشگاه آزاد اسلامی واحد علوم و تحقیقات آذربایجان شرقی، گروه علوم ومهندسی آب، تبریز، ایران

2 استادیار دانشگاه آزاد اسلامی واحد علوم و تحقیقات تهران

3 دانش آموخته کارشناسی ارشد دانشگاه تبریز

چکیده

امروزه استفاده از مدل‌های ریاضی به عنوان ابزاری کارآمد در مطالعات و مدیریت انتقال جرم در محیط‌های متخلخل رایج می‌باشد. در این مطالعه از رابطه توسعه یافته و اصلاح شده انتقال-پخش (ADE)، تحت عنوان رابطه کسری انتقال-پخش (FADE) که براساس تئوری حرکت لوی بنا شده است برای شبیه‌سازی انتقال برماید در ستون‌های خاک دست نخورده لوم رسی و لوم شنی (به طول 40 سانتی­متر و قطر 10 سانتی­متر) استفاده گردید. مقادیر درجه کسری (α) برای دو ستون خاک لوم رسی و لوم شنی همواره کمتر از دو و بترتیب برابر 437/1 و 865/1 بدست آمد. این نشان داد که انتقال برماید در ستون‌های خاک دست نخورده لوم رسی و لوم شنی بصورت انتقال نامتعارف یا انتقال غیرفیکی بوده و مدل کسری انتقال-پخش، نسبت به مدل انتقال-پخش که براساس قانون انتشار فیکی بنا شده است کارآمدتر بوده و برای شبیه‌سازی برماید در ستون‌های خاک دست نخورده لوم رسی و لوم شنی توصیه می‌گردد. بررسی­های نموداری و آماری نیز کارآیی مدل FADE را در شبیه­سازی انتقال برماید تائید کردند. علی­رغم دقت بالای مدل کسری انتقال-پخش در این تحقیق، در کل تفاوت عمده­ای بین دو مدل FADE و ADE مشاهده نگردید.

کلیدواژه‌ها


عنوان مقاله [English]

Modeling of Bromide Transport in Undisturbed Soil Columns with Fractional Advection-Dispersion Equation (FADE)

نویسندگان [English]

  • Sh. Shahmohammadi Kalalagh 1
  • H. Babazadeh 2
  • S. Bahari 3
1 Assistant professor, Department of Water Sciences and Engineering, East Azarbaijan Science and Research Branch, Islamic Azad University, Tabriz, Iran
2 Research Branch, Islamic Azad University, Tabriz, Iran
3 Former M.Sc student, Tabriz University
چکیده [English]

Nowadays, mathematical models are commonly used as efficient tools in solute transport studies and management in porous media. In this study, the developed and improved Advection-Dispersion Equation (ADE) model known as Fractional Advection-Dispersion Equation (FADE), which is based on the theory of Levy motion, was used to simulate the transport of bromide through undisturbed clay loam and sandy loam soil columns (10 cm in diameter and 40 cm long). The quantities of fractional order (α) for clay loam and sandy loam soil columns were derived at 1.437 and 1.865 (less than 2), respectively. This indicated that the bromide transport behaviour within the clay loam and sandy loam soil columns was anomalous transport or non-Fickian transport and FADE model was more suitable for simulation of bromide transport through undisturbed clay loam and sandy soil columns compared to ADE model with Fickian diffusion law basis. The graphical and statistical analysis confirmed the efficiency of FADE model for simulation of bromide transport. Despite high accuracy of FADE model in this research, there was no appreciable difference between FADE and ADE models.

کلیدواژه‌ها [English]

  • Anomalous transport
  • Brownian motion
  • Levy motion
  • Fractional order
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