AACALC8 is a very simple, but useful FREE Windows application that runs on 10" Netbooks, all laptops and the monitor on your desk and is in 5 sections :-

Click here to download AACALC8 [520 kB] directly.

The first screen above determines the minimum number of sprinkler heads of a given coverage in a room or building - you just move the 3 'sliders' to suit and the best arrangement is highlighted with other valid arrangements shown. Note how the spacings between heads has been rounded to the nearest 5 mm that all expert designers apply.

The second page is in two parts - the top section allows you to vary a sprinkler head "K" factor, the flow, pressure, density, area and specific gravity to see the remaining 'sliders' adjust accordingly. As you would expect, all the 6 controls affect one or more of the other values following the standard formula. The "K" factor can be all the standard ones - 57, 80 and 115 as well as 112, 143, 160, 200, 242, 322 up to 362 for ESFR heads. The bottom section takes this head / nozzle flow / pressure down a end-fed or centre-fed range of 6 pipes of a set slope and pipe type (M, MW, DIN or S40) but you can vary the maximum velocity as required and see how the density / pressure values change - very useful for selecting the pipe sizes in a subsequent full hydraulic calculation.

The third page is again in two sections - the top part allows you to adjust 'sliders' for pipe size,
length, "C" factor and flow to determine the pressure drop (using the Hazen-Williams formula) and the
velocity. I have added the *reverse* so you can adjust the pressure drop slider to recalculate the
flow rate keeping the diameter and length constant and adjusting the velocity will recalculate the
pipe size keeping the flow rate the same. The lower part just allows you to type in the same information
to a higher accuracy or range and do the same pressure drop / velocity calculation, so you can do
two comparisons at the same time or check any hydraulic program printouts.

9th October 2013 - I have added the ability to enter or convert the 4 questions and 2 answer boxes into different units of measurement if these are more familiar to you.

17th April 2013 - fourth page is the same as the GRAPH part of FREESHP and allows you to select the pipe type (in A-Z order), the Hazen Williams "C" factor and the maximum flow rate (from 100 to 50000 L/min) whereby the corresponding pressure drop is shown, with the velocity in green, for each of the applicable pipe sizes.

5th June 2014 - I have added another useful calculation - that of the reduced pipe size to balance the most favourable pressure in a sprinkler system with the most remotest design area. Simply select the size of the distribution pipe, its type, flow rate and the pressure to absorb by moving the 4 'sliders' to the appropriate values to view the lengths, velocities etc of the possible reduced pipe sizes.

You will note that I have kept to the new Microsoft "everything is white now" concept in Windows 8 (but have added a bit of colour (sic) in my own inimitable way in larger font sizes but can easily change it to 10 point black and grey text if you prefer). I have also left room for any other little calculation routines you may wish to suggest by Email.

If you wish to question the originality of AACALC8 then
just look up Page 14 of the February 1993 issue of the (now defunct) *Fire Surveyor* magazine where there was
a very interesting article about "Sprinkler Calculation Computer Programs" by somebody called Alan Ashfield who
offered the same 3 algorithms (+ one about orifice plates no longer applicable) to people who sent me a 3.5" floppy
disk. I had about 50 requests - does anybody still have (or use) that DOS disk?

Click here to download AACALC8 [520 kB] directly.

Copyright 2015 by Alan Ashfield