With reference to post #242, posted by Tanimbar:
quote:
"Bsieker, you wrote:
"It is my understanding of the water scavenge jet pumps that they would, while trying to keep the water emulsified in the fuel, would also mix the fuel, preventing stratification."
Thanks for that. Can anyone comment on how these pumps operate and to what 'depth' in the fuel their effect is propogated? Are they designed to fully mix fuel within the total volume of the tanks and so prevent stratification?" unquote
The water scavenge jet pumps take fluid from the lowest points in the tanks (1 in each main wing tank and 2 in the center tank) and send it to the fuel pump inlets. This prevents water from collecting at the bottom of the tanks. The water scavenge pumps are jet pumps and operate automatically when the fuel pumps are on. They use fuel from the fuel pumps as motive fuel. The flow of the motive fuel through the jet pump causes suction that takes fluid from the lowest point in the tanks.
If a water detector finds water in a tank, the fuel quantity processor unit (FQPU) causes the water detection message for a particular tank to show. The main tank water detection messages show at the bottom of maintenance page 1. The center tank water detection messages show at the bottom of maintenance page 2. The amount of water required to show the L MAIN WATER or R MAIN WATER message is approximately 7 gallons. The amount of water for the center tank message is approximately 138 gallons.
Regards,
Green-dot
Last edited by Green-dot; 21st Feb 2008 at 22:48.
Reason: correction in text.