1Dept. of Civil Engg., TRR College of Engg., Patancheru, Hyderabad - 502 319, A.P., India.
2Dept. of Civil Engg., JNT University College of Engg., Kukatpally, Hyderabad-500 085, A.P., India.
The steady flow in open channels, when the depth of flow varies gradually with distance, is governed by the classic gradually-varied-flow equation. The solution of this ordinary differential equation allows the tracing of the longitudinal profiles of the water surface of the flow. The hydraulic exponents which form key parameters in the solution of the problem vary with the depth in closed conduits. In this note, a method of evaluation of the hydraulic exponents which vary with depth is proposed for a standard D-shaped tunnel section. The results of the profile computations based on the step-by-step method are compared with the corresponding results of the direct integration method which uses the hydraulic exponents. The results find direct application in hydraulic engineering practice, where flow profile lengths are needed for design purposes.
closed conduit, free surface flow, dynamic equation, hydraulic exponents, gradually varied flow
