Hydraulic Calculation Examples

FHC hydraulic calculation software is able to calculate almost any type of water-based fire protection system from the conventional tree pipe configuration to the more complicated roof and rack gridded systems.  FHC is not just limited to sprinkler systems but also has many users worldwide are using our software to aid in the design of high and low-pressure water mist systems using conventional pump sets,  pressurised cylinders and constant pressure pumps.

You will find below several fire sprinkler hydraulic calculation example which demonstrates the versatility of our software and its ability to calculate any type of water-based fire protection system.  If you do not see the type of project that you are working on, we probably have seen it before so if you require further information, please don't hesitate to contact us. 

ESFR fire sprinkler system with addition rack protection

ESFR fire sprinkler installation installed into major car manufacturer’s parts facilities and is somewhat bespoke in its design. The roof level sprinklers are ESFR 25mm with a K-factor of 360 and a minimum head pressure of 3.5 bars. In addition, the rack storage below is protected with 20mm sprinkler with a K-factor of 115 and a minimum head pressure of 1.0 bar. The final water demand requirements for the system was 9849 L/min @ 9.0 bar and the design aided by FHC achieved 98% design efficiency.

This FHC hydraulic model consisted of 810 pipes, 154 loops and 26 heads. It was calculated on a Pentium VI computer in under 0.1 seconds.

Example of a multiple loop hydraulic calculation in FHC

An FHC hydraulic calculation that demonstrates its capabilities and shows a perfect balance of flows through the pipe network consisting of 106 pipes and 15 loops in its calculation. The system has loops within the loop, four in all. The FHC software easily produced the hydraulic calculations for this system showing its versatility.

Fire sprinkler system in a tree pipe work configuration

Fire sprinkler systems often use tree pipe work configuration in the system design and although this configuration is not as hydraulically efficient as a loop or grid system it still has its uses.

For complex buildings such as schools, residential care homes and systems which require a dry fire sprinkler installation to be installed, a tree system can be the way to go. The pipe work in tree work configurations can be sized in a conventional way by using pre sized pipe tables for the number of sprinkler heads or by fully calculating the hydraulics by hand without much difficulty, but even for small systems, they are still very time consuming and prone to human error.

By using FHC you have all the advantages of full hydraulic calculations in helping you reduce your pipe sizes and/or the water demand. Furthermore, the calculations will not have the human error factor and will only take a fraction of a seconded to calculate allowing you the designer more time to optimises the system and reduce costs.

Deluge fire protection system

Deluge installation of any type can be modelled with the FHC program. In this example, medium velocity sprayers are protecting a vertical cylinder. Within the FHC hydraulic model, we specified an area for each nozzle and a minimum design density of 10 mm/min.

NFPA 750 hydraulic calculation for a water mist system

A calculation for a high-pressure water mist fire protection system designed to NFPA 750. For high-pressure systems, you should use the Darcy-Weisbach pressure loss equation which can take into account both the fluids absolute viscosity (centipoises) and the density of the fluid.

The water supply can be from a pressurised cylinder, constant pressure pump or any other type of water supply. Custom nozzle and pipe data files can be used for the hydraulic modelling of water mist systems.  Canute can provide customised pipe data files and nozzle data files based on any water mist manufacturer data.

Hydraulic calculation for EN 12854 High Hazard roof system

FHC is being used to hydraulically module an EN 12845 high hazard fire sprinkler system. The system is for roof protection only and is designed to provide 10mm/min density over 260m2.


The model has 412 pipes, 30 loops and 31 operation heads (K80 min pressure of 0.5 Bar), FHC calculated this systems in 0.06 seconds.