From Pipeflow Software web site:

A wide range of hydraulic engineering problems can be solved with Net-Pipe steady-state simulation and unsteady-state simulation: Water-hammer studies for hydroelectric power plants, analyses of surge pressure alleviation for oil pipelines, layout studies for pipe installations, or capacity calculations for water distribution networks, to name a few. Net-Pipe is designed for the hydraulic engineer and for the technical specialist with a background in fluid mechanics.

You can use Microsoft Visio to drag-and-drop the pipe network elements from a customized stencil containing the Net-Pipe hydraulic elements:

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Analysis of Flow in Liquid Pipe Networks:

• One-dimensional steady-state and unsteady-state flow model for liquid pipe networks
• Virtual unlimited number of pipeline and pipe network topologies
• Transient analysis based on method of characteristics
• Over 20 types of time-dependent behavior selectable for valves, pumps, vessels etc.
• Other user defined hydraulic functionality insertable at any point into the network
• Recalculation of friction coefficients in every pipe during steady-state and unsteady-state simulation

Net-Pipe Version 3 Special Features:

• Graphic network layout editor based on standard MS-Windows products
• Display of geodetic height and max. allowable pipe pressure profile
• Simultaneous view of pressure wave and flow propagation
• Pre-selected pump parameters to be imported via standard spread sheet tables
• Simulation recorder for the export of simulation data

For more information see Pipflow Software web site.