Experimental Investigation of the Effect of Submerged Cubic Obstacles on The Transverse Wave In A Rectangular Channel

Document Type : Research Paper

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Abstract

Vortex is created when flow possed a group of obstacles such as bridges piers, docks and etc. Transverse wave is created by overlapping the vortex that created behind obstacles and due to adapting of the vortexes frequency with natural frequency, of channel dimension. All experiments in this study are done on a flume with 6m in length, 0.72m in wide and 0.6m in height. As obstacles in the flow were, wooden cubic obstacles. The discharge of flow was equal to 20 lit/s and the regime of flow was sub-critical. In all arrangements by reducing the height of submerged obstacles and increasing their submergence ratio, gradually wave amplitude of type 1 and type2 is reduced and the maximum amplitude was also reduce until it completely disappears. For example, in test No. 1 with 21% submergence any wave was not observed. also the maximum amplitude in the non-submerged situation was more than the submerged sitoation.For example, in test No. 1 the maximum amplitude of wave is type 1 was 4.3 mm, This value reduced to zero in the submerged situation. Finally a relationship is proposed to estimate of amplitude of transverse waves for submerged case.

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References

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Irrigation Sciences and Engineering
Volume 40, 1-1
Special Issue
June 2017
Pages 27-37

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History

  • Receive Date: 08 October 2015
  • Revise Date: 07 June 2017
  • Accept Date: 17 January 2016
  • Publish Date: 01 January 1970

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