Course Project
Students will work in groups of three to prepare a final report as well as a PowerPoint presentation. The student from each group to present the presentation will be drawn at random at the beginning of the class period. A disk is to be turned in along with a printout and is due the same day. Presentations will be timed and are to last 8 minutes not including questions.
The theme of this year's projects is water is a precious commodity?
Design of Water Distribution systems
Background:
A water distribution system transport water from sources of supply to various locations where there is a varying water demand for residential, commercial, and industrial uses. Typically, a distribution system consists of large number of interconnection pipes through which the flow to a given outlet may come from several loops (circuits).In general the problem is complicated and requires trial solutions until all conditions for the flow (i.e., mass continuity at each junction and conservation of energy around each closed loop) are satisfied. A computerized water distribution network analysis system will greatly aid engineers in analyzing and designing a water distribution network which is often the major investment of a municipal water works.
EPANET is a program for analyzing the hydraulic and water quality behavior of pressurized pipe networks. It was developed by the U.S. Environmental Protection Agency's National Risk Management Research Laboratory.
EPANET was developed by the Water Supply and Water Resources Division (formerly the Drinking Water Research Division) of the U.S. Environmental Protection Agency's National Risk Management Research Laboratory. It is public domain software that may be freely copied and distributed.
Description of EPANET
EPANET is a Windows 95/98/NT program that performs extended period simulation of hydraulic and water-quality behavior within pressurized pipe networks. A network can consist of pipes, nodes (pipe junctions), pumps, valves and storage tanks or reservoirs. EPANET tracks the flow of water in each pipe, the pressure at each node, the height of water in each tank, and the concentration of a chemical species throughout the network during a simulation period comprised of multiple time steps. In addition to chemical species, water age and source tracing can also be simulated.
Flow resistance formulae:
Colebrook-White equation, William-Hazen equation, Darcy-Weisbach equation.
Main constraints:
- Continuity of flow at nodes
- Maintaining minimum and maximum pressure
- Conservation of energy in the loop (i.e., head loss)
Flow state:
Steady state is assumed for design. However different operational states may be satisfied. You may use the necessary equipment such as booster pumps, regulating & controlling and pressure reducing valves as needed.
Facts:
Network of distribution mains is the most expensive item of equipment.
Selection of pipe materials:
The selection of pipe materials is based on some factors (i.e., roughness coefficient, maximum allowable pipe pressure, and cost items of the objective functions).
Demand:
One or more demand rates may be specified for design (i.e., peak demand, fire fitting demand, low consumption periods demand). The demand must estimated for : Residential area, Industrial area, Hospitals (Per Bed), Schools, Hotels, Stores, Offices, and Small Businesses, Shopping Centers, Mosques, etc.
Assignment:
Design a pipe network in the selected area using Hardy-Cross method and all principles and theories you have learned in this course. Find flow rates and direction of flow in each pipe and the pressure at each node. We should design for the most efficient distribution system which can be achieved by having accurate prediction of flows and pressures in the various pipe components.
Procedure (Design steps):
1- Select a map to scale for an area having about 200 lots (house connection) and an area of 0.25 –0.5 km2.
2- Obtain a topographic map for the area.
3- Identify the type of buildings (i.e. residence, commercial buildings public facilities, etc.)
4- Get the approval of the instructor before starting the project.
5- Trace the map on a different sheet.
6- Lay out all pipelines along the roads and streets. Pipe mains interconnections should not exceed 600m.
7- Identify your loops. (Keeping in mind that: water from the main distribution grid shall enter individual loop from at least two points). Dead ends should be avoided as far as possible.
8- Number your loops and nodes and pipelines.
9- Identify all feed and drawoff lines.
10- Identify all controlling valves to the area.
11- Piping material shall be Polyvinyl Chloride (PVC), Ductile Iron (DI), Fiberglass (GRP), Asbestos (not recommended due to health problems) for diameter up to 710 mm.
12- Tabulate your data of pipe length, diameter, roughness and type of pipe material.
13- Tabulate your data of node numbers, elevations, pressure elevation heads, and demands.
14- Identify the fire hydrant locations and demand.
15- Show your calculation of houses and fire hydrant demands and give the references used.
16- Go to the library and choose at least three references of design books and manuals.
17- Attach a copy of the materials used from these references to your report in the appendix section.
18- Input your data to EPANET 2.0 program and run the program for the following demand scenarios:
a) Peak daily demand (with peaking factor of 3.00).
b) Maximum hourly demand (with peaking factor of 2.80).
c) Maximum daily demand plus fire flow (with peaking factor of 2.50).
19-Maintain the following constraints:
a) Velocity should be in the range from 0.6 m/s – 1.2 m/s. Maximum velocity in the system should not exceed 2.00 m/s.
b) Presser in pipes should be from 1 bar to 3 bars.
c) Feed line pressure from 2 bars to 7 bars.
d) Frictional losses between 1 to 10 /1000m of main.
20- Write your reports to include the following:
a) Cover Page
b) Table of contents
c) Introduction
d) Problem description
e) Objectives
f) Theoretical background
g) Sample of calculation
h) Tabulated input data
i) Program results
j) Listing of all outputs
k) Discussion of results
l) Conclusion
m) References
n) Appendix
o) A diskette including all inputs/outputs
21- The report of this project must be submitted after 3 week from the date of assignment.
22-Only three to five students are allowed in each group.
Note: The following link presents useful materials of design criteria and specifications for water mains prepared for City of Tullahoma, Tennessee, USA:
http://www.tub.net/pressuresewerspecs.htm
Please read and any related ideas.
Note: Please take the related handout from the printing office in Building D.
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