Volume 13, Issue 6 (2013)                   Modares Mechanical Engineering 2013, 13(6): 126-139 | Back to browse issues page

XML Persian Abstract Print


1- ّFaculty of Mechanical Engineering, K. N. Toosi Univ. of Tech.
2- Faculty of Aerospace Engineering, K. N. Toosi University of Technology
3- Faculty of Mechanical Engineering, K. N. Toosi Univ. of Tech.
Abstract:   (2637 Views)
The appearance of swirl in the fluid flow, without any external factors, is named self-rotation. There is no consensus among the researchers on the possibility of self-rotation in sink flow. In the present study, this phenomenon is studied experimentally and numerically. In the experiment, a new setup is proposed and the thymol-blue method is developed for velocity measurement. The experimental results show that the net value of circulation in the flow domain does not increase relative to its inlet value with increasing drain flow rate up to several times of claimed critical value. In other words, self-rotation does not happen in sink flow. In the numerical study, the three-dimension model of the experiment is simulated under the same conditions with the experiment. The simulation results have good agreement with the experiment ones and show that the self-rotation does not occur. In addition, the numerical results show that the swirl, or corresponding circulation, which was seen in the experiment, is due to asymmetry of input flow and by eliminating this asymmetry, the swirl can be removed completely.
Full-Text [PDF 1480 kb]   (2129 Downloads)    
Article Type: Research Article | Subject: CFD|Experimental Fluid Mechanics & Heat Transfer
Received: 2012/08/11 | Accepted: 2013/01/5 | Published: 2013/07/6