IJE TRANSACTIONS B: Applications Vol. 31, No. 5 (May 2018) 820-825    Article in Press

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B. Ravi Kumar* and M. K. Saranprabhu
( Received: May 07, 2017 – Accepted in Revised Form: March 08, 2018 )

Abstract    In the current study, twin wind blades are designed, fabricated and the effect of various gap ratio (g*) at various angle of attacks (α) on a next to each other twin wind blades are examined in an open-channel wind tunnel. Aerodynamic forces and moments are determined by using three-constraint force balancer. For gap ratio of zero, the aerodynamic attributes are like those of a solitary wind blade edge. As g* increases, these two wind blades actuate the vertical wake to stage vortex shedding modes. With further increment in g*, the wake stream pattern was like those behind a solitary wind blade. For a solitary wind blade, the maximum lift is found to be at α = 30. The pitching moment increases with α. The impact of upper aerofoil blade on the lower one diminished as g* increases.


Keywords    Rotor, Flow characterization, Aerodynamic Performance, CFD Investigation


چکیده    در مطالعه حاضر، تیغه های دوقلو بادی طراحی و ساخته شده اند و اثر نسبت فاصله گشتاور (g *) در زاویه های مختلف حملات (α) در کنار یکدیگر تیغه های دوقلوی باد در یک تونل باد باز کانونی بررسی می شود. نیروها و ممانت آیرودینامیکی با استفاده از سه برابر کننده تعادل نیروی محدود تعیین می شود. برای نسبت شکاف صفر، مشخصه های آیرودینامیک مانند لبه ی تیغه ی انفرادی است. همانطور که g * افزایش می یابد، این دو تیغه باله به سمت عمودی حرکت می کنند تا حالت های انفجار گردابه را کنترل کنند. با افزایش بیشتر در g *، الگوی جریان پی در پی همانند کسانی بود که پشت یک تیغه ی هوای انفرادی بودند. برای یک تیغه ی هوای انفرادی، حداکثر لیفت در α = 30 دیده می شود. لحظه ی پچینگ با α افزایش می یابد. تاثیر تیپ بالایی هواپیما بر روی پایین تر به عنوان g * افزایش می یابد.


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