The effect of the vortex barker and stepped chamber hydraulic flow through morning glory spillway

Document Type: Original Article


Department of Civil, Poplar Branch, Islamic Azad University, Fars, Iran.


In recent decades, many dams have been built or are under construction. Due to the high demand for water and soil erosion, increasing the need for dam construction in different regions are quite tangible. In 1900 the number of large dams, did not exceed 50. But in the 1950s to 1986 the number of large dams (over 15 meters), more than 39,000 were counted. The 70s dams has been increasing development of large dams. According to the type of operation and type of project is different. Weirs with different types of works are better than one of these types is the lotus Series. The following morning glory spillway is good substitution of side weir for emptying water from dams. The overflow of a circular opening, a conversion and a vertical circular tunnel under the horizontal (or nearly horizontal) that ultimate. In other words, morning glory spillway is composed of a circular crown that flows a mile or vertical shaft guides. In this study, it is to evaluate the performance of both channel and vortex breaker stepped on several tests with a variety of morning glory spillway with hydraulic vortex breaker and variety of steps ducts. The results showed that after about 100 tests done best through a stair case of 12 stairs and through the vortex breaker with low height and length make 6-tuple Which increases the discharge rate is 23%. It should be noted that increasing the thickness of more than 7% of the radius of the vortex breaker overflow over flow does not have much impact on the increase. Also can be understood that the overflow performance and efficiency with 6 vortex breaker is higher than other runs.


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