ELectric Fans on a Cummins ?
For $600 or so FLex a lite makes a fan kit for the CUmmins 5.9 Anybody using it? is there a noticable MPG gain running empty? Does it work well enough to cool the truck when loaded?
Forum Discussion
Not writing for the OP...he's going to do this no matter and am writing
for those who might also be considering, but needing a bit of engineering
info
Fluid coupled fan clutches range from about 10% coupled (min...or
not turned on) up to 50%-60% coupled (full on) for standard duty. HD and
severe duty are about 70%-90% coupled (full on). Both also down in the
mud when turned off (about 10% coupled). The difference
between HD and Severe Duty are in the shaft bearings and retainer...if
not bigger bearings...the airplane like fan blade will wear out the
smaller bearings of the standard duty shaft bearings & retainer and
allow the fan blade to take off and punch through the radiator...been
there done that with my MGB...put on a fiberglass 9 blade and after
a few thousand miles...the water pump bearings gave out and the blade
flew through the radiator
Coupled meaning whatever from the belts (V or serpentine) multiplied
by the dia ratio between the fan clutch's pulley dia vs the dampener
pulley's dia
OEMs have been playing around with the coupling and set points. So some
OEM are not standard off the shelf (std duty, HD or Severe duty).
The electric fan clutches must be either off or on, my guess. If there
is a variable coupling, then it's going to be expensive and why guessing
digital...on or off. There might be some parasitic loading and therefore
spins the fan a bit. Guessing down in the mud like fluid coupled...5%-10%
The plenum (ducting around the radiator for the fan blade) is designed
for 'that' fan it came with from the factory
Changing even the fan blade can upset that plenum. Plus there is noise
mitigation in it's design. The Duramax had a huge problem with cooling
because their designers blew it on the plenum (ducting/shroud/etc)
There are other attributes and one key is where this OP is clueless
on. CFM is out of context without the 'head' spec for that CFM
'Head', as in restriction either/or/both negative (puller) or positive
(pusher) and in inches of water or mercury (big stuff)
Betcha the electric fan's 10,000 CFM is 'free air'...
Then the fact that most of the ones on the Flex-a-lite site for this
application has two fans. That makes it tougher to get a GOOD plenum.
There will be dead spots and if they are in the wrong places...may
create backpressure for spots on the radiator (meaning reduced air flow)
Also, note the sheetmetal for those two fans...the open area is reduced
and noodle how much LESS air flow on the highway...when even fan
clutches are turned off...
Anyone ever lift up a 1 HP (120 VAC) electric motor? Pretty heavy
and at 120 VAC, about TEN times smaller than a 12 VDC motor
that would be in any automotive radiator electric fan system. Or looking
at it the other way...a 12 VDC electric motor would be TEN times
larger than a 120 VAC motor (approx)
That is for a 12 VDC 1 HP electric fan motor. My Severe Duty fan clutch
takes +15 HP (it's rated up to 25 HP, but for the OP, kept it at it's
lower rating) and an 12 VDC 15 HP to 25 HP motor would be about +100 lbs
Also, anyone read the fine print in any of these electric radiator
fan assemblies? Hint...most don't use 12 VDC, but a bit higher. Why?
and does your TV's alternator/battery system provide that higher voltage
on a 100% duty cycle ?
Truly wish the OP would proceed with this and report back, often on
how it goes. Maybe I'm all wet and they have discovered some new
laws of physics for me to update my knowledge base and learn
something...like when the Japanese came out with air foil blades for
computer muffin fans!!! Revolutionized muffin fans. Then the swept
back blades, as they were spinning them so fast there were additional
turbulence (think jet airplane wings and why they are swept back)
for those who might also be considering, but needing a bit of engineering
info
Fluid coupled fan clutches range from about 10% coupled (min...or
not turned on) up to 50%-60% coupled (full on) for standard duty. HD and
severe duty are about 70%-90% coupled (full on). Both also down in the
mud when turned off (about 10% coupled). The difference
between HD and Severe Duty are in the shaft bearings and retainer...if
not bigger bearings...the airplane like fan blade will wear out the
smaller bearings of the standard duty shaft bearings & retainer and
allow the fan blade to take off and punch through the radiator...been
there done that with my MGB...put on a fiberglass 9 blade and after
a few thousand miles...the water pump bearings gave out and the blade
flew through the radiator
Coupled meaning whatever from the belts (V or serpentine) multiplied
by the dia ratio between the fan clutch's pulley dia vs the dampener
pulley's dia
OEMs have been playing around with the coupling and set points. So some
OEM are not standard off the shelf (std duty, HD or Severe duty).
The electric fan clutches must be either off or on, my guess. If there
is a variable coupling, then it's going to be expensive and why guessing
digital...on or off. There might be some parasitic loading and therefore
spins the fan a bit. Guessing down in the mud like fluid coupled...5%-10%
The plenum (ducting around the radiator for the fan blade) is designed
for 'that' fan it came with from the factory
Changing even the fan blade can upset that plenum. Plus there is noise
mitigation in it's design. The Duramax had a huge problem with cooling
because their designers blew it on the plenum (ducting/shroud/etc)
There are other attributes and one key is where this OP is clueless
on. CFM is out of context without the 'head' spec for that CFM
'Head', as in restriction either/or/both negative (puller) or positive
(pusher) and in inches of water or mercury (big stuff)
Betcha the electric fan's 10,000 CFM is 'free air'...
Then the fact that most of the ones on the Flex-a-lite site for this
application has two fans. That makes it tougher to get a GOOD plenum.
There will be dead spots and if they are in the wrong places...may
create backpressure for spots on the radiator (meaning reduced air flow)
Also, note the sheetmetal for those two fans...the open area is reduced
and noodle how much LESS air flow on the highway...when even fan
clutches are turned off...
Anyone ever lift up a 1 HP (120 VAC) electric motor? Pretty heavy
and at 120 VAC, about TEN times smaller than a 12 VDC motor
that would be in any automotive radiator electric fan system. Or looking
at it the other way...a 12 VDC electric motor would be TEN times
larger than a 120 VAC motor (approx)
That is for a 12 VDC 1 HP electric fan motor. My Severe Duty fan clutch
takes +15 HP (it's rated up to 25 HP, but for the OP, kept it at it's
lower rating) and an 12 VDC 15 HP to 25 HP motor would be about +100 lbs
Also, anyone read the fine print in any of these electric radiator
fan assemblies? Hint...most don't use 12 VDC, but a bit higher. Why?
and does your TV's alternator/battery system provide that higher voltage
on a 100% duty cycle ?
Truly wish the OP would proceed with this and report back, often on
how it goes. Maybe I'm all wet and they have discovered some new
laws of physics for me to update my knowledge base and learn
something...like when the Japanese came out with air foil blades for
computer muffin fans!!! Revolutionized muffin fans. Then the swept
back blades, as they were spinning them so fast there were additional
turbulence (think jet airplane wings and why they are swept back)
