افزایش راندمان رسوب شویی تحت فشار مخازن با اتصال سازۀ PBC به دریچۀ تخلیۀ رسوب

نوع مقاله: مقاله پژوهشی

نویسندگان

دانشگاه شهید باهنر کرمان

چکیده

رسوب­ گذاری مخازن سدها همواره به­ عنوان یکی از چالش ­های اساسی در استفادۀ پایدار از این سازه­ ها و عامل اصلی از دست رفتن حجم ذخیرۀ آنها مطرح بوده است. یکی از رایج­ ترین تکنیک­های مهندسی برای حفظ ظرفیت ذخیرۀ مخازن، تخلیۀ دوره­ای رسوب با رسوب­ شویی تحت فشار است. مرور منابع علمی مختلف نشان می­ دهد که در حال حاضر راندمان رسوب­ شویی تحت فشار بسیار پایین است. در این مقاله تأثیر استفاده از سازۀ نوع PBC بر راندمان تخلیۀ رسوب در حین رسوب­ شویی تحت فشار به ­صورت آزمایشگاهی بررسی شده است. در این راستا از سازۀ PBCبا چهار قطر و چهار طول نسبی مختلف در مخزن سد استفاده شد. مصالح ماسه­ ای غیرچسبنده با اندازۀ متوسط 0/36 میلی­ متر به ­عنوان رسوب
بستر مخزن در نظر گرفته شد. نتایج بررسی­ ها نشان می­دهد که با کاربرد سازۀ
PBC با مشخصۀ LPBC/Doutlet=5/26 و DPBC/Doutlet=1/32، راندمان رسوب­ شویی در مقایسه با شاهد 4/57 برابر شده ­است. با افزایش طول نسبی سازه، طول و عرض ماکزیمم نسبی مخروط رسوب­ شویی نسبت به شاهد افزایش یافت ولی تغییرات عمق ماکزیمم نسبی ناچیز بود. همچنین، کلیۀ پارامترهای هندسی مخروط رسوب­شویی در قطر بی ­بعد DPBC/Doutlet= 1/32 حداکثر مقدار خود را داشتند.

کلیدواژه‌ها


عنوان مقاله [English]

Improving the Reservoir’s Pressurized Flushing Efficiency by Connecting PBC Structure to the Dam Bottom Outlet

نویسندگان [English]

  • Mohamad Reza Madadi
  • Majid Rahimpour
  • Kourosh Qaderi
Shahid Bahonar University of Kerman
چکیده [English]

Reservoir sedimentation is always known as a serious problem for sustainable use of reservoirs and the main factor of reservoirs storage loss. One of the most common engineering techniques for preserving the reservoirs storage capacity is the periodical desilting of reservoirs by hydraulic flushing. Review of the literature shows that the pressurized flushing operation is currently accomplished with low efficiency. In this paper, the effect of PBC structure on the sediment removal efficiency during pressurized flushing operation was experimentally investigated. In this way, PBC structure with four relative length and four relative diameters were used in the reservoir. Non-cohesive sand particles with D50=0.36 mm were used as the deposited sediments in the reservoir. The results showed that by using the PBC structure with LPBC/Doutlet = 5.26andDPBC/Doutlet = 1.32, the flushing efficiency became 4.57 times more than that of reference test. By increasing the relative length of PBC structure, the maximum relative length and width of flushing cone increased, respectively, compared to the reference test while the variation of the maximum relative depth was negligible. In addition, all the geometric parameters of flushing cone hadtheir maximum values atDPBC/Doutlet = 1.32.

کلیدواژه‌ها [English]

  • Flushing Cone
  • Flushing Efficiency
  • PBC Structure
  • Reservoir Desilting

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