Yes, absolutely..
to make any gas flow from one direction to the other we need a differential of pressure.
to know the gain to an engine we need to know the amount the pressure differential has increased. without a difference of pressure there is no flow, and, flow stops when the pressure differential equalises.
so, any benefit to an N/A engine is going to be caused by, and proprtional to, an increase in pressure. Which is itself directly proportional (in this instance) to the compressability of the air molecules.
If we can quantify this pressure then we can quantify a gain.
but, the resistance of air - or its compressability, is being overestimated by the guys who think an increase occurs. Without a compressive effect, there is NO increase in pressure (Basic gas laws)
Aerodynamic forces also depend in a complex way on the compressibility of the air. As an object moves through the air, the air molecules move around the object (outer and inner). If the object passes at a low speed (typically less than 200 mph) the density of the fluid will remain constant. But for high speeds, some of the energy of the object goes into compressing the fluid and changing the density, which will alter the amount of resulting force on the object.
In other words, the amount of compression is so negligable as to be immaterial until (for a car !) a high speed is achieved.
So, to be certain there is no measurable benefit on a road car all we need to do is measure the pressure increase occuring. If its hardly registering, its doing nothing positive for us.
Also, we then come to the problem of the pulse progression in the inlet system as a whole (this is the good bit lol !).
as a column of air is used by the engine a large vacuum (Differential) occurs and this is used to cause the atmospheric air to re-fill the column ready for the next charge load. As this charge fills, the pressures equalise again and flow stops momentarily. The only pressure increase again can be from the compressability of air at the intake mouth. The pressure differential caused by the vacuum is great (orders of Magnitude greater than any compressability of the air at the mouth or scoop or whatever)
As forward speed increase to around the 200 mph mark the density of the air can be increased by the ram effect in the scoop.
Below that we are simply platting sawdust !.
again, a simple measurement of the pressure with a monometer (a few quid to make) is all that it needs to show this in action.
and, we havnt even considered the effect of non constant airflow at the scoop mouth to a foward facing airflow and the effects on the linearity of the airflow (how stable and repeatable it is)
Joe.
