Engine Room Ventilation.

Momac

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27m3 per minute might seem like a lot but I am not sure it is in practice.
eg That's about a dozen air changes per minute for a 2m3 engine bay.

A 5 inch 4 amp 12V bilge blower fan could move 6m3 per minute . But why should the fan be required when the engine is itself a good air pump?
 

PaulRainbow

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Does your estimate allow for only filling the cylinders on every other stroke - assuming 4 stroke?
It doesn't John.

"estimating the engine will need 6 liters to fill the cylinders, 3000 times per minute, you get the result 18.000 litres"

Should only be 9,000 litres per minute.

EDIT, that's for non turbo diesel
 
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penberth3

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It doesn't John.

"estimating the engine will need 6 liters to fill the cylinders, 3000 times per minute, you get the result 18.000 litres"

Should only be 9,000 litres per minute.

EDIT, that's for non turbo diesel

Thanks Paul, my mental arithmetic gave me 9000 litres/min, but I wasn't sure!

And that is per minute, not per litre of diesel which was quoted in Post #15.
 

ss2016

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Looked at a different way. I think the numbers following are correct, and if so you are underestimating. Happy to stand corrected.
My understanding is to burn a litre of fuel you need in practice about 9000 lit of air.
At WOT your engine burns (??????) 1.4lit/min, so that is 12600lit/min.
You have 2 engines so about 25000lit./min.

And a different point you do not want to introduce a second resistance to the incoming air, and at that stage its less dense. So if 2 *575hp is what you want its perhaps time to adjust the furniture!
 
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