حل معادلات ضربه قوچ دو بعدی با استفاده از شارموج تغییر یافته و مدل آشفته بالدوین-لوماکس

نوع مقاله : مقاله پژوهشی

نویسنده

دانشگاه بیرجند

چکیده

در این مقاله معادلات جریان غیر ماندگار در لوله ها کشسان در حالت دو بعدی ، توسط یک روش بخش موج گودونف مدل سازی می گردند. مدل عددی ارائه شده در اینجا قادر است ترم های اصطکاک را در داخل تفاوت دو سلول مجاور روش حجم محدود قرار داده و شارموجهای مرتبط با آن را محاسبه نماید. برا ی لحاظ کردن عبارات اصطکاک در اینجا از مدل آشفته بالدوین-لوماکس استفاده می گردد. در ابتدا الگوی عددی برای حل معادلات ضربه قوچ برای یک لوله متصل به مخزن استفاده شده و نتایج عددی حاصل با حل دقیق در دو حالت بدون اصطکاک و همچنین با نظر گرفتن ترم های اصطکاک پایدار مقایسه می گردد.

کلیدواژه‌ها


عنوان مقاله [English]

.Numerical Modelling of Water Hammer Problems based on the Flux Wave Approach and Baldwin-Lomax Turbulence Model

نویسنده [English]

  • Hossein Mahdizadeh
University of Birjand
چکیده [English]

In this paper the two-dimensional unsteady flow within the elastic pipes is modelled based on a Godunov-type wave propagation algorithm. The numerical solver applied herein treats the friction source term within the flux-differencing of the finite volume neighboring cells to calculate the relevant flux-waves. In order to include the unsteady friction term the Baldwin-Lomax turbulence model is utilized. First, the method is examined to model the water hammer problem for a pipe connected to reservoir and the obtained numerical results are compared with the exact solution with both frictionless and steady friction terms. Then, the proposed scheme is employed to simulate the flow within two pipes with different Reynolds number (Re=15800, Re=5800) and the numerical simulations are validated with the available experimental data.

کلیدواژه‌ها [English]

  • Water hammer problem
  • Wave propagation algorithm
  • Flux wave approach
  • Baldwin-Lomax method
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