Experimental investigation on effects of flow angle at entrance to guide vanes on exiting flow quality | ||
| مدل سازی در مهندسی | ||
| Article 27, Volume 16, Issue 54, October 2018, Pages 361-369 PDF (963.69 K) | ||
| Document Type: Mechanics article | ||
| DOI: 10.22075/jme.2017.5404. | ||
| Author | ||
| mohammad ali ranjbar* | ||
| Khatam-Ol-Anbia(PBU) University, Iran. | ||
| Receive Date: 25 January 2015, Revise Date: 21 April 2017, Accept Date: 27 September 2017 | ||
| Abstract | ||
| To reduce the adverse effects of cross winds on the performance of dry cooling towers in steam power plants, various methods such as installation of guide vanes cascades in wind direction have been used. This experimental investigation aims at evaluating the performance of guide vanes cascades under varying cross wind directions. For this purpose, effects of angle of flow at the entrance to the guide vanes cascade on the exiting flow quality and flow rate through the guide vanes cascade have been investigated using wind tunnel experiments. Results show that at zero degree angle of flow (with respect to the vane surface), the velocity distribution at the cascade outlet is uniform, the vanes' wake is small, and drop in the total pressure is about 2%. Moreover, with increase in the angle of flow at the entrance to guide vanes cascade (in the range 30° to 60°), flow uniformity diminishes and the drop in the total pressure increases, which is indicative of degradation in the performance of the guide vanes cascade. For example, at 60° angle of flow, the guide vanes cascade can only guide 20% of the total flow rate through the cascade. The results further show that for flow angles, at which cross wind strikes the back of the guide vanes cascade, installation of the cascade produces positive effects by changing the flow direction towards the cooling tower radiators, which improves the thermal performance of the radiators. | ||
| Keywords | ||
| Guide Vane; Wind Tunnel; Dry Cooling Tower; Total Pressure Loss; Air Flow rate | ||
| References | ||
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