View Single Post
Old 10-12-2009, 01:58 AM   #34 (permalink)
Frank Lee
(:
 
Frank Lee's Avatar
 
Join Date: Jan 2008
Location: up north
Posts: 12,762

Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

Moon Unit - '98 Mercury Sable LX Wagon
90 day: 21.24 mpg (US)
Thanks: 1,585
Thanked 3,555 Times in 2,218 Posts
Some water pump stuff:

Inside BMW's Latest Powertrain Technologies

Water Pump Tech

OK here, from a piece regarding sensors for centrifugal water pumps:

Quote:
Alternately, low load sensors can detect:• Minimum flow• Dead-heading• Flow restriction (i.e., plugged discharge filter or strainer,clogged spray nozzles, closed discharge valve, etc
http://www.warrender.com/upload/prod...28dab2a7fd.pdf.

So me thinks automobile water pumps could cavitate just like that hair dryer and not like that boat, were flow to be stopped.

But then... the flow isn't ever stopped even when the stat is closed. Circulation is constant through head and block.

Now I think whether t-stat is open or closed likely has very small effect on pump load- too small to matter. For what my opinion on that is worth.

And:

Quote:
In centrifugal pumping applications with no static lift, power requirements vary, as the cube of the pump speed and small decreases in speed or flow rate can significantly reduce energy use. For example, reducing the speed (flow rate) by 20% can lower input power requirements by approximately 50%.
http://www1.eere.energy.gov/industry...pdfs/38949.pdf

Combine that with the SuperChevy dyno stuff, and underdriving the water pump can save HP but don't do it at the expense of low rpm cooling. And they didn't even bother reporting testing below 3000 rpm cuz it was too small.
__________________



Last edited by Frank Lee; 10-12-2009 at 05:12 AM..
  Reply With Quote
The Following User Says Thank You to Frank Lee For This Useful Post:
Piwoslaw (10-12-2009)