شبیه‌سازی جریان گذرای دوفازی در یک پمپ گریز از مرکز در بازه زمانی راه‌اندازی و بررسی پارامترهای مؤثر بر عملکرد پمپ

نوع مقاله : مقاله پژوهشی

نویسندگان

1 عضو هیات علمی / گروه مهندسی مکانیک، دانشکده فنی و مهندسی، دانشگاه ولی عصر(عج) رفسنجان

2 کارشناسی ارشد / گروه مهندسی مکانیک، دانشکده فنی و مهندسی، دانشگاه ولی عصر(عج) رفسنجان

چکیده

پمپ‌های گریز از مرکز در اکثر صنایع وظیفه جابه‌جایی سیالات را به عهده داشته و سهم     قابل­توجهی در میزان انرژی مصرفی دارند. یکی از مسائل حائز اهمیت در تبیین پمپ‌های گریز از مرکز، مرحله­ی راه­اندازی آن است. در این مرحله پمپ به‌صورت گذرا عمل می­کند. بازه­ی زمانی که لازم است تا سرعت چرخشی پمپ به حالت دائمی برسد را بازه­ راه اندازی پمپ می­گویند. در مرحله­ی راه­اندازی، ممکن است به علت ایجاد نوسانات فشار، تجهیزات هیدرولیکی دچار آسیب گردند. بنابراین مطالعه­ی  عملکرد پمپ ها در بازه­ی زمانی گذرا امری ضروری بنظر می­رسد. در پروژه­ی حاضر با استفاده از ابزار دینامیک سیالات محاسباتی به بررسی عملکرد پمپ طی بازه­ زمانی راه­اندازی پرداخته شده است. نتایج بدست آمده نشان دهنده این است که در اثر افزایش مدت‌زمان راه اندازی پمپ، بیشینه­ی فشار ایجاد شده در پمپ کاهش می­یابد و با افزایش طول لوله در پایین دست جریان، مقدار فشار ایجاد شده در پمپ افزوده می­شود و در نهایت با افزودن مقداری مشخص ناخالصی به آب و اجرای تحلیل جریان دو فازی، بیشنه توان مورد نیاز پمپ افزایش می‌یابد.

کلیدواژه‌ها


عنوان مقاله [English]

Simulation of transient two phase flow in the centrifugal pump during start up time and evaluation of effective parameters on the performance of the pump

نویسندگان [English]

  • Mohammad Shafiey Dehaj 1
  • Mohammad Ali Mollaee 2
  • Behrad Haghighi 1
1 Assistant Professor, Department of Mechanical Engineering, Faculty of Engineering, Vali-e-Asr University of Rafsanjan
2 Master Science, Department of Mechanical Engineering, Faculty of Engineering, Vali-e-Asr University of Rafsanjan
چکیده [English]

Centrifugal pumps in most industries are responsible for transporting fluids and significant role in the amount of energy consumed. One of the most important issues in explaining centrifugal pumps is the start-up stage. As this point, the pump performs at transient mode. The period when it is necessary for the pump to rotate at a constant speed is called the start-up time of the pump. All the start-up stage, hydraulic equipment may be damaged due to pressure fluctuations. Therefore, it seems necessary to study the performance of the pump at transient stage. In the present study, using the computational fluid dynamics tools, the performance of the pump during the start-up period has been studied. The result show that due to the increase in pump start-up time, the maximum pressure created in pump decreases. And by increasing the length of the pipe downstream, the amount of pressure created in the pump increases. Finally, by adding a certain amount of impurities to the water and performing a two-phase flow analysis, the power required by the pump increases.

کلیدواژه‌ها [English]

  • centrifugal pump
  • numerical simulation
  • Startup period
  • Computational fluid dynamics
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