Abstract




 
   

IJE TRANSACTIONS C: Aspects Vol. 28, No. 3 (March 2015) 360-367   

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  PREDICTING SHEAR STRESS DISTRIBUTION IN RECTANGULAR CHANNELS USING ENTROPY CONCEPT
 
H. Bonakdari, M. Tooshmalani and Z. Sheikh
 
( Received: August 16, 2014 – Accepted: December 18, 2014 )
 
 

Abstract    This study makes use of the Tsallis entropy to predict the shear stress distribution. Given a definition of the Tsallis entropy, it is maximized by using the probability density function, which then is used to attain a novel shear stress equation. This is then employed for calculating the shear stress distribution in rectangular channels in different aspect ratios and finally, for viability, these calculations are compared with some relevant experimental results. This derived shear stress equation is capable of describing the variation of shear stress in both the wall and the bed of channels. The comparison shows that this equation appears to be efficient for predicting the shear stress distribution in rectangular open channels. Mean values of the bed and wall shear stress calculated by the proposed equation have good agreement with the experiments. The shear force percentage calculated from the equation is in good accordance with the experimental measurements.

 

Keywords    Tsallis enropy, open channel, shear force, channel wall, channel bed

 

چکیده    این مطالعه با استفاده از آنتروپی تسالیس به پیش بینی توزیع تنش برشی می پردازد. تعریف آنتروپی تسالیس ارائه می شود و با استفاده از تابع چگالی احتمال، ماکزیمم شده تا بکمک آن یک معادله جدید برای محاسبه تنش برشی ارائه گردد. سپس توزیع تنش برشی در کانالهای مستطیلی با نسبت ابعاد مختلف محاسبه شده و این محاسبات با نتایج آزمایشگاهی مرتبط مقایسه می شود. معادله تنش برشی حاصله قادر به محاسبه توزیع تنش برشی در کف و دیواره های کانال می باشد. مقایسه صورت گرفته نشان می دهد که این معادله قادر به پیش بینی توزیع تنش برشی در مقاطع مستطیلی می باشد. مقادیر متوسط تنش برشی کف و دیواره محاسبه شده توسط معادله پیشنهادی، تطابق خوبی با نتایج آزمایشگاهی دارد. درصد نیروی برشی محاسبه شده با معادله پیشنهادی انطباق خوبی با نتایج آزمایشگاهی نشان می دهد.

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