Does anyone know by what method and sensor GAMI is able to measure the
cylinder pressures? Does it use the SAAB method (in their turbo cars
now, they measure it for knock prevention that way instead of a noise
knock sensor) of a resistance wire or is it more direct? Inquiring minds want
to know.
Marc Wiese
[Nope, spark plug electrode has been around for years, hence the Chinese
TV on the old piston airline transports. GAMI uses a fiberoptic
pressure transmitter, attached to a special Champion sparkplug that has
a socket for same. Turns out you can use fibers to sense temperature or
pressure. We drop 'em down the oil wells now to get a
temperature/pressure profile every foot (!) down the bore hole.
Paul
Paul,
This is another knowledgeable Paul and I was curious on how it is being
done by gami. Keep this in mind, I think gami will certify the system
using this system this year or very soon.
Marc Wiese
This is what I found with a google search.
Paul Lamar
******************************************************************
http://wwwnt.if.pwr.wroc.pl/up/instytut/Abstracts9.htm
1. Highly sensitive fiber-optic sensor for dynamic pressure measurements
M. S. Nawrocka, W. Bock, W. Urbańczyk, J. Wójcik, Proc. SPIE, 3745, pp. 293-297, 1999.
A new type of fiber-optic pressure sensor based on highly birefringent fibers is presented. To
assure temperature desensitization, the sensing part of the
device is composed of specially developed side-hole fiber and elliptical core fiber, which are
spliced to each other with polarization axes rotated by 90.
Such sensor construction assures high pressure sensitivity and compensation of temperature effects
associated with rapid pressure changes. The sensor
allows for unambiguous and fast phase shift measurements in the range from -/2 to +/2 with a
sampling rate of 5 kHz and resolution of about 0.5% of
full scale (210-3 atm). The sensor calibration procedure, responses to fast pressure change, and
preliminary applications are demonstrated.
*******************************************************************
The AirCraft Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/
Copyright 1998-2002 All world wide rights reserved.