Calling all engineering geniuses....
12-06-2010, 11:16 AM
#11
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........ roughly 720,000 litres, 720cubic metres....... roughly a freezer a 3rd the size of an olympic swimming pool. Too many variables for my liking so Im sticking with my roughly calc 
12-06-2010, 11:23 AM
#12
1 litre per revolution; only one is on suck for the first half, three is on suck for the 2nd half.
Bearing in mind it's quite depressed in there, due to the small curtain area of the valves etc. So it's not 9,000 litres per minute.
Bearing in mind it's quite depressed in there, due to the small curtain area of the valves etc. So it's not 9,000 litres per minute.
12-06-2010, 11:25 AM
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Originally Posted by oxhouser,Dec 6 2010, 12:06 PM
its swept volume not cc so slightly less than 2ltr per rpm and thats not taking into account losses in the intake or gains through scavange and ram
edit do they count the cylinder head when stating the engine capacity or do they use swept volume? never though about this before
edit do they count the cylinder head when stating the engine capacity or do they use swept volume? never though about this before
12-06-2010, 11:25 AM
#14
1 litre per rev * 9000 = 9000 litres per minute. 
Or if 10% of it is fuel then I guess you could say 8100 litres per minute.
I don't know where you get 720,000 litres.
Or if 10% of it is fuel then I guess you could say 8100 litres per minute.I don't know where you get 720,000 litres.
12-06-2010, 11:36 AM
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Originally Posted by Nick Graves,Dec 6 2010, 12:23 PM
1 litre per revolution; only one is on suck for the first half, three is on suck for the 2nd half.
Bearing in mind it's quite depressed in there, due to the small curtain area of the valves etc. So it's not 9,000 litres per minute.
Bearing in mind it's quite depressed in there, due to the small curtain area of the valves etc. So it's not 9,000 litres per minute.
assume cyl 1 and 4 at TDC and 2& 3 at mid way
180 degrees makes cyl 1 fill and 4 empty
cyl 2 takes half a cylinder and 3 empties half
so thats 500 cc + 250 + 250 = 1 ltre for 180 rpm the next 180 degree does the same volume but its the 4 and 3 filling and 1 & 2 emptying
not used firing order just went in order
am i right?
12-06-2010, 11:42 AM
#18
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Originally Posted by Dembo,Dec 6 2010, 09:25 PM
1 litre per rev * 9000 = 9000 litres per minute. Or if 10% of it is fuel then I guess you could say 8100 litres per minute.
I don't know where you get 720,000 litres.
Or if 10% of it is fuel then I guess you could say 8100 litres per minute.I don't know where you get 720,000 litres.
12-06-2010, 11:50 AM
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Right I got an answer, but I am not 100% sure it is right, in fact far from it because I have never calculated this before!
So I started off with petrol, which is by mass:-
86% Carbon
12% Hydrogen
2% Oxygen
These were somewhat made up, but they seemed realistic enough, they gave a HCV of 45.6kJ/Kg of fuel, which is fairly close to the standard for Petrol which is 47kJ/Kg. So notice first assumption!
Then did a wet gas analysis:-
O2 required to burn the fuel is 3.279Kg per Kg fuel
CO2 produced is 3.153kg per kg fuel
H2O produced is 1.08kg per kg fuel
This then gave a stoichiometric of 14.257:1. Bugger.
So I am well out I think, but by working out the volume per cylinder and the amount of the stoichiometric you could fit in the cylinder per revolution, I got 429.9cc + fuel.
If the cylinder is on its induction stroke every other revolution, this gives 429.9 x 75 which is 32,242cc. In sensible figures that is 32.245 tonnes of air required at 75rev/s. Quite frankly, I think that is ridiculous. But I thought I would share my failure with you all.
Good luck to the next person!
Graham
a sh1t engineer.
So I started off with petrol, which is by mass:-
86% Carbon
12% Hydrogen
2% Oxygen
These were somewhat made up, but they seemed realistic enough, they gave a HCV of 45.6kJ/Kg of fuel, which is fairly close to the standard for Petrol which is 47kJ/Kg. So notice first assumption!
Then did a wet gas analysis:-
O2 required to burn the fuel is 3.279Kg per Kg fuel
CO2 produced is 3.153kg per kg fuel
H2O produced is 1.08kg per kg fuel
This then gave a stoichiometric of 14.257:1. Bugger.
So I am well out I think, but by working out the volume per cylinder and the amount of the stoichiometric you could fit in the cylinder per revolution, I got 429.9cc + fuel.
If the cylinder is on its induction stroke every other revolution, this gives 429.9 x 75 which is 32,242cc. In sensible figures that is 32.245 tonnes of air required at 75rev/s. Quite frankly, I think that is ridiculous. But I thought I would share my failure with you all.
Good luck to the next person!
Graham
a sh1t engineer.
12-06-2010, 11:54 AM
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I have just noticed the 32.45 tonnes doesn't even line up with my stoichiometric, damn I really am bad tonight! If anyone is that interested, I could ask my thermo teacher to give me a hand tomorrow and I can come back with a definite answer?