----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]----
Larry, The size of the impact orifice shouldn’t matter unless the size and potential flow into the container is in the same order of magnitude as the flow out of the container. A LOT of air could be rammed into the vent hole, I’d bet, compared to the flow rate of the fuel leaving the tank. So, for practical purposes, it’s a static system. Ed Burkhead http://edburkhead.com/ [EMAIL PROTECTED] (remove the QQQ) -----Original Message----- From: MAGIC VAC [mailto:[EMAIL PROTECTED] Sent: Friday, April 09, 2004 12:12 PM To: Ed Burkhead; Coupe-Tech Subject: [SPAM] Re: [COUPERS-TECH] Mysterious fuel problem Egads, It'd take me years to figure what you've just figured. (10 minutes to do the calculations, 2 years of higher education to learn how to do it) But, with all you've said, did you take into account the size of the impact orifice? Larry ----- Original Message ----- From: Ed Burkhead <mailto:[EMAIL PROTECTED]> To: Coupe-Tech <mailto:[email protected]> Sent: Friday, April 09, 2004 11:04 AM Subject: RE: [COUPERS-TECH] Mysterious fuel problem ----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]---- Larry, Actually, the exact amount could probably be computed with the right table. What’s the ram-air-pressure of 108 mph? It’s measured by every air speed indicator. Source: http://www.ssec.honeywell.com/pressure/datasheets/AN104.pdf Impact Pressure qc In Inches of Mercury for Values of Calibrated Airspeed Vc in Miles Per Hour Calibrated Airspeed, Vc, mph 0 1 2 3 4 5 6 7 8 9 100 .363029 .370347 .377736 .385239 .392785 .400406 .408111 ..415888 ..423736 .451639 110 .439637 .447433 .455874 .464097 .472391 .480772 .489213 ..497731 ..506328 .515008 120 .525742 .532566 .541464 .550443 .559480 .568606 .577797 ..587070 ..596414 .605837 It looks like 100 mph gives .363029 inches of mercury and 110 gives 439637 inches of mercury. Now, we get from http://www.wiredwales.com/info/c_factor/pressure.htm Inches of mercury Pounds/sq. in. 0.4912 one inch of mercury = .4912 psi 100 mph --> .363029 inches of mercury times .4912 psi/inch of mercury = ..178312 psi. A little less than two tenths of a pound per square inch. 110 mph --> .439637 * .178312 = .216 psi.
