بررسی آزمایشگاهی اثر پوشش گیاهی صلب غیر مستغرق بر انتقال اندازه حرکت در طول کانال مرکب به روش اندازه‌گیری مستقیم

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانش‌آموخته کارشناسی ارشد سازه‌های هیدرولیکی دانشکده مهندسی دریا، دانشگاه علوم و فنون دریایی خرمشهر، خرمشهر، ایران

2 استادیار، گروه عمران سازه های دریایی، دانشکده مهندسی دانشگاه علوم و فنون دریایی خرمشهر، خرمشهر، ایران.

3 گروه مهندسی آبیاری و آبادانی، پردیس کشاورزی و منابع طبیعی، دانشگاه تهران، کرج، ایران.

4 کارشناس مطالعات، شرکت مهندسین مشاور آب و انرژی اروند، اهواز، ایران.

چکیده

در این پژوهش با استفاده از روش اندازه‌گیری مستقیم، نیروی جریان در کانال مرکب با پوشش گیاهی سنجیده شده است. پوشش گیاهی مورد استفاده در این تحقیق از جنس PVC در نظر گرفته شد. پنج قطر متفاوت با مقادیر 20، 25، 30، 40 و 50 میلی‌متر، دو فاصله طولی 12 و 15 سانتی‌متر و دو  فاصله عرضی 6 و 8 سانتی‌متر با توجه به چیدمان‌های منظم و نامنظم و محل قرارگیری پوشش گیاهی به‌عنوان متغیرهای موردبررسی در این پژوهش استفاده گردید. جهت اندازه‌گیری مستقیم نیرو از نوع خاصی از فلوم هیدرولیکی به نام فلوم هیدرولیکی لبه چاقویی استفاده ‌شد. بر اساس نتایج حاصل از آزمایش­ها مشخص گردید با افزایش قطر پوشش گیاهی مقدار نیروی جریان بیشتر شده که این امر به علت افزایش حجم پوشش گیاهی و کاهش سطح مقطع عرضی جریان بوده است. به­علاوه در ارتباط با اثر فواصل طولی و عرضی پوشش گیاهی می‌توان گفت با افزایش این فواصل مقدار نیروی جریان روندی کاهشی داشت که علت این امر را می‌توان کاهش حجم پوشش گیاهی و جریان‌های ثانویه ناشی از آن را عنوان نمود.

کلیدواژه‌ها

عنوان مقاله [English]

Experimental Study of the Effect of non-Submerged Rigid Vegetation on Flow Force in Symmetrical Rectangular Compound Channel by Direct Measurement Method

نویسندگان [English]

  • ّFoad Maturi 1
  • Mehdi Behdarvandi Askar 2
  • Mohammad Ansari Ghojghar 3
  • Ehsan Parsi 4
1 Graduated from Khorramshahr University of Marine Sciences and Technology, Master of Hydraulic Structures, Faculty of Marine Engineering
2 Assistant Professor, Department of Offshore Structures, Faculty of Marine Engineering, Khorramshahr University of Marine Science and Technology, Khorramshahr, Iran.
3 Department of Irrigation and Reclamation Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
4 Study Expert, Arvand Water and Energy Consulting Engineers Company, Ahvaz, Iran.
چکیده [English]

In this research, using direct measurement method, the flow pressure in the composite channel with vegetation has been measured. The vegetation used in this study was made of PVC. Five different diameters with values ​​of 20, 25, 30, 40 and 50 mm, two longitudinal distances of 12 and 15 cm and two transverse distances of 6 and 8 cm according to the regular and irregular arrangement and the location of vegetation as the proposed variables were used in this study. For direct measurement of force, a special type of hydraulic flume called "knife edge hydraulic flume" was used. Based on the results of the experiment, it was found that with increasing vegetation diameter, the flow force increases, which is due to increasing the volume and reduction of the cross-sectional area of the vegetation. In addition, due to the effect of longitudinal and transverse distances of vegetation, it can be said by increasing these distances, the flow force rate showed a decreasing trend. This is due to the reduction of vegetation volume and the secondary flows caused by vegetation cover.

کلیدواژه‌ها [English]

  • Composite channel
  • direct measurement method
  • flow force
  • knife edge flume
  • vegetation

مراجع

Arman, A. Fathi-Moghadam, M. (2012). Study of Stress Distribution in a Compound Rectangular Section. Journal of Irrigation Sciences and Engineering (JISE). Volume 36, Issue 3, Pages 55-66. (In Farsi)
Barbosa B. S. B. (2010), Influence of Vegetation in Compound Channels Under Uniform Flow, Master Thesis, Instituto Suprior Tecnico, University of Lisbon Portugal.
Behdarvandi askar M., Fathi-Moghadam M. and Mousavi Jahromi S. H., (2013), Comparison of Energy method and Momentum in the study of Momentum transfer between sub-sections of a compound section, Journal of Water Resources Engineering, Year 6, Summer, 1-14.
Ebrahimi, N.G., Kashefipour, M., Fathi-Moghadam, M., Ebrahimi, K., Sanei, M. (2008). Laboratory study of the effect of changing the density of branch vegetation on Manning roughness coefficient. Iran-Watershed Management. Vol. 2, No. 3.
Fathi-Moghadam. M., Kashefipour. M., Ebrahimi. N., Emamgholizade S., (2011), Physical and Numerical Modeling of Submerged Vegetation Roughness in rivers and Flood Plains, Journal Hydraulic Engineering ASCE, November, 858-864
Fernandes. J. (2013). Compound channel uniform and non-uniform flows with and without vegetation in the floodplain. PhD thesis, Ph. D. thesis Departamento de Engenharia Civil. Instituto Superior Técnico da Universidade Técnica de Lisboa.
Hamidifar H. and Omid A. (2013), Investigation of the Effect of Submerged and Non-Submerged Vegetation of Flood Zone on Transverse Mixing Coefficient of Pollutants, Scientific Magazine, Volume 10, Number 1, Spring, 13-23.
Ikeda S. and McEwan I., (2009), Flow and sediment transport in compound channels, IAHR Monograph Series.
Lashkar-Ara, B. Fathi-Moghadam, M. (2014). Analysis of Shear Stress in Rectangular Open Channels Using Force Balance Method. Journal of Hydraulics. Volume 9, Issue 3, Pages 33-44.
Liu C., Shan Y., Liu X. Yang K. (2016a) Method for assessing stage-discharge in meandering compound channels. ICE-Water Manage, 169(1), 17–29.
Liu C., Shan Y., Liu X., Yang K. & Liu H. (2016b) The effect of floodplain grass on the flow characteristics of meandering compound channels. Journal of Hydrology, 542, 1-17.
Maturi F. and Behdarvandi Askar m., (2019), Experimental Study of the Effects of Flow Discharge, Diameter and Depth on Shear Stress in a Rectangular Channel with Rigid Unsubmerged Vegetation, Journal of Applied Engineering Sciences, Volume 9(22), 155-160.
Mohsen M., Vali Samani j. M. and Ayoub Zadeh S. A. (2011), Depth Average Velocity Distribution in Compound Channel Despite Vegetation in Floodplain, Scientific Magazine, Volume 8, Number 3, Fall, 63-75.
Rameshwaran P. and Shiono K. (2007). Quasi two-dimensional model for straight overbank flows through emergent vegetation on floodplains, Journal of Hydraulic Research, 45, 302-315.
Shiono K. and Knight D., (1991), Turbulent open channel flow with variable depth across the channel, Journal of Fluid Mechanics, 222, 617-646.
Sun, X. and Shiono, K. (2009). Flow resistance of one-line emergent vegetation along the floodplain edge of a compound open channel, Advances in Water Resources, 32, 3: 430-438.
Terrier B., (2010), Flow characteristics in straight compound channels with vegetation along the main channel, Phd Thesis, Department of Civil Engineering, Loughborough University, UK.
Tominaga A. and Nezu I., (1991), Turbulent structure in compound open-channel flows, Journal of Hydraulic Engineering, 117, 21-41.
Vojoudi Mehrabani, F., Mohammadi, M., Ayyoubzadeh, A., Fernandes, J., Ferreira, R., (2020). Flow behavior in Non-Prismatic Convergent Compound Channel with Submerged Vegetation on Floodplains. Journal of Hydraulics. Volume 15, Issue 1, Pages 97-111.
White, B., and Nepf, H. (2007). Shear instability and coherent structures in shallow flow adjacent to a porous layer, Journal of Fluid Mechanics, 593, 1-32.
تحقیقات آب و خاک ایران
دوره 52، شماره 2
اردیبهشت 1400
صفحه 439-450

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