Italiano
An old Sicilian proverb states:
“You need some wind in church, not so much to blow out the candles though!”.
Ah, the old wisdom in saying that everything requires the right measure…
In any case, the proverb is particularly apt to describe the velocity of make-up air, as reintroduced into the room from a compensating air-extraction system!
A team of Malaysian researchers talks about it in a paper published by the prestigious EDP Sciences, entitled “Optimizing of Make-Up Air Performance for Commercial Kitchen Ventilation Improvement” (You can read it HERE).
The article presents the data collected in a simulation in which 4 different air reintroduction speeds into the environment were tested: 0 m/s, 0.14 m/s, 0.28 m/s, 0.42 m/s.
They chose to simulate the test on a medium-sized kitchen (10m x 8m x 3m).
The “zero” velocity, easy to imagine, does not bring those advantages for which the compensation system is chosen: creating a negative pressure in the room, and decreasing the temperature in the work environment.
The velocity at 0.14 m/s is too “soft”, and does not bring any substantial advantage.
The maximum velocity, at 0.42 m/s, is too much. It makes the kitchen temperature very comfortable, but it is so strong that it considerably complicates the brigade’s work.
So the contest is won by the median velocity: of 0,28 m/s!
It reduces the temperature but does not complicate the chef’s life.
He doesn’t blow out the candles, so to speak!
