Calling all engineering geniuses....
Registered User
Joined: Apr 2010
Posts: 3,848
Likes: 0
From: Southampton/Reading
Looks ok, but you are assuming that PV=C? Compression is an adiabatic process so you would have to factor in the gas co-efficient.
To do it properly is far too complicated for this time of night!
To do it properly is far too complicated for this time of night!
Registered User
Joined: May 2006
Posts: 12,330
Likes: 0
From: Frustration
Originally Posted by gbduo,Dec 6 2010, 11:28 PM
Looks ok, but you are assuming that PV=C? Compression is an adiabatic process so you would have to factor in the gas co-efficient.
To do it properly is far too complicated for this time of night!
To do it properly is far too complicated for this time of night!
Joined: Oct 2006
Posts: 11,445
Likes: 7
From: Plymouth
Ginge is on the money 
A 2 liter engine converted to cubic inches is 122CI
122CI / 1728 (cubic inches in a cubic foot) = .0706 cubic feet
9000 rpm / 2 crank revolutions to fire all four pots (4pot 4cyl) = 4500 induction strokes per min.
4500 spm x .0706 cubic feet = 317.7 CFM.
Assuming 90% volumetric efficiency:
317.7 CFM x .90 = 285.93 CFM
CFM - Cubic feet per minute, being the normal measure of airflow in the car world
So GaryB: "My question is, at 9k rpm, what volume of air is sucked in by the S2k engine per minute."
I say 286 cfm
AS DID DEMBO!
And:
The Blue Bunny ice cream plant facility in Le Mars includes the largest free-standing freezer in the world, which is 12-stories high
(I Googled that)
Steve
A 2 liter engine converted to cubic inches is 122CI
122CI / 1728 (cubic inches in a cubic foot) = .0706 cubic feet
9000 rpm / 2 crank revolutions to fire all four pots (4pot 4cyl) = 4500 induction strokes per min.
4500 spm x .0706 cubic feet = 317.7 CFM.
Assuming 90% volumetric efficiency:
317.7 CFM x .90 = 285.93 CFM
CFM - Cubic feet per minute, being the normal measure of airflow in the car world
So GaryB: "My question is, at 9k rpm, what volume of air is sucked in by the S2k engine per minute."
I say 286 cfm
AS DID DEMBO!
And:
The Blue Bunny ice cream plant facility in Le Mars includes the largest free-standing freezer in the world, which is 12-stories high
(I Googled that)
Steve
Registered User
Joined: Apr 2010
Posts: 3,848
Likes: 0
From: Southampton/Reading
Originally Posted by Ultra_Nexus,Dec 6 2010, 02:33 PM
VE is the factor used to encapsulate that discrepancy, in a rough calc such as this.
Graham
Registered User
Joined: Jun 2006
Posts: 3,423
Likes: 0
From: Reading, UK
Assuming at 9000rpm you are making 243hp = 182kW
So in 1 minute you create 10920kJ of power, assuming 25% efficiency thats 43,680kJ of fuel energy.
With 46MJ/kg thats 0.93kg of fuel.
Can work out the rest from the Air fuel ratio (using mass) to get the equivilant air by Volume.
So in 1 minute you create 10920kJ of power, assuming 25% efficiency thats 43,680kJ of fuel energy.
With 46MJ/kg thats 0.93kg of fuel.
Can work out the rest from the Air fuel ratio (using mass) to get the equivilant air by Volume.
Joined: May 2010
Posts: 8,076
Likes: 86
From: Costa del Cornwall
I think it's time to wrap up this thread, as we all have to dress up as Klingons and go to a trekkie convention.
As Nick stated the answer is piss easy, 1 liter per rev, unless you are in the USA then it's 1.1, discuss and say why.
As Nick stated the answer is piss easy, 1 liter per rev, unless you are in the USA then it's 1.1, discuss and say why.
