آبشستگي موضعي ناشي از جت هاي ديواره اي سه بعدي مايل

Scour Formation Due to 3D Circular Wall Jets

In this paper the results of 63 experiments about the inclination wall jets are presented. The angle of the jets changed from 0 to 20 degree and the densimetric Froude number of the jet change between 3.9 to 12.8. the tailwater ratio changed between 1.5 to 19. The scour mechanism due to 3D inclined wall jets is investigated. The effect of the jet angle for different values of the tailwater depth ratio and different values of the densimetric Froude number of the jets are studied. By using the densimetric Froude number of the jets, tailwater depth ratio and jet angle appropriate equations for estimating the scour hole dimensions are presented. The results show that by increasing the tailwater depth ratio decreasing of the dimensions of the jets are increased. There is a critical tailwater depth that beyond which by increasing or decreasing the tailwater depth the scour hole depth increases. The critical tailwater depth is increased by increasing the jet angle. In general the scour hole dimensions decreases by increasing the jet angle. Therefore, the inclined jets can be used as a procedure for decreasing the scour hole dimensions.