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Articles for Keyword "gravity flow"

Construction of a Gravity-fed Water Supply and Treatment System in Developing Countries

Posted on Oct 25, 2011

This paper covers every aspect of the design and construction of a water supply system utilizing potential energy (gravity) for delivery. The typical layout of a gravity-fed water system includes a water source, transmission main, reservoir and distribution system. Every component between the water source and the reservoir is discussed in this paper, which focuses on everything related to the transmission main. This includes pipeline route survey, water resource planning, pipeline design and pipeline construction. Water treatment systems are introduced and discussed briefly. For more information on these vital components of a water supply system, refer to the sources at the end of this paper for further reading. All calculations and measurements were done using the metric system. A large majority of communities that would find this information useful use the metric system. You can read the whole document as a PDF...

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Distribution Network

Posted on Nov 20, 2011

In this system each family got their own tap that is connected to the reservoir tank using a polyethylene pipe network. The exit pipe work at the base of the reservoir. Making the tapstands. Fixing a t-joint into the distribution pipe work. A finished tap...

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EPANET Program Download And Manuals

Posted on Nov 17, 2011

From the links below you can download the EPANET program for free and also download the EPANET manual. Download EPANET 2.0.1.1 (1.5 mb zip file) Download the EPANET Manual (1 mb pdf file) Download EPANET website can be found at ...

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Fluid Mechanics For Gravity – Flow Water Systems and Pumps

Posted on Jun 5, 2011

A text detailing the design of water systems including the design parameters recommended for a successful and long lasting water supply. Issue 2 May 2003.

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Friction Loss Tables

Posted on Oct 25, 2011

Data for frictional losses in plastic pipe Diameter: 13-75mm, Flow rates: 0.06-3.15LPS, Frictional coefficient: C=150 This table is available as a PDF.

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Gravity Flow Water Supply

Posted on Oct 25, 2011

By Santiago Arnalich Castañeda. This book intends to provide you with the tools needed to complete a sucessful gravity flow water project in a short amount of time. You may well already be dealing with a real life project, but without the time to do intensive study to get up to scratch. This book is meant to be: 99% Fat Free – Only what you really need is included. Simple – One of the most common causes of failure is that the complexity and excessive rigour become very intimidating, and things get left half done. Chronological – It more or less follows the logical order in which you’d undertake the project. Practical – With calculation examples. For a generous step by step exercises collection see “How to design a Gravity Flow Water System Through Worked Example“, a book from the same author. Self contained – It is assumed that you are in a remote area with not access to information, so all the essential information is included. Never the less links to other sources of information are provided. You can read the whole of Gravity Flow Water Supply on Google...

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Head Loss Calculator Spreadsheet

Posted on Oct 25, 2011

This spreadsheet allows the user to calculate the frictional head loss (m) for a given flow rate (LPS) and pipe length (m), for a series of different diameter pipes (in). The user can also find the optimum combination of 100m sections of two pipes of different diameters (in) to “burn off” a given frictional head (m). Microsoft Excel...

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Natural Flow Calculator Spreadsheet

Posted on Oct 25, 2011

This spreadsheet allows the user to calculate the natural flow rate (LPS) of any combination of up to 4 pipes of different diameters (in) for given pipe lengths (m) and known head (m). Microsoft Excel Spreadsheet (165KB) *** Note: this spreadsheet contains macros, and you may get a security warning.

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Part 5: Energy in a Perfect System – The Bernoulli Equation

Posted on Jun 5, 2011

Anywhere in a perfect system (i.e. there are no frictional effects), for an incompressible fluid there are three types of energy existing: Pressure Energy. Example: If you blow up the tyre of a car with a pump you are turning your physical energy of working the pump into pressure energy in the tyre. Kinetic Energy. Example: This is the energy contained in a moving fluid. If a wave hits you at the beach, you feel the kinetic energy contained within it. Potential Energy. Example: Gravity is trying to pull water to the lowest point on the earth’s surface. So when water is at a high point it contains energy, which can “potentially” allow it to flow down. At any point in a perfect system the sum of these “bits” of energy in different forms (Pressure, Kinetic and Potential) must equal the sum of these “bits” at any other point in the system. This is because energy cannot be “created” or “destroyed”, it can only change its form. This is what the BERNOULLI EQUATION expresses. Appendix 1. gives the derivation of the Kinetic Energy in terms of a pressure and Appendix 2. gives the derivation of the Potential Energy in terms of a pressure. These different forms of energy are expressed mathematically (as pressures) in the Bernoulli Equation (for a perfect system) shown below: (12) The terms on the left hand side of the Equation are as follows: P1 is the pressure energy at point 1 (expressed as a pressure). [Units are N/m2 or Pa] ρ is the density of the fluid.[Units are Kg/m3] v1 is the velocity of the fluid at point 1. [Units are m/s] g is the acceleration due to earth’s gravity (9.81 m/s/s).[Units are m/s/s] h1 is the height (from a given datum) of the fluid at point 1.[Units are m] The terms are similar on the right hand side of the Equation, but for point 2. The left hand side of the equation represents all the “bits” of energy (expressed as pressures) at a point 1 in a perfect system and the right hand side all the “bits” of energy (expressed as pressures) at another point...

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Reservoir Tank – Mould

Posted on Nov 20, 2011

The reservoir tank is placed at a point near the village that is higher than all the houses that are to be supplied. The tank must be large enough to ensure an uninterrupted supply during the times of day when there is the peak demand. The tank is thus sized according to the size of the population and the flow rate from the spring during the dry season. The tank in this system is a 13 000 litre tank made from reinforced concrete using a pre-fabricated mould. The tank has a vaulted brick roof, a method that is both cheaper and quicker than making a reinforced concrete roof. Preparing the ground for the reservoir tank. Flattening the gravel base. Adding a layer of stones to the base. Pouring the concrete base onto the prepared gravel and stone layers. Finishing the concrete base. Adding re-bar to the base to provide reinforcement. Preparing the rebar for the reservoir tank wall. Constructiong the inside wall of the reservoir tank mould. The completed inside wall of the reservoir tank mould with re-bar around the outside.. Fitting the bottom layer of the mould’s outer wall. Mixing the concrete for the walls. Filling the bottom layer of the mould with concrete. Filling the top layer of the mould with concrete. The Filled Mould. The view inside the mould showing the exit pipe. Removing the outside sections of the mould. The outside of the tank wall once the mould is removed. Plastering the inside walls of the tank. Plastering the outside walls of the...

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