Determination of Stream Tube Dimensions and the Strength of Secondary Circulation at Lateral Intakes

Abstract

In lateral intakes a portion of stream flow which enters the intake is divided from the upstream of the intake and is called stream tube. Past researchers have proved that the amount of flow and sediment discharge entering the intake as well as design of submerged vane to control sediment depends on determination of stream tube dimensions. In this study experimental and numerical investigation of the flow patterns at a 90° open-channel diversion is presented. In the experimental tests three components of velocity data obtained for different flow conditions. Then numerical SSIIM 2 model was calibrated and verified using tests data. More flow conditions were run using SSIIM 2 model to get enough hydraulic data. From analysis of these data it was found that the dividing stream tube dimensions depends upon directly to the ratio of diversion flow discharge to the main flow discharge. The strength of a secondary circulation was found to vary with inverse value of the main channel Froude number. Relations for predicting the stream tube dimensions and the strength of secondary circulations have been presented in this paper.

Keywords

• Lateral intakes
• Stream Tube
• Strength of Secondary Circulations
• SSIIM2 Model
• Flow patterns