مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

مدل‌سازی عددی جریان ورودی به مخزن با بستر خشک با استفاده از الگوریتم پخش‌ موج اصلاح‌شده

نویسندگان
1 دانش آموخته کارشناسی ارشد، گروه مهندسی عمران، دانشگاه سیستان و بلوچستان، زاهدان، ایران
2 عضو هیئت علمی دانشگاه بیرجند
چکیده
در این مقاله از یک مدل پخش موج تغییریافته گودونو برای مدل‌سازی سقوط جریان آزاد آب بروی سطح خشک استفاده می‌گردد. مدل موردنظر یک مدل خوش‌توازن بوده و قادر به رفتار کردن مؤلفه‌های منبع جریان ورودی/خروجی به بستر و هم‌چنین مؤلفه‌های اصطکاک در داخل تفاوت شارهای مجاور روش حجم محدود می‌باشد. علاوه بر این، روش موردنظر از نوعی سرعت تقریبی جدید ریمان برای پخشیدگی بر روی سطح خشک استفاده می‌نماید. در ابتدا جریان ورودی از کف به مخزن به‌صورت جت آزاد مورد بررسی قرار می‌گیرد. سپس ورود جریان آب به حالت سقوط آزاد و از وسط و دو کناره مخزن بر روی سطح خشک شبیه‌سازی می‌گردد. جهت مشخص نمودن اعتبار مدل عددی ارائه‌شده برای فشارهای غیرهیدرواستاتیک، از یک عدد بدون بعد بر اساس سرعت ورودی، طول دهانه و ارتفاع سقوط استفاده گردیده است. نتایج حاصله از روش عددی معرفی‌شده با نتایج حاصله از نرم‌افزار استار سی‌دی که یک نرم‌افزار تجاری حل معادلات ناویر-استوکس است، مقایسه گردیده است. نتایج عددی نشان می‌دهد که الگوی عددی شار موج معرفی‌شده با مؤلفه‌های تقریبی جدید سرعت، قادر به شبیه‌سازی سقوط برای سطح خشک برای محدوده معرفی‌شده عدد بی‌بعد می‌باشد.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Numerical Modeling of Water Influx Falling into an Empty Tank using a Modified Wave Propagation Algorithm

نویسندگان English

Sadegh Moodi 1
Hossein Mahdizadeh 2
1 M.Sc graduated, Civil Engineering Department, University of Sistan and Baluchestan, Zahedan, Iran
2 Faculty member of Birjand University
چکیده English

In this paper a modified Godunov-type wave propagation algorithm is utilised for the modelling of falling water wave over a dry bed. The defined numerical model is well-balanced and is capable to treat the influx/efflux source terms and also the friction term within the flux-differencing of the finite volume neighbouring cells. Additionally, the method employs a rather simple HLLE wave speed for the propagation over dry-state. First the efflux flow from the bed of a reservoir is analyzed. Then, the entrance of falling water wave from the middle and edge sides of the reservoir over a dry bottom is simulated. In order to validate the achieved numerical results for the non-hydrostatic pressure situations a dimensionless number based upon the inflow velocity, the slot length and the falling height is introduced. The obtained results of the defined numerical solver are then compared with the numerical prediction of the STAR-CD which is a commercial Navier-Stokes package. The numerical results demonstrate that the introduced flux-wave solver is able to simulate the falling water waves over the dry-state for a given range of the dimensionless number.

کلیدواژه‌ها English

Numerical Modeling
Wave Propagation Algorithm
Shallow Water Equations
STAR-CD software
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