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The application of Appropriate Technology

Gravity Flow Spreadsheets & Calculations

Articles and spreedsheets to help you with the calculations necessary to design gravity flow water systems.

  • Articles:

    Fluid Mechanics For Gravity – Flow Water Systems and Pumps

    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.

    Natural Flow Calculator Spreadsheet

    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.

    Head Loss Calculator Spreadsheet

    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 […]

    Friction Loss Tables

    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.