Alternate to Air Cooling Re: <VV> Electric cooling fan results

[Tony Underwood]

At 07:12 PM 8/1/2007, FrankCB at aol.com wrote:
>
>Tony,
>     You're missing the point!  Ton K. was able to  extract so much HP from
>the Corvair engine by using major quantities of WATER  injection into the
>combustion process.


No, that didn't escape me.   Water-meth injection has been around a 
long time and my associations with aircraft engines has long since 
brought to surface the merits of water injection to control 
combustion/detonation and head temps via a variety of different 
factors including getting the timing up to where max efficiency cam 
be maintained while controlling detonation which means COOLER 
running.   It also could add as much as 400 hp to some of the radial 
engines found in some WW-II fighter planes and bombers, *without* 
adding a lot of excessive heat.

I'm with ya...  :)

By the way:   Water-meth mix was the choice for aircraft although 
water alone likely would work just as well... except for the fact 
that at 20,000 ft in January the outside temps are sometimes as low 
as -40, thus the addition of alky to the mix.


>As that great automotive pioneer  Sir Harry Ricardo proved many
>years ago, on a turbocharged engine you can make  MAJOR increases in TORQUE
>(what engineeris call BMEP) without having to enrich  the A/F mixture and
>without increasing the PEAK combustion pressure that  make 
>detonation and break
>things.
>     If it was good enough for Tom K. and Harry Ricardo  as well as over
>20,000 of our WW2 fighter planes,

...AND bombers...


>it should be good enough for  us.
>     Evaporating water cools a lot better than ambient  air flow.


Agreed... but if you're on the highway headed to an out-of-state car 
show in your electric-fan cooled 'Vair, how much water is it gonna 
take?   And the fact remains that in performance use the stock fan 
still requires respectable horsepower to run at higher rpm, power 
that might be needed to make the difference between 1st Place and 
"who else was running?".   Again, I understand how water injection 
improves combustion under load as well as contributing to allowing 
tuning conditions which help cool the engine.    I *also* understand 
that the issue for performance applications revolves around 
eliminating the <10 HP drain, sucked up by that fan at high rpm.

By the way:   I still stand by the notion that the electric fan would 
NOT have kept TK's 'Vair from overheating drastically under the 
conditions he faced during the high speed runs, regardless of how 
much water went through the engine...unless of course it was being 
sprayed on the heads.  ;)    That is my position, as regards how he 
may well have gone even *Faster* if he could have eliminated the drag 
on his engine caused by the cooling fan.


Let's not forget that the point here (as I see it) is to eliminate as 
much power loss from the engine as possible.   Several guys in here 
went to some trouble to try an electric fan system to see just how it 
might work in real-world testing.   Again, it came close to being 
functional.    I think they did a good job with what they had to work 
with.   And they did NOT get to exploit all the options they had 
available to them, which means there's wiggle room here to do more.

THAT alone means that there's more to this story that remains to be 
looked into.


Hey, previously I was a detractor, didn't think anyone could figure a 
way to cool the engine adequately with electric fans without needing 
a big alternator (or seriously stress a stock alternator) which 
itself would drag down the engine.   More efficient fans and motors 
combined with some force-fed air from somewhere could well prove to 
be successful for streetable applications as well as off-road 
performance stuff.


tony..          well aware that many people are long since sick of 
this thread