posted
i actually have a little project in the works. i want to find out what the theoretical max port area is, as the air in the port is a fluid and the walls of the port slow the air down (no slip condition). therefore the area of the port walls could be a factor in decreasing the efficiency of the energy transfer.
the theory is to expand the port area (theoretically) until you find a port interior surface area that is unefficient enough such that it will offset the increasing efficiency of the acoustical pressure coupling between the port and the airspace of the vehicle.
however i am not very well versed in this discipline so i wonder if perhaps someone else can try this.. because i'm not even sure if the non-slip condition would enter in as a factor... but once you get an absurdly long port there are factors such as pressure drop (a measure of decreasing efficiency) and sh1t pertaining to the mass in the port but i'm not all that sure, as i've said i'm not well versed in acoustics.
Posts: 1467 | From: eureka, ca | Registered: Aug 2001
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posted
oh yeah sorry- you would theoretically have to fix the box volume and assume a certain airflow (SPL).. becasuse both port wall area and thus airspeed depend on these values. there is no other way to find the port area variable without these being fixed unless you were to devise some sort of computer analog which would probably take years and years Posts: 1467 | From: eureka, ca | Registered: Aug 2001
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posted
At a certain point, generally accepted to be about 1.5*cone area, you get diminished results to the point that the amount you add in port area would be better spent on box volume.
-------------------- Jeff Sony CDX-780 Avionixx 600.4 Avionixx 400.2 2 Avionixx 800.2 2 ed 15a.22 All I want is 150, and I'll be happy
Official Member: SAVE THE BACK SEAT FOUNDATION Posts: 551 | From: Cali-fornicate | Registered: Oct 1999
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posted
is it really 1.2 times the cone area for the port size???? i have 2 rfl with a vent of 0.475m^2 !! is it wrong ?
Posts: 8 | From: belgium | Registered: Mar 2002
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quote:Originally posted by mtxbelgium: is it really 1.2 times the cone area for the port size???? i have 2 rfl with a vent of 0.475m^2 !! is it wrong ?
is what wrong? the RFL's or the port area?
Posts: 1467 | From: eureka, ca | Registered: Aug 2001
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