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Flow Aeration after Gate in Bottom Outlet Tunnels

  • Research Article - Civil Engineering
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Abstract

Bottom outlet tunnels are among the most important structures of dam design processes and operation which are encountered with many dangerous problems. This study investigating the flow aeration between emergency and service gates along the bottom tunnel using a large enough physical model of Karun IV Dam bottom outlet. To do so, performance of 12 alternatives was tested to select the best design. Flow characteristics of each alternative have been studied and critical design criteria in view of occurring cavitation hazard has been evaluated. Cavitation indices were calculated along the tunnel from the entrance of the intake to the outlet structure. To eliminate the probability of cavitation hazard, aerators have been designed. Results showed that cavitation hazard was not considerable along the tunnel and installation of aerators between service and emergency gates could definitely diminish the probability of cavitation. Measurements demonstrated that in 60 % opening of service gate the amount of air was maximum by value of 0.024 cm.

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Authors and Affiliations

  1. Hydraulic Structures Division, Water Research Institute, Tehran, Iran

    M. Abdolahpour & R. Roshan

Authors
  1. M. Abdolahpour
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  2. R. Roshan
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Correspondence to M. Abdolahpour.

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Abdolahpour, M., Roshan, R. Flow Aeration after Gate in Bottom Outlet Tunnels. Arab J Sci Eng 39, 3441–3448 (2014). https://doi.org/10.1007/s13369-014-0954-5

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  • DOI: https://doi.org/10.1007/s13369-014-0954-5

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