This document is intended to assist engineers in the use of the Pipe Liquid-Flow computer program. The computer-based program utilizes the Microsoft’s Excel spreadsheet program and contains embedded macros that quickly solve basic liquid-flow hydraulic problems with a minimum of set-up time. This user’s Guide will explain the required input parameters, output parameters and the methods used to solve basic liquid-flow hydraulic problems. It will also describe the program limitations and error checking capabilities. Example problems are given in both USC and SI units and are intended to help users understand how the computer program can be used to find solutions to everyday engineering problems.
This computer program was prepared with two purposes in mind. The first was to help engineers who are new to the field of fluid hydraulics learn basic fundamental topics without having to solve problems using tedious and repetitive hand calculations. Nothing hinders the learning experience more than consuming time writing down equations, gathering data and organizing the solution only to get the wrong answer because of a simple arithmetic error. Even more frustrating is the correct answer may not be known until the procedure is checked or verified by others. The other purpose of this computer program is to assist engineers with simple solutions to real-world liquid flow problems commonly found in everyday job assignments. While this computer program may not be capable of solving all liquid flow problems, it can handle the vast majority. It is especially well suited to those problems that require minimal input data or require repetitive calculations to solve.
The Pipe Liquid-Flow computer program is easy to use and provides quick solutions to common engineering fluid flow hydraulic problems. Users of Microsoft’s Excel program will find it easy to install. Those with a basic knowledge of hydraulics will quickly adapt to the input data requirements and find how easy it is to modify the data for alternate solutions. Users will also find the results easy to understand. The computer program utilizes two Excel worksheets to display input parameters, output parameters, command buttons and warning messages. The two worksheets are Menu and Liquid-Flow, which are described below.
The Menu lists notes that briefly describe the program’s basis of flow and pressure calculations, input and output parameters and the equations used to determine the results. The worksheet is also used to select the units of measure. There are two options for units of measure:
1. United States Customary (USC) 2. Systeme Internationale (SI).
The user can select the desired units by pressing one of the follow command buttons.
For example:
The Menu worksheet will display either USC or SI as the selected units.
See the attachments section for an illustration of the Menu worksheet.SI Gas Flow Worksheet USC Gas Flow Worksheet
The Liquid-Flow worksheet is used to input required parameters and present calculated output parameters. Input parameters are designated by yellow boxes and are followed by the units of measure. Users will need to enter required values in each of these boxes. See the attachments section for an illustration of the Liquid-Flow worksheet.
SI Liquid Flow Worksheet USC Liquid Flow Worksheet
Example of designated input parameters:
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The following is a list of required input parameters:
| Parameter | Abbreviation | USC Units | SI Units | |
| Flow Rate | gallons/nub - gpm | |||
| Pipe Inside Diameter | inch | mm | ||
| Viscosity | |
Centipoise - Cp | Centipoise - Cp | |
| Specific Gravity | - | - | ||
| Pipe Length | L | feet | meters | |
| Absolute Roughness | feet | meters | ||
| Pipe Inlet Pressure | kilo-Pascals absolute - kPaa | |||
| Pipe Inlet Elevation | feet of liquid | meters | ||
| Pipe Outlet Elevation | feet of liquid | meters |
The user should enter input values applicable to the current calculation for each of the parameters listed above. If the value displayed in the yellow box is correct for the current application, no addition change is needed. Once the input value is entered into each box, press the Calculate command button. For example:
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The computer program will automatically begin calculation of the output parameters and display results on the Liquid-Flow worksheet.
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