مطالعه عددی اثر موقعیت فین بر انتقال حرارت جابجایی اجباری درون یک کانال در حالت جریان آشفته

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی مکانیک، واحد پردیس، دانشگاه آزاد اسلامی

2 دانشکده مهندسی مکانیک، واحد پردیس، دانشگاه آزاد اسلامی

چکیده

یکی از روشهای مؤثر برای افزایش انتقال حرارت درون کانالها، استفاده از فینها میباشد. در این پژوهش، پنج هندسه مختلف فین در نظر گرفته شده است؛ نتایج عددی برای متغیرهای حرکت سیال و انتقال حرارت ارائه گردیده است. برای این موضوع، معادالت حاکم بر حرکت سیال و انتقال حرارت، به وسیله روش حجم محدود گسسته و حل شد؛ همچنین برای ارتباط سرعت و فشار از روش سیمپل استفاده شد. مدلسازی آشفتگی با استفاده از مدل آشفتگی صورت گرفت. حساسیت حل عددی نسبت به شبکه محاسباتی و اعتبارسنجی نتایج عددی در مقایسه با نتایج تجربی و عددی سایر پژوهشگران، مقایسه شد. سپس هندسههای در نظر گرفته شده برای فین شامل، مثلث با زوایای مختلف، ذوزنقه , مربع مورد بررسی قرار گرفت. برای این هندسهها، نتایج عددی برای بردار سرعت، فشار، دمای سیال ارائه شده است. در انتهای نتایج انتقال حرارت با تحلیل عدد ناسلت مطالعه شده و مقایسهای میان هندسههای مختلف انجام شده است. مقدار ناسلت محلی در فواصل میان فینها، از 100 الی 150 و در انتهای سطح، به مقدار 100 میل میکند. فین مثلثی با زاویه 60 نسبت به فین 90 درجه ناسلت بیشتری داشته و در مجموع نیز فینهای ذوزنقهای بیشترین مقدار ناسلت را نسبت به سایر فینها داشته است. از بررسی نسبت انتقال حرارت به افت فشار، مشاهده شد که فینهای ذوزنقهای، بهترین عملکرد را دارند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical Investigation of Fin Position Effect on the Forced Convection Heat Transfer Inside a Channel in Turbulent Flow

نویسندگان [English]

  • Majid Alavi Lavsani 1
  • Mohsen Pirmohammadi 2
1 Department od mechanical engineering, pardis branch, islamic azad university
2 mechanical engineering, pardis branch, islamic azad university
چکیده [English]

The using of fins for convection heat transfer enhancement is one of the effective approaches of heat transfer enhancement in a 2 dimensional channels. In this investigation, five different geometries for fins have been considered; numerical results were presented for fluid flow variables and heat transfer. For this purpose, governing equations of fluid flow and heat transfer were discretized with finite volume method; also for linking of velocity and pressure of fluid flow, SIMPLE algorithm was employed. Turbulent flow modelling was applied by turbulent model. Sensitivity of numerical results from computational grid and validation of numerical results were provided in compare of experimental and other numerical investigation. Then, geometries were investigated for fins include of triangle with different angle, trapezoidal and square. For these geometries, numerical results for velocity vector, pressure drop and temperature of fluid have been presented. Finally, heat transfer results were studied with regards to Nusselt number. Triangle fin with angle of 60 degrees respect to angle of 90 degrees has more Nusselt number and trapezoidal fin has much Nusselt number among five studied fins. From the investigation of the heat transfer to pressure drop ratio, it was observed that the trapezoidal fins have the best performance.

کلیدواژه‌ها [English]

  • Heat transfer؛ force convection؛ Fin position
  • Finite volume method
  • Turbulent flow
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