# بررسی جریان سیال و انتقال حرارت جابجایی آزاد حفره مربعی با وجود مانع گرم مثلثی با روش المان محدود

نوع مقاله : مقاله مکانیک

نویسنده

دانشکده فنی و مهندسی ، دانشگاه دامغان

چکیده

در این مقاله، انتقال حرارت جابجایی طبیعی در یک حفرۀ مربعی بسته با وجود یک مانع مثلثی گرم در دمای TH، با استفاده از روش المان محدود شبیه سازی شده است. دیواره های بالا و پایین عایق بوده، در حالیکه دیواره های چپ و راست در دمای ثابت Tc (Tc <TH) نگه داشته شده است. روش مورد استفاده با نتایج عددی موجود اعتبار سنجی شده و تطابق بسیار خوبی بین نتایج به دست آمده است. جریان دو بعدی فرض شده و هوا به عنوان سیال عامل در نظر گرفته شده است. تاثیر پارامترهای مختلفی همچون عدد رایلی (Ra=103, 104, 105, 106)، موقعیت مختلف مانع در داخل حفره (H=L=0.1, 0.4, 0.7) و زوایای مختلف مانع (θ=00, 900, 1800, 2700) در نسبت های ابعادی متفاوت مانع (AR=0.2, 0.4, 0.6, 0.8) بر روی جریان سیال و انتقال حرارت داخل کانال بررسی شده است. نتایج نشان می‌دهد که با افزایش عدد رایلی و افزایش نسبت ابعادی، میزان نرخ انتقال حرارت افزایش می یابد. همچنین افزایش فاصله مانع از دیواره های چپ و پایین حفره، منجر به کاهش نرخ انتقال حرارت گشته و بیشترین مقدار عدد ناسلت متوسط به ترتیب در زوایای 0، 90، 270 و 180درجه مشاهده شده است.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

### Natural Convection Fluid Flow and Heat Transfer a Square Cavity with a Heated Triangular Obstacle Using Finite Element Method

نویسنده [English]

• Rasul Mohebbi
Assist. Prof., Mech. Eng., Damghan Univ., Damghan, Iran.
چکیده [English]

In this paper, natural convection heat transfer in a closed square cavity with a hot triangular obstacle at temperature TH simulated by Finite Element Method. The top and the bottom walls are insulated while the left and the right walls are maintained at a constant temperature Tc (TH> Tc). The used method is validated against the existing numerical results and an excellent agreement between the results was found. The flow is assumed to be two-dimensional and air is chosen as a working fluid. The effect of different parameters such as Rayleigh number (Ra =103, 104, 105, 106), different position of obstacle inside cavity (H=L=0.1, 0.4, 0.7) and different angle of obstacle (θ'=00, 900, 1800, 2700) at different aspect ratio (AR =0.2, 0.4, 0.6, 0.8) on fluid flow and heat transfer inside the channel are investigated. The results showed that by increasing the Rayleigh number and increment of aspect ratio, the rate of heat transfer is increased. Also, enhancement the distance of obstacle from left and bottom walls of cavity, lead to decrement rate of heat transfer and the maximum values of mean Nusselt number are shown respectively at angles of 0, 90, 270, 180 degrees.

کلیدواژه‌ها [English]

• Triangular Obstacle
• finite element method
• Natural convection
• Square Cavity

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