1. How does open channel flow differ from pipe flow?
2. Consider steady fully developed flow in an open channel of rectangular cross section with a constant slope of 5 degree for the bottom surface. Will the slope of the free surface also be 5degree? Explain briefly
3. Water at a temperature of 15degree centigrade is flowing uniformly in a 2m wide rectangular channel with an average flow velocity of 4m/s. if the water depth is 0.5m, determine if the flow is critical, sub-critical or supercritical.
4. During steady and uniform flow through an open channel of uniform cross section, a person claims that the specific energy of the fluid remains constant. A second person claims that the specific energy decreases along the flow due to frictional effects and thus the head loss. With which person do you agree? Explain
5. Water at a temperature of 10 degree centigrade flows in a 6m wide rectangular channel at a depth of 0.55m and a flow rate of 12m3/s. Determine, a) the critical depth, b) whether the flow is subcritical or supercritical and c) the alternate depth
6. A trapezoidal channel made of unfinished concrete lining has a bottom sloped at 1degrees, base with of 5m and a side face slope of 1:1. For a flow rate of 25m3/s, determine the normal depth Yn.
7. Design the best trapezoidal channel to be excavated in firm clay soil with an average slope of 0.0005. The channel is to carry 4m3/s of irrigation water. It is proposed to adopt brick lining for the channel.
8. Consider uniform water flow in a wide channel made of unfinished concrete laid on a slope of 0.0022. Now the water flows over 15cm high bump. If the flow over the bump is exactly critical, determine the flow rate and the flow depth over the bump per unit meter width.
9. Water discharging into 8m wide horizontal rectangular channel from a sluice gate is observed to have undergone a hydraulic jump. The flow depth and velocity before the jump are 1.2m and 9m/s, respectively. Determine a) the flow depth and the Froude's number after the jump, b) the head loss and the dissipation ratio and c) the length of the jump
10. Water flowing in rectangular open channel at a flow rate of 6.64m3/s per meter width is observed to have undergone a hydraulic jump. The flow depth before and after jump were observed to be at 0.5m and 3.6m as shown in the figure. A 2D block (full channel width, into the paper) is observed within the hydraulic jump blocking part of the flow. Determine the drag force (FD) on the block due to the hydraulic jump. (Hint use momentum equation )
11. Describe the reasons for performing dimensional analysis, and outline its limitations.
12. State and describe the three conditions for ensuring complete similarity between model and prototype flow.
13. Consider a liquid in a cylindrical container in which both the container and the liquid are rotating as a rigid body (solid body rotation), the elevation difference between the center of the liquid surface and the rim of the liquid surface h, is a function of angular velocity ω, fluid density ?, gravitational acceleration g, and radius R. Use the method of repeating variables (Buckingham's Pi Theorem) to find a dimensionless relationship between the parameters. Show all your work.
14. Find an expression for the drag force, F on smooth sphere of diameter D, moving with a uniform velocity V in a fluid density Þ and dynamic viscosity µ. Use Rayleigh's method
15. The losses per unit length of pipe ?h/l in turbulent flow through a smooth pipe depend upon velocity V, diameter D, gravity g, dynamic viscosity µ, and density p. With dimensional analysis, determine the general form of the equation.
16. The velocity at a point on a model dam crest was measured to be 2.5m/s. What is the corresponding prototype velocity which is 25 times the model size?
17. The model of an irrigation canal is to be constructed with a model ratio of 1:15. Assuming that water flows through the prototype, work out kinematic viscosity of the fluid in the model if dynamic regarding Reynold's and Froude's numbers is to be satisfied.