University of Southern Queensland Faculty of Health, Engineering & Sciences Course Number: ENV2103 Course Name: Hydraulics 1 Assessment No: 1 On-campus  Online  This Assessment carries 150 of the 1000 marks total for this course. Examiner: Justine Baillie Moderator: Dr Malcolm Gillies Assignment: Assignment 2 Date Given: Date Due: Week 1 16 May 2017 Penalty for Late Submission: Loss of all marks for the assessment (See note 3 of assessment information in course specification). Please use *.pdf format only to submit your assignment. Scanned handwritten submissions are acceptable. Each question is marked by a different member of the marking team. Please upload each question as a separate pdf in the relevant submission dropbox. You may upload each individual question at different times as long as it is before the due date. Please use the naming convention: Firstname Lastname QuestionNo.pdf. Do not attach the assignment cover sheet to your uploaded submissions. Your assignment submissions should include appropriate sketches/ annotations, data used, relevant formulas, and any assumptions. Show detailed calculations and working. Give your final answers with the correct number of significant figures and appropriate units. For questions that use your student number as part of the inputs, please clearly state the number used in your submission. Any non USQ copyright material used herein is reproduced under the provision of Section 200(1)(b) of the Copyright Amendment Act 1980 ENV2103 Hydraulics 1 Assignment 1, 2017 2 Question 1 30 marks In a proposed water supply system, two large reservoirs will be connected with a pipeline 52.7 km long and with an elevation difference of 142 metres between the full water levels of the reservoirs. The pipe will be required to convey a minimum discharge of 430 L/s. The proposed pipe material is cast iron. There will be a range of fittings in the pipeline including five 90° short radius bends, four swing check valves fully open, and two 45° elbows. Pipeline entrance and exit types with the walls of the reservoirs will be flush. Determine the required pipeline diameter to convey the design discharge between the two reservoirs using available pipe internal diameters in 25 mm increments from 25 mm to 250 mm, and 50 mm increments for sizes greater than 250 mm. After selecting your pipe diameter, calculate the actual discharge that will occur. Use the Moody diagram and the Darcy-Weisbach equation to complete this design, and submit a clearly marked copy of the Moody diagram along with your submission. (Attempt PEQ 5.6, page 154 of the Study Book before attempting the assignment question.) ENV2103 Hydraulics 1 Assignment 1, 2017 3 Question 2 30 marks Three water mains take three separate routes from a common off-take on a major water trunk line (location A) through to a single connection point for a new network of submains (location B) as shown in Figure 1. Details of the pipelines are provided in Table 1. Table 1: Details of the three pipelines in the parallel system for Question 2 Pipe No. Length (m) Material Diameter (mm) ΣK 1 1720 Concrete pipe 450 17 2 1960 Concrete pipe 300 9 3 2500 Concrete pipe 525 19 For a discharge of (630+z) l/s, where z is the last 2 digits of your student number, determine the head loss between the common off-take and the single connection point using the Moody diagram and the Darcy-Weisbach equation and determine the discharges in each of the pipes. Include a clearly marked Moody diagram for each pipe in your solution, showing Re and k/D for each f, as used in your calculations. Ensure you complete at least two iterations in your solution. Your final continuity error should be less than 1%. Figure 1: (Not to scale) ENV2103 Hydraulics 1 Assignment 1, 2017 4 Question 3 50 marks Part A (30 marks) Two large municipal reservoirs are connected by 2 pipes in series that convey water under gravity flow between the reservoirs. The upstream pipe is connected to the reservoir with a flush fitting, and contains a half open gate valve, four 90° bends and two close return bends. This upstream pipe is asphalted cast iron and is 1450 metres long and 350 millimetres in diameter. It joins the downstream pipe with a sudden change in diameter. The downstream pipe is 450 millimetres diameter and is a concrete lined ductile iron (k = 0.3 millimetres) with a length of 3250 metres. The downstream pipe connects to the lower reservoir with a flush fitting, and contains a fully open gate valve, eight 90° bends and a swing check valve that is fully open. Determine the discharge when the elevation difference between the water levels in the reservoirs is (60 + x) m, where x is equal to the last digit of your student number. Include a clearly marked Moody diagram for each pipe, showing Re and k/D for each f as used in your calculations of friction headloss with the Darcy-Weisbach equation. Part B (20 marks) For the series pipelines, plot the energy grade line (EL) and the hydraulic grade line (HGL). To keep your analysis simple, assume that the fittings contained in each pipe are positioned at a distance of 400 metres from the start of their respective pipe. If you feel that it is necessary to make any assumptions to develop your solution to this problem, clearly state them with any working in your solution. Include a tabulation of the EL and HGL values at key locations along the pipeline system. Your plots may be either hand drawn or computer generated. (PEQ 5.13 provides an example of how to calculate the energy line and hydraulic grade line for a pipeline system.) ENV2103 Hydraulics 1 Assignment 1, 2017 5 Question 4 40 marks A Franklin Electric 250x250-400 centrifugal pump lifts water from a river to a reservoir (pump curve attached). The static lift from the river to the pump is 3 metres and from the pump to the reservoir is 50 metres. The pump has an impeller diameter of 410mm and operates at a speed of 1480 rpm. The details of the suction and discharge pipes are included in Table 2. Table 2: Details of the pipeline for Question 4 Pipe Length (m) Material Diameter (mm) ΣK Suction 15 Cast iron 350 3.44 Discharge 235 Cast iron 350 2.7 Note: The sum of the minor losses, ΣK, include the foot valve in the river and the entrance to the reservoir. Plot the system resistance curve for increments of 50 L/s discharge on your copy of the pump curve. Use the Moody diagram and the Darcy-Weisbach equation to determine friction headloss. Ensure you provide a marked copy of a Moody diagram indicating your selections for f. Determine: a) the operating point for this pump. Clearly state the pump head, discharge, and efficiency at the operating point. b) the input power required at the pump shaft. c) the potential for cavitation at the operating point if the local atmospheric head is 1005 hPa.