Abstract    We present a numerical study of the rotating flow generated by two rotating disks in co-/counter-rotating, inside a fixed cylindrical enclosure similar to the Czochralski configuration (Cz). The enclosure having an aspect ratio A = H/Rc equal to 2, filled with a low Prandtl number fluid (Pr = 0.011), which is submitted to a vertical temperature gradient. The finite volume method has been used to solve numerically the governing equations of the studied phenomenon.We present the steady state flow; and make a comparison between the flow generated by the co-/counter-rotating end disks. This study was caried out for different Richardson numbers; Ri = 0.01, 0.1, 0.5, 1, 2, 3, 5 and 10. The effect of orientation of the magnetic field is also taken into account for different values of the Hartmann number (Ha = 0, 5, 10, 20, 30 and 50). The obtained results show that the strongest stabilisation of the velocity field and heat transfer occurs when the flow generated byco-rotating end disks and the applied of magnetic field in radial direction provied a more stabilisation of the convective flow.

Keywords    Rotating flow, Czochralski, co-/counter-rotating mixed convection, magnetic field

چکیده    ما در حال حاضر، مطالعه عددی جریان چرخشی تولید شده را توسط دو دیسک چرخشی در چرخش همسو/ ناهمسو، در داخل محوطه یک استوانه ثابت مشابه پیکربندی Czochralski (Cz) نشان می دهیم. محوطه دارای نسبت A = H / RC برابر با 2، پر شده با سیالی با عدد پرانتل کوچک (01/0 (Pr = می باشد که به گرادیان دما عمودی نسبت داده می شود. روش حجم محدود برای حل عددی معادلات حاکم پدیده تحت مطالعه استفاده شده است. ما جریان حالت پایدار را ارائه می دهیم؛ و مقایسه ای بین جریان تولید شده توسط دیسک های انتهایی با چرخش همسو/ناهمسو نشان می دهیم. این مطالعه برای عددهای مختلف ریچاردسون Ri برابر با 01/0، 1/0، 5/0، 1، 2، 3، 5 و 10 انجام شد. اثر جهت میدان مغناطیسی نیز برای مقادیر مختلف عدد هارتمن Ha برابر با 0، 5، 10، 20، 30 و 50 به حساب می آید. نتایج به دست آمده نشان می دهد که قوی ترین تثبیت میدان سرعت و انتقال حرارت هنگامی رخ میدهد که جریان، دیسک های انتهایی چرخشbyco تولید می کند و اعمال میدان مغناطیسی در جهت شعاعی، ثبات بیشتری از جریان همرفتی را ایجاد می کند.

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