THE UNIVERSITY OF TRINIDAD & TOBAGO

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1 THE UNIVERSITY OF TRINIDAD & TOBAGO FINAL ASSESSMENT/EXAMINATIONS APRIL 2014 Course Code and Title: Programme: Date and Time: Duration: HYDRAULICS FLUD2006 BASc. Civil Engineering Wednesday 16 th April, :00am to 12:00 noon 3 HOURS PLEASE READ ALL INSTRUCTIONS CAREFULLY BEFORE YOU BEGIN THIS EXAMINATION Instructions to Candidates 1. This paper has 5 pages and 11 questions. 2. You are required to answer six questions, three (3) questions in Section A and three (3) questions in Section B 3. Please list the questions attempted in the answer booklet, in the order in which they were attempted. 4. Please write your student ID number on each page of the answer booklet. Key Examination Protocol 1. Students please note that academic dishonesty (or cheating) includes but is not limited to plagiarism, collusion, falsification, replication, taking unauthorised notes or devices into an examination, obtaining an unauthorised copy of the examination paper, communicating or trying to communicate with another candidate during the examination, and being a party to impersonation in relation to an examination. 2. The above mentioned and any other actions which compromise the integrity of the academic evaluation process will be fully investigated and addressed in accordance with UTT s academic regulations. 3. Please be reminded that speaking without the Invigilator s permission is NOT allowed. The University of Trinidad & Tobago Page 1 of 5

2 DO EITHER QUESTION #1 OR #2 Question 1 Answer all parts of this question. SECTION A - - (ANSWER 3 QUESTIONS) a) Describe how open channel flow differs from fluid flow in a closed conduit. b) For open channel flow please address: i. The cross sectional shape of the channel. ii. The type of fluid. c) Open channel flow can be produced in two ways. Please describe the two ways and give an example of each. d) Describe how the driving force in open channel flow differs from that for flow in a closed conduit. e) Please give real world examples of open channel flow. Question 2 Answer all parts of this question. How the depth of flow changes with respect to time and location along a channel can be used to determine the classification of flow. Knowing this, please define: (a) Steady flow. (b) Based on the definition of steady flow explain what would need to occur for the equation Q = AV to be true. (c) What is uniform flow? (d) Describe what is a prismatic channel. (e) What is the relationship between steady flow and uniform flow? DO EITHER QUESTION #3 OR #4 Question 3 a) What is the Manning Equation for the S. I. system? Explain each term. (5 marks) b) Water flows in a triangular channel with a right angle at the apex, i.e. 90 o. For n = , and depth of flow of 1.0m and the slope is what is the flow rate? (7.5 marks) c) A rectangular channel is lined with brick (n = 0.016). The width of the channel is 2m and the depth of flow is 3.21m. Calculate the flow rate. (7.5 marks) The University of Trinidad & Tobago Page 2 of 5

3 Question 4 An open channel of trapezoidal cross section, 2.5m at the base and sides inclined at 60 o to the horizontal has a bed slope of 1 in 500. It is found that when the flow is 1.5m 3 /s, the depth of the water in the channel is 0.5m. Assuming the validity of the Manning formula, calculate the flow rate when the depth of flow is 0.7m. DO EITHER QUESTION #5 OR #6 Question 5 In the figure below, the slope of the channel is and n = All side slopes are 1:1. Calculate the flow rate. Question 6 In the Compound channel shown below: For the main channel n = For the flood way (overbank) n = For the entire channel S = The flood level (depth) is 4.0m Calculate the discharge and the velocities in the channel. The University of Trinidad & Tobago Page 3 of 5

4 SECTION B - (ANSWER 3 QUESTIONS) PLEASE NOTE THAT QUESTION #11 IS COMPULSORY DO EITHER QUESTION #7 OR #8 Question 7 (a) (i) Explain how a hydraulic jump occurs. (ii) Give two common examples of a hydraulic jump. (iii) What phenomena accompanies a hydraulic jump? Where can a jump be used to utilize these phenomena. (2.5 marks) (2.5 marks) (5 marks) (b) Label as many points, as you can in the accompanying diagram below, including the axes. (10 marks) Question 8 (a) What are the two types of embankment dams? What is the difference between the two? (b) What are some of the critical features in the design of earthfill dam? Please list as many as you can. (c) What is a spillway and how does it protect a dam? (d) The reservoir (lake) behind a dam stores water for different uses. Please list some of the more common uses. (e) Explain the difference between the operation of a flood control reservoir and reservoir which is used for other purposes. (f) Provide a short discussion of sediment transport and dams. (2 marks) (2 marks) The University of Trinidad & Tobago Page 4 of 5

5 DO EITHER QUESTION #9 OR #10 Question 9 (a) The action of waves on beaches depends on two things. What are they? The two items above can each be of two different types. Please explain. (b) What is coastal defense? This can further be subdivided into two terms to distinguish between the two types of hazards. Please describe these. (c) What is a breakwater? Breakwaters are composed of what kind of units, Please describe.. (d) Describe a seawall and how it functions. (e) Describe what is a culvert. Question 10 a) What instruments can be used to protect against the failure of a dam? b) In order to protect downstream communities, we discussed several strategies. Please discuss these in some detail. c) Why is a Tailings dam such a dangerous structure? d) What is the difference between upstream or downstream control in culvert flow? e) Describe how hydraulics plays a role in On Site Wastewater Treatment System. Question 11 - COMPULSORY a) Define specific energy. Write the equation for specific energy. b) What is critical depth? c) What is the critical velocity? d) Coastal flooding is a special type of flooding, please discuss this statement. e) In addition to instruments, what other actions can be taken to reduce the property damage and loss of life, if a dam fails. END OF EXAMINATION The University of Trinidad & Tobago Page 5 of 5