نوع مقاله: مقاله پژوهشی

نویسندگان

1 فارغ‌التحصیل کارشناسی ارشد مهندسی رودخانه، دانشکده مهندسی دریا، دانشگاه علوم و فنون دریایی خرمشهر.

2 استادیار گروه سازه‌های دریایی، دانشکده مهندسی دریا، دانشگاه علوم و فنون دریایی خرمشهر.

3 دانشیار گروه سازه های آبی، دانشکده مهندسی علوم آب، دانشگاه شهید چمران اهواز.

چکیده

در مطالعه حاضر، انتشار جریان جت سطحی همگرا و شیب­دار روی بستر افقی محیط پذیرنده ساکن و عمیق به­صورت آزمایشگاهی بررسی شده است. بدین منظور از فلوم 6/0×9/0×2/3 متر استفاده گردید. تخلیه­کننده­های سطحی، کانال­های مستطیلی با عرض کف 06/0 متر بودند که در چهار زاویه همگرایی 5/12، 25، 45 و 90 درجه و سه شیب متفاوت صفر، چهار و هشت درصد، سیال جت را مماس بر سطح آب پذیرنده تخلیه نمودند. سیال جت به­صورت محلول آب-نمک در سه دبی متفاوت به محیط پذیرنده­ای با عمق ثابت 7/0 متر تزریق گردید. پس از اجرای آزمایش­ها، تحلیل داده­ها با استفاده از روندیابی تصاویر انجام گردید. مطابق نتایج، رابطه فاصله شعاعی با زمان به­صورت توانی است که توان­های حاصل به­طور متوسط از شیب صفر به هشت درصد افزایش 27 درصدی و از شیب صفر به 4 درصد کاهش هفت درصدی را نشان دادند. ضرایب انتشار نیز برای فواصل شعاعی متوسط، بزرگ و کوچک به ترتیب 4، 2 و 5/4 ارزیابی گردید.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Estimation of Radial Spreading Coefficient of Convergent and Inclined Surface Jet Flow over the Horizontal Bed of a Stagnant Ambient

نویسندگان [English]

  • Tooba Heidari 1
  • Nima Shahni Karamzadeh 2
  • Javad Ahadiyan 3

1 Graduated M.Sc. of River Engineering, Faculty of Sea Engineering, Khorramshahr University of Marine Science and Technology, Iran.

2 Assistant Prof, Faculty of Sea Engineering, Khorramshahr University of Marine Science and Technology, Iran.

3 Associate Prof, Faculty of Water Science Engineering, Shahid Chamran University of Ahvaz. Iran.

چکیده [English]

Desalination plants dispose with the wastewater feed via channels and pipelines. The behavior of dense flows discharged into receiving water body is very important, thus prompting researchers to conducted numerous studies on the behavior of flows from surface and submerged dischargers. Among the scholars focusing on submerged dischargers, Zeitoun et al. (1972), Cipollina et al. (2005), and Bleninger and Jirka (2008) investigated submerged negatively buoyant jets in horizontal, vertical, and oblique discharge conditions and obtained results on flow trajectory and dilution rate. Furthermore, Researchers have also delved into surface dischargers. Using numerical modeling, Kassem et al. (2003) inquired into the effects of different parameters of an outflow, a bed, and receiving ambient water on the properties of dense flows discharged through inclined and divergent channels. Kotsovinos (2000), Papakonstantis and Christodoulou (2010), Kaye and Hunt (2004) experimentally examined the spreading of dense flows caused by the impingement of submerged jets on a horizontal plane. Papakonstantis and Christodoulou (2010) concentrated on negatively buoyant circular jets and vertical and horizontal positively buoyant jets, reporting that the dense flow in negatively buoyant jets and vertical positively buoyant jets has a circular outer boundary. The authors also observed that radial distance from the impingement point to the outer boundary of flow is related to time by a power of 0.5.
As previously stated, understanding the behavior of dense flows discharged into receiving ambient water is highly important. Correspondingly, this study explored the spreading of dense horizontal flow over the bed of deep and stagnant ambient water.

کلیدواژه‌ها [English]

  • Radial spreading coefficient
  • Surface jet
  • Convergence
  • Stagnant ambient
  • Deep ambient

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