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یوسف زاده, شهروز, دوستدار, محمد مهدی, سرلک, رضا. (1401). بررسی اثر میدان مغناطیسی مورب بر جابجایی آزاد نانوسیال در یک محفظه مربعی با دو چشمه حرارتی متغیر. پدافند الکترونیکی و سایبری, 11(1), 173-197.
شهروز یوسف زاده; محمد مهدی دوستدار; رضا سرلک. "بررسی اثر میدان مغناطیسی مورب بر جابجایی آزاد نانوسیال در یک محفظه مربعی با دو چشمه حرارتی متغیر". پدافند الکترونیکی و سایبری, 11, 1, 1401, 173-197.
یوسف زاده, شهروز, دوستدار, محمد مهدی, سرلک, رضا. (1401). 'بررسی اثر میدان مغناطیسی مورب بر جابجایی آزاد نانوسیال در یک محفظه مربعی با دو چشمه حرارتی متغیر', پدافند الکترونیکی و سایبری, 11(1), pp. 173-197.
یوسف زاده, شهروز, دوستدار, محمد مهدی, سرلک, رضا. بررسی اثر میدان مغناطیسی مورب بر جابجایی آزاد نانوسیال در یک محفظه مربعی با دو چشمه حرارتی متغیر. پدافند الکترونیکی و سایبری, 1401; 11(1): 173-197.

بررسی اثر میدان مغناطیسی مورب بر جابجایی آزاد نانوسیال در یک محفظه مربعی با دو چشمه حرارتی متغیر

مکانیک سیالات و آیرودینامیک
دوره 11، شماره 1 - شماره پیاپی 29، شهریور 1401، صفحه 173-197    اصل مقاله (3.79 M)
نوع مقاله: مقاله پژوهشی
نویسندگان
شهروز یوسف زاده* 1؛ محمد مهدی دوستدار2؛ رضا سرلک3
1استادیار، گروه مهندسی مکانیک، واحد الیگودرز، دانشگاه آزاد اسلامی، الیگودرز، ایران
2استاد ، دانشکده فنی و مهندسی دانشگاه جامع امام حسین (ع)، تهران، ایران
3کارشناسی ارشد، گروه مهندسی مکانیک، واحد الیگودرز، دانشگاه آزاد اسلامی، الیگودرز، ایران
تاریخ دریافت: 09 فروردین 1401،  تاریخ بازنگری: 31 تیر 1401،  تاریخ پذیرش: 13 مرداد 1401 
چکیده
در این پژوهش انتقال حرارت جابجایی آزاد برای محفظه مربعی شکل حاوی دو نانوسیال آب-آلومینا و آب-مس که تحت تأثیر میدان مغناطیسی مورب قرار دارد به روش عددی شبیه­سازی شده و تأثیر پارامترهایی مانند عدد رایلی ( )، عـــدد هارتمن ( )، زاویه میدان مغناطیسی ( )، کسر حجــمی نانــوذرات ( )، نوع منبع حرارتی (خطی یا سینوسی)، طول منبع حرارتی ( ) و پارامتر غیریکنواختی چشمه ( )، بر روی میدان‌های جریان و دما مورد مطالعه قرار گرفته‌ است. نتایج به‌دست‌آمده نشان می‌دهند که با افزایش عدد رایلی و عدد هارتمن، میزان انتقال حرارت به ترتیب افزایش و کاهش می‌یابد. همچنین عملکرد حرارتی محفظه با افزایش زاویه میدان مغناطیسی (از 0 تا 90 درجه) بهبود می­یابد و با افزودن نانوذرات جامد به سیال پایه افزایش نسبی انتقال حرارت در محفظه مشاهده می­شود. در اعداد رایلی بالا و پایین، بیشینه انتقال حرارت مربوط به چشمه دما ثابت می‌باشد و پس از آن برای اعداد رایلی بالا چشمه سینوسی با  و برای اعداد رایلی پایین، که انتقال حرارت هدایت بر محفظه حاکم است، چشمه خطی با  دارای بیشترین عدد ناسلت متوسط می‌باشند. با بررسی طول منابع حرارتی می­توان دریافت که با افزایش طول چشمه­ها، میزان انتقال حرارت افزایش می‌یابد.
کلیدواژه‌ها
انتقال حرارت؛ نانوسیال؛ میدان مغناطیسی؛ محفظه مربعی؛ چشمه حرارتی
عنوان مقاله [English]
Effect of Diagonal Magnetic Field on Natural Convection of Nano-Fluid Inside a Square Enclosure with Two Variable Heat Sources
نویسندگان [English]
Shahrouz Yousefzadeh1؛ Mohammad Mehdi - Doustdar-2؛ Reza Sarlak3
1Department of Mechanical Engineering, Aligudarz Branch, Islamic Azad University, Aligudarz, Iran
2Department of Mechanical Engineering, Imam Hossein Univesity ، Tehran ،Iran
3Department of Mechanical Engineering, Aligudarz Branch, Islamic Azad University, Aligudarz, Iran
چکیده [English]
In this research, the natural convection heat transfer for a square enclosure containing two Nano-fluids, water-alumina and water-copper, which is affected by a diagonal magnetic field, is simulated numerically and the effects of some parameters such as Rayleigh number ( ), Hartmann number ( ), magnetic field angle ( ), nanoparticle volume fraction ( ), type of heat source (linear or sine), length of the heat source ( ) and the non-uniformity parameter of the source ( ) have been studied on the flow and temperature fields. The results show that with increasing Rayleigh  number and Hartmann number, the amount of heat transfer increases and decreases, respectively. Also, the thermal performance of the enclosure is improved by increasing the angle of the magnetic field (from 0 to 90 degrees) and by adding solid nanoparticles to the base fluid, it means a relative increment in enclosure heat transfer is observed. In both high and low Rayleigh numbers, the maximum heat transfer is related to the constant temperature source. After that, for high Rayleigh numbers a sinusoidal source (λ = 1) and for low Rayleigh numbers a linear source (λ =0.5), where the conduction heat transfer dominates on enclosure, have the highest average Nusselt number, respectively. The results also indicate that when the length of heat sources increases, the rate of heat transfer increases too.
کلیدواژه‌ها [English]
Heat Transfer, Nano-Fluid, Magnetic Field, Square Enclosure, Heat Source
مراجع
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آمار
تعداد مشاهده مقاله: 76
تعداد دریافت فایل اصل مقاله: 134