View Single Post
  #2  
Old 24-06-2004, 03:27 AM
cheekychimp cheekychimp is offline
Member
 
Join Date: Jun 2004
Posts: 39
Default

You might want to ask "hotrod" specifically as he is more knowledgeable than me. If however I am to understand correctly what he has told me before, I would sum up this theory in the following manner:-

All liquids have relevant freezing and boiling points. They also have points of vapourization dependant upon both temperature and pressure. By this I mean water in the cooling system remains liquid under pressure despite the fact that it's temperature is above 100 degrees celsius.

In the example above, water below 100 degrees would remain as a liquid. Unquestionably the excessive temperatures inside the combustion chamber would vapourise the water, but from a physics point of view, I would not have thought that the pressure drop would be a significant factor in the process of vapourization once the inlet valves are open because air is being drawn into the chamber replacing the 'vacuum' or low pressure area that would other wise exist.

The Volumetric Efficiency issue is more complicated. An increase of Volumetric Efficiency caused by evaporation inside the combustion chamber will probably occur but would be minimal at this point. Far mor important from a VE point of view I would have thought is the cooling of the air intake tract creating denser air 'ready' to be sucked or forced into the combustion chamber on the intake stroke.

What I am saying here is that, if air enters the combustion chamber at 70 degrees celsius (theoretical example) far more will get in than if that air was at 140 degrees celsius.

WI has been proven as an alternative to intercooling, but I would suggest on the basis of what I have read that it is only effective in suppressing detonation by reducing heat in the combustion chamber and NOT in increasing VE by reducing heat in the intake tract.

But I would welcome other views.

Paul.
Reply With Quote