• Ali A. Jazie Al-Khaledy College of engineering\ Al-Qadisiya University
Keywords: viscous flow, aspect ratio, boundary layer separation, wake, bluff body


In chemical technology and power engineering, equipment containing heat exchanging pipes and various cylindrical links immersed into moving fluid was often used. The estimation of the hydrodynamic action on these elements is based on the solution of the plane problem on the flow past a cylinder. In the hydrodynamics of inviscid flow past a body of nonzero thickness, it was assumed that there are regions near the body in which the flow accelerates from the front stagnation point to the midsection and decelerates behind the midsection. According to the Bernoulli theorem, a pressure counter-gradient arises in the deceleration region, which acts both in the outer flow and in the boundary layer. For the inviscid flow, the fluid particles store sufficiently much kinetic energy in the acceleration region to overcome this barrier, but in the frictional flow, the fluidparticles that remain in the boundary layer cannot reach the region of higher pressure. They are pushed away from the wall, and an opposite flow arises downstream. This phenomenon is known as the boundary layer separation. A CFD models were simulated for the viscous flow past bodies changed from a circular cylinder to flat plate. FLUENT 6.3.26 package was used for solving the model preprocessed in GAMBIT 2.3.16 for flow past a body. Fluent solvers were based on the finite volume method and general conservation (transport) equation for momentum was discretized into algebraic equations. The pressure and velocity gradients for viscous flow past bodies changed from a circular cylinder to flat plate was predicted and plotted and the effect of eccentricity on the pressure and velocity gradients was studied.


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How to Cite
A. Jazie Al-Khaledy, A. (2017). EFFECT OF ECCENTRICITY ON THE PRESSURE AND VELOCITY GRADIENTS ALONG A STREAMLINE PAST A CYLINDERICAL BODY. Al-Qadisiyah Journal for Engineering Sciences, 2(2), 459-476. Retrieved from http://qu.edu.iq/journaleng/index.php/JQES/article/view/76