Exhaust gas volumetric rate
Exhaust gas volumetric rate
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Discussion

greeer

Original Poster:

25 posts

121 months

Wednesday 21st March 2018
quotequote all
Hello!

Does anyone know the approximate maximum exhaust gas volumetric flow rate of a regular diesel engine?
I am talking about a Ford 1.5-2L not any 4.8L monster or something.

Thanks!

bolide

582 posts

278 months

Wednesday 21st March 2018
quotequote all
Cylinder volume x number of firing cycles @ max rpm x volume uplift for combustion / seconds?

I would expect the volume of exhaust gas will exceed the cylinder volume as combustion will generate more volume. But that factor should be Googleable

Nick Froome

AW111

9,674 posts

157 months

Thursday 22nd March 2018
quotequote all
Exhaust gas volume is approx. capacity x revs x VE x expansion.
2l engine @4500 rpm = 75 litres / sec nominal intake air.

Assume VE of 0.95
Exhaust temp of 850 C (at the head) so expansion of (850+273) / (20+273), or around 3.7 (assuming no back pressure)

So my back-of-envelope says around 200-250 litres / sec.

I await Max_Torque or another qualified engineer telling me how wrong I am, and why smile

Edit - I forgot to allow for water vapour (product of combustion), so my numbers are probably bks frown

Edited by AW111 on Thursday 22 March 11:46

greeer

Original Poster:

25 posts

121 months

Thursday 22nd March 2018
quotequote all
AW111 said:
Exhaust gas volume is approx. capacity x revs x VE x expansion.
2l engine @4500 rpm = 75 litres / sec nominal intake air.

Assume VE of 0.95
Exhaust temp of 850 C (at the head) so expansion of (850+273) / (20+273), or around 3.7 (assuming no back pressure)

So my back-of-envelope says around 200-250 litres / sec.

I await Max_Torque or another qualified engineer telling me how wrong I am, and why smile

Edit - I forgot to allow for water vapour (product of combustion), so my numbers are probably bks frown

Edited by AW111 on Thursday 22 March 11:46
This cannot be serious, do you realise how large is 200L per second?

Here it shows that normally it's 2.5m3/min which is 2500L/min which is 42L/second.

http://www.sokken.co.jp/files/products/AirFlowmete...

But again it looks huge. It is from a 4.8L engine. I need for 2.0L maximum, should I assume half of it?

GreenV8S

30,999 posts

308 months

Friday 23rd March 2018
quotequote all
AW111 said:
Exhaust gas volume is approx. capacity x revs x VE x expansion.
2l engine @4500 rpm = 75 litres / sec nominal intake air.
Times half, if it's a four-stroke.

AW111

9,674 posts

157 months

Friday 23rd March 2018
quotequote all
GreenV8S said:
AW111 said:
Exhaust gas volume is approx. capacity x revs x VE x expansion.
2l engine @4500 rpm = 75 litres / sec nominal intake air.
Times half, if it's a four-stroke.
I did that. 4500 rpm is 75 revs / sec, times 1 litre (2 litres / 2)