intake port Re No

[rpmag]

Intake port Reynolds numbers seem to be well in the turbulent range and not laminar (though they may be smooth and well formed). It has been suggested to me that this turbulent flow may have some advantages (over laminar) for fuel homoginisation, is this a reasonable suggestion?
Also the port conditions being turbulent would seem to suggest that flow seperation/shear would be more likely given local disturbances such as port mismatch and surface irregularities?

 

[rpmag]

The above has been confirmed to a limited degree by a member. Thank you.
Re for the port were in the 25,000-190,000 range.
It would seem that many of the 'tuning' books that say 'Laminar' are simplifying the term, though some may simply be ignorant of the facts....a slightly worrying thought.

 

[patprimmer]

I would also expect that throttle plates and valve guides and stems are a bit disruptive to laminar flow.

Regards
pat pprimmer@acay.com.au
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[rpmag]

it would certainly be disruptive to smooth flow and I have been told that the disruption generated may take up to 10 diameters (of the port) of port length to return to smooth well formed flow. Hence the attention given to butterfly placement