19 June 2026
Why we now model every impulse scheme before we quote it
Two schemes in five years had a dead zone that nobody predicted from a plan view. Modelling costs us about a day and it has stopped both arguments happening again.
Impulse ventilation is sold on a plan view: fans as arrows, a route to the extract, and a note about coverage. That works right up until the structure gets in the way — a downstand beam, a core wall, a ramp that turns a corner — and then a corner of the level does not clear and the CO monitor sitting in it drives the plant to full speed permanently.
It happened to us twice, in 2021 and 2023. Both were fixable, both cost us money and cost the contractor programme, and in both cases the plan view looked completely reasonable. What they had in common was that neither had been modelled.
Since January 2025 we build a CFD model of every impulse scheme before quoting, using the actual structural model rather than an idealised box. It costs us roughly a day of engineering time per scheme. We do not charge for it separately, and we issue the velocity plots with the quotation so you can see the corners for yourself rather than trust the arrows.
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5 May 2026
Holding spares for fans we sold in 1998
Bearings, belts, impellers and motor frames for every fan built in the last twenty-eight years. The commercial argument for it is worse than you would think, and we are keeping it.
Next step
Send us the duty and we will send back a curve
Volume, static pressure, air temperature and what is in it. If you only have two of those, ring us and we will work out the rest.