Equations..

[orlin steven jared]

>         PV=nRTe
>            P = pressure [assuming intake from MAP sensor] in KPA
>            V = Displacement of Cylinder                   in Liters
>            N = moles of atmosphere                        in Moles
>            R = Universal gas constant : 8.31L/Kpa         W/ KPA & Liters
>            T = Absolute temp ¡K of intake air [temp sensors job]
>            
>            Could you help me nail down the real units on these things? I'm a 
> second year chemistry student, and I know this simple Gas law but I don't know 
> the units in this Application!!!

You're a second year chemistry student and you don't have a chem book
with these units written inside the front cover ? %-)

Pressure has dimensions:   force/length squared
Volume has dimensions:     length cubed
n has no dimensions (primary dimensions anyways) the units are moles
T has secondary dimension, temperature (sometimes a primary dimension).

Knowing the above, you can rearrange the equation and get the dimensions
and therefor, units, of the universal gas constant (which I always forget
myself).

I have never seen the ideal gas law used in conjunction with
volumetric efficiency like you state above, however.   That doesn't
mean that it isn't -I just haven't seen it.  Maybe someone else can
elaborate.


There are many ways to calculate volumetric efficiency.   I can
bring in some formulas later.  But typical values for spark ignition
engines run about .5-1   (1 being an all out race engine).


Steve