شبیه‌سازی عددی سرعت جریان در اطراف پایه‌های پل تکی و دو قلو با چیدمان‌های مختلف با استفاده از مدل فلوئنت

نوع مقاله : مقاله پژوهشی

نویسندگان

1 بخش مهندسی آب، دانشگاه شیراز

2 دانشگاه شیراز

چکیده

ساختار جریان در اطراف پایه پل بسیار پیچیده است. به دلیل شرایط خاص هندسی و سازه­ای برخی موارد ایجاب می‌نماید که پایه­‌ها به صورت دوتایی با چیدمان‌­های خاص کنار یکدیگر قرار گیرند که این امر منجر به پچیده تر شدن ساختار جریان اطراف پایه می­شود. در این پژوهش، تغییرات سرعت جریان و انرژی جنبشی آشفته اطراف تک­پایه و گروه پایه­‌های پل دوتایی با مقطع دایره، در حالتی که پایه‌­ها به سه صورت پشت سر هم، کنار هم و زاویه‌دار نسبت به جهت جریان قرار گرفته‌اند، با استفاده از نرم‌­افزار فلوئنت شبیه‌سازی ‌شده است. مولفه­‌های سه‌­بعدی سرعت، خطوط جریان و خطوط هم­تراز سرعت برای هر دو حالت تک‌پایه و دو پایه بررسی شده‌­اند. با مقایسه مقادیر سرعت طولی بین داده‌­های آزمایشگاهی و شبیه‌­سازی شده در دو مقطع عرضی انتخابی، خطای میانگین برای مدل تک­پایه برابر با 3/7 درصد و برای مدل دو پایه پشت سر هم برابر با 3/54 درصد به­ دست آمد. همچنین مقدار مولفه طولی سرعت در مدل دو پایه پشت سر هم، دو پایه کنار هم و مدل زاویه‌دار نسبت به تک‌پایه به ترتیب  2/34% و  9/27% کاهش و 8/87% افزایش داشته است. به طور کلی، به دلیل وقوع کمینه مقادیر سرعت و انرژی جنبشی آشفته، مناسب‌ترین حالت قرارگیری پایه‌­ها در مسیر جریان به ­صورت کنار هم توصیه می­‌شود.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical simulation of flow velocity around single and twin bridge piers with different arrangements using the Fluent model

نویسندگان [English]

  • Zahra Behrouzi 1
  • Hossein Hamidifar 1
  • Mohammad Ali Zomorodian 2
1 Water Engineering Department, Shiraz University
2 Shiraz University
چکیده [English]

Flow structure around the bridge pier is a very complicated phenomenon. Due to the special geometric and structural conditions in some cases, it is required that the piers be placed in pairs next to each other with special arrangements, which leads to a more complex flow structure around the piers. In this study, the variations of the flow velocity and turbulent kinetic energy around single and twin bridge piers with a circular cross-section are simulated using the Fluent model. The twin piers are placed in three configurations, including tandem, side-by-side, and at inclined with the flow direction. The three-dimensional components of flow velocity, streamlines, and velocity contours have been investigated for both single and twin piers. By comparing the longitudinal velocity between measured and simulated conditions in two selected cross-sections, the average error for the single tandem piers was 7.3% and 3.54%, respectively. Also, the longitudinal velocity in the tandem, side-by-side and inclined piers has decreased by 2.34% and 9.27% ​​and increased by 87.8%, respectively, compared to the single pier conditions. In general, due to the minimum values of turbulent velocity and kinetic energy, the side-by-side model is recommended as the most appropriate arrangement of the piers with respect to the flow direction.

کلیدواژه‌ها [English]

  • Flow pattern
  • velocity
  • bridge pier
  • Simulation
  • Fluent
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