Investigation of Break up Length of free water jet

Document Type : Original Article

Authors

1 Graduated of water structure of shahid chamran University of ahwaz. iran

2 Professor of water structure Eng. of Shahid Chamran University

Abstract

The flow from the dam is a tremendous amount of energy in the absence of energy dissipation, the flow through the irreversible damage to structures downstream of the dam. A one way of dissipating the excess energy is falling jet in the plunge pool. Flow jets in special distance have a dense core which formed of water particles. Much of the pressure on the bed and pool wall is caused by that dense core. After passing some distance, air Intrusion from border and flow turbulence causes to shrinking core and finally it will be vanished. This study examines the failure of the jet length and the parameters affecting it are discussed. Percent from the second to the third experiment the Froude number, approximately 15 % decrease and finally tests the third quarter increased 17 percent compared to 6 percent of the Froude number increases. So we can conclude that the changes failed to increase the jet flow (Froude number) is not constant after reaching a minimum point of the process increases. Further statistical analysis was determined according to the coefficient of expansion Jets in turmoil with the failure probability 0.1 is significant.

Keywords


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