----- Original Message -----
From: "Steve Laifman" <SLaifman@socal.rr.com>
To: "Tom Witt" <wittsend@jps.net>
Cc: "Tiger's Den" <tigers@autox.team.net>
Sent: Wednesday, October 16, 2002 11:15 AM
Subject: Re: Fuel vapour, non tiger
A mass flow meter is installed in the air intake
> system that measures the velocity and temperature of the entering air
> flow, with a known cross section - hence mass air flow rate. By knowing
> the "target" air/fuel ratio, an appropriate mass of atomized fuel is
> added with known mass (temperature / density / volume).
What you call a mass flow meter better describes the Speed/Density system
used by Ford prior to about 1989.
The mass air flow meter is a hot wire anemometer. It measure the current
required to keep the wire at a constant temperature. The amount of heat
lost from the wire is directly related to how many molecules of air are
going by. ie the MASS of air.
Erich
|