Fuel Properties
Posted: Thu Jan 30, 2020 6:59 am
I would like some more info about the fuel properties.
It looks like if you really want to be able to change the fuel mixture aim and have a reasonable expectation of hitting the target, you need to get the fuel properties correct. There seems to be quite a variation in density (693 - 786 kg/m^3 ; or .693 - .786 specific gravity) according to this source:
https://vpracingfuels.com/master-fuel-tables/
At least that can be measured easily for the fuel you have.
It also looks like the molar mass of fuel could be calculated from the specific gravity, so why is there a separate property for that?
Finally, it also seems the Stoichiometric Ratio also varies with fuel -- and this is also used in the calculation of Engine Load.
Perhaps we should be changing the Fuel's Stiochiometric Ratio as a first order adjustment when a Fuel Mixture Aim change does not produced the expected step.
I would appreciate any thoughts or insights anyone would wish to share...
It looks like if you really want to be able to change the fuel mixture aim and have a reasonable expectation of hitting the target, you need to get the fuel properties correct. There seems to be quite a variation in density (693 - 786 kg/m^3 ; or .693 - .786 specific gravity) according to this source:
https://vpracingfuels.com/master-fuel-tables/
At least that can be measured easily for the fuel you have.
It also looks like the molar mass of fuel could be calculated from the specific gravity, so why is there a separate property for that?
Finally, it also seems the Stoichiometric Ratio also varies with fuel -- and this is also used in the calculation of Engine Load.
Perhaps we should be changing the Fuel's Stiochiometric Ratio as a first order adjustment when a Fuel Mixture Aim change does not produced the expected step.
I would appreciate any thoughts or insights anyone would wish to share...