SPRINKLE Hydraulic Flow Calculator

Hydraulic Flow Calculator for Fire Sprinkler Systems.

The NFPA (National Fire Protection Association) requires hydraulic calculations to be performed for most sprinkler systems, including NFPA 13R residential fire sprinkler systems. This website is for the 'sprinkle' project, an open, public effort to create a free hydraulic calculator that would be usable for designing such systems.

Currently, the code 'mostly' works, and is usable only by programmers and technically experienced computer users. The code is written in C, and uses a text-file interface. A graphical interface (e.g. gnome) is envisioned. The equation solver functions; there are few other features. This is Free Software, distributed under the FSF GNU GPL license.

Features

Currently, the level of function is pretty basic:

A hydraulic calculator that can deal with systems that have loops in them, as well as trees. Residential NFPA 13D/13R systems are likely to have loops in them, so this is an important feature. It also makes the solver algorithm considerably more complex than it might be otherwise.

The calculator (equation solver) currently seems to function correctly, in that it seems to find plausible solutions. It has *not* been well-tested or independently verified. It could be producing pure garbage, for all I know. I haven't verified any solutions by hand, with a calculator or anything like that.

A simple ASCII file format for entering the sprinkler network topology.

A first cut at handling pipe schedules. Currently, only Victaulic CPVC has been entered.

Uses Hazen-Williams, although it should be easy to add other pipe-flow pressure-loss formulas.

The Solver

The solver took a lot of work to get right. Turns out that solving the (non-linear) flow equations on a pipe network is much harder than one might naively think. Every naive/simple-minded algorithm I could think of would converge only on trivial networks and fail on anything more complex. I tried dozens (literally) without success. Thus, the final solver has a *lot* of research and technology going into it. The solver uses a variety of algorithms to find a solution; read the notes in solver.c to understand how it works.

What's Missing

Lots, I suppose.

Automatically find most demanding sprinkler.
A graphical interface.
Write up documentation
A way of entering pipe schedules more easily
Schedules for tees, elbows, couplings, checkvalves, etc.
Pipe schedules for steel, copper, other pipe types.
Add support for metric systems
Add support for Fair, Whipple & Hsaio
Add support for Darcy-Weisbach

How to Use

This system is currently usable only if you have programming skills and some time to tinker. The system compiles & runs easily on GNU/Linux and probably works on MS Windows.

Download a tarball from the SourceForge Project Site
tar -zxvf sprinkle.tar.gz
Make sure that you have glib-1.2 installed. glib is a collection of C utility functions for handling linked lists, hash tables, and the like.
cd src; make
cat example.fire; ./hydro example.fire

The binary is called hydro. There are six example files, example.fire, example2.fire, etc. The first one shows a system with a loop, and explains the file format a bit. The second shows a simple tree, the third a big tree.

History

Created by Linas Vepstas <linas@linas.org> May 2002 (to validate the system in his house).