کاربرد شمع و صفحات مستغرق در تخلیه رسوبات از مخازن سد‌ها در رسوب‌شویی تحت فشار

نویسندگان

چکیده

در این پژوهش با کارگذاری سازه‌های شمع و صفحات مستغرق در جلوی تخلیه‌کننده تحتانی،‏ تأثیر این سازه‌ها در ایجاد جریان گردابی برای تخلیه رسوبات آزمایش شد. شمع‌ها در فاصله‌های مختلف نسبت به یکدیگر و نسبت به دریچه تخلیه‌کننده تحتانی قرار گرفتند. نتایج نشان داد هرچه شمع‌ها به دریچه نزدیک‌تر باشند حجم رسوب‌شویی افزایش می‌یابد،‏ به طوری که در کمترین فاصله قرارگیری شمع نسبت به دریچه،‏ حجم رسوب‌شویی حدود ??،‏ ??? و??? درصد نسبت به حالت بدون سازه برای ارتفاع سطح آب ??،‏ ?? و ?? سانتی‌متر افزایش نشان داد. صفحات مستغرق نیز در فاصله‌های مختلف از دریچه و در سه زاویه متفاوت نسبت به راستای جریان کار گذاشته شدند. بررسی‌ها نشان داد زمانی که صفحات نسبت به دریچه تحتانی در کمترین فاصله کارگذاری شود و زاویه آن نسبت به راستای جریان کوچکتر باشد،‏ بر شدت جریان گردابی افزوده شده به طوری که حجم رسوب‌شویی برای ارتفاع سطح آب ??،‏ ?? و ?? سانتی‌متر به‌ترتیب ???،‏ ?‎/??? و ?‎/??? درصد افزایش داشته است. به طور کلی،‏ نتایج نشان داد که تغییرات حجم رسوب خارج شده از مخزن در حالت کارگذاری صفحات مستغرق،‏ عملکرد بهتری نسبت به کارگذاری شمع دارد.

کلیدواژه‌ها


عنوان مقاله [English]

Application of pile and submerged vanes to -- ove sediments from dam reservoirs in pressured flushing

نویسندگان [English]

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  • a h
چکیده [English]

This study is carried out with the purpose of developing the effective methods to release sediment out of dam reservoirs. Piles and submerged Vanes are employed in front of bottom outlet to enhance vortex flow and their effects were tested. The piles are embedded in different distances from each other and bottom outlet. The results indicated that Piles performance was improved with minimum distance and the rate of sediments evacuated in the water levels of ??, ?? and ?? cm, were increased about ??, ??? and ???%, respectively. The submerged Vanes were also fixed in different distances from the outlet and three different angles with respect to flow direction. The results showed that when the Vane distance from outlet was minimum and the angle of the Vane was less, the intensity of vortex flow was increased. As a result, the amounts of sediment evacuated in the water levels of ??, ?? and ?? cm, were increased about ???.?, ???.? and ???%, respectively. In general, the results indicated that in releasing sediments from reservoirs the submerged Vanes have better performance than piles.This study is carried out with the purpose of developing the effective methods to release sediment out of dam reservoirs. Piles and submerged Vanes are employed in front of bottom outlet to enhance vortex flow and their effects were tested. The piles are embedded in different distances from each other and bottom outlet. The results indicated that Piles performance was improved with minimum distance and the rate of sediments evacuated in the water levels of ??, ?? and ?? cm, were increased about ??, ??? and ???%, respectively. The submerged Vanes were also fixed in different distances from the outlet and three different angles with respect to flow direction. The results showed that when the Vane distance from outlet was minimum and the angle of the Vane was less, the intensity of vortex flow was increased. As a result, the amounts of sediment evacuated in the water levels of ??, ?? and ?? cm, were increased about ???.?, ???.? and ???%, respectively. In general, the results indicated that in releasing sediments from reservoirs the submerged Vanes have better performance than piles.This study is carried out with the purpose of developing the effective methods to release sediment out of dam reservoirs. Piles and submerged Vanes are employed in front of bottom outlet to enhance vortex flow and their effects were tested. The piles are embedded in different distances from each other and bottom outlet. The results indicated that Piles performance was improved with minimum distance and the rate of sediments evacuated in the water levels of ??, ?? and ?? cm, were increased about ??, ??? and ???%, respectively. The submerged Vanes were also fixed in different distances from the outlet and three different angles with respect to flow direction. The results showed that when the Vane distance from outlet was minimum and the angle of the Vane was less, the intensity of vortex flow was increased. As a result, the amounts of sediment evacuated in the water levels of ??, ?? and ?? cm, were increased about ???.?, ???.? and ???%, respectively. In general, the results indicated that in releasing sediments from reservoirs the submerged Vanes have better performance than piles.This study is carried out with the purpose of developing the effective methods to release sediment out of dam reservoirs. Piles and submerged Vanes are employed in front of bottom outlet to enhance vortex flow and their effects were tested. The piles are embedded in different distances from each other and bottom outlet. The results indicated that Piles performance was improved with minimum distance and the rate of sediments evacuated in the water levels of ??, ?? and ?? cm, were increased about ??, ??? and ???%, respectively. The submerged Vanes were also fixed in different distances from the outlet and three different angles with respect to flow direction. The results showed that when the Vane distance from outlet was minimum and the angle of the Vane was less, the intensity of vortex flow was increased. As a result, the amounts of sediment evacuated in the water levels of ??, ?? and ?? cm, were increased about ???.?, ???.? and ???%, respectively. In general, the results indicated that in releasing sediments from reservoirs the submerged Vanes have better performance than piles.

کلیدواژه‌ها [English]

  • Submerged Vanes-Vortex flow.-Flushing capacity-Bottom outlet-Pile-