How to Calculate Exhaust Flow Rates Using Known Variables?

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To calculate exhaust flow rates, it is essential to assume no losses from blow-by gases or valve leakage and to maintain perfect stoichiometry. The mass of exhaust gases can be determined from fuel consumption measurements, while the density of the exhaust gases is needed to find the volume. The ideal gas law can be applied to derive the density based on known temperature, pressure, and chemical composition. The relationship between mass flow rate and volumetric flow rate can be expressed as ##\dot{m}=\rho \dot{V}##. Understanding these principles will aid in accurately calculating exhaust flow rates.
Lavid2002
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Hello everyone,

I have been trying to calculate some exhaust flow rates for a while, and I am having some issues here. I was wondering if anyone could provide any insight.

I am making a few assumptions for this calculation. I am assuming no fuel or air is lost through blow by gasses into the crank case or through valve leakage. I am also assuming perfect stoichiometry. In other words...

Mass in = Mass out
All the fuel is burned in a perfect ratio of reactants

I know the mass of the products entering the engine through fuel consumption measurements, and stoichiometry assumptions.

Since I know the mass of my exhaust gasses all I need to do is determine the density of my exhaust gasses to find the volume.

What I know -Temperature
-Chemical composition
-Pressure
-Mass

What I need to know
-VolumeAny tips? I want to use the ideal gas law, but I don't know if this would be an appropriate application of it.

Thanks!

-Dave
 
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##\dot{m}=\rho \dot{V}##, where ##\dot{V}## is the volumetric flow rate, ρ is the gas density (from the ideal gas law), and ##\dot{m}## is the mass flow rate.

Chet
 
I do not have a good working knowledge of physics yet. I tried to piece this together but after researching this, I couldn’t figure out the correct laws of physics to combine to develop a formula to answer this question. Ex. 1 - A moving object impacts a static object at a constant velocity. Ex. 2 - A moving object impacts a static object at the same velocity but is accelerating at the moment of impact. Assuming the mass of the objects is the same and the velocity at the moment of impact...

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