Numerical optimization of the mixing flow in a straight tube, single, and two loops helical coil

Wameath Shawqi Abdul-Majeed

Abstract


A great interest of using curved pipes was shown in the industrial applications due to many advantages such as developed agitation which can be obtained as an alternative to the conventional agitation at lower energy consumption and reduced cost. A computational investigations were conducted in this study to contemplate on the enhancement occur in the mixing flow upon using single and multi loops helical coil compared with a straight tube. The objective was to optimize the number of loops in the helical coil. The computations were achieved via “Fluent software” in which 3d, second order upwind were used for all cases studied.  The study consisted of four parts in which the numerical error study was conducted in the first part to optimize the grid meshing and to make sure that the results are independent of it. The effect of using the helical coil on the pressure drop was conducted in the second part. The third and fourth parts of the study were devoted to envisage the enhancement of applying the curved loops in the  coil on the heat and mass transfer, respectively. The main findings of the study were limited effect of single loop coil on the heat and mass transfer processes. Better effect was depicted upon increasing the number of loops in the helical coil into 2. However, applying 2 loops has resulted in building up higher pressure drops. Moreover, the pressure drop was shown slightly higher in the case of applying water when compared with air. 


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References


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