Jim,
In unlimited air racing we use(d) (it's been a while for me) a water
spraybar system on the radiator to drop the coolant temp and fool the air
door into being closed at speed. This added 5-10 MPH to the P-51D that I
was crew chiefing.
The way we determined how much water to run was by watching the door at
speed and adjusting water volume accordingly to keep it closed. Depended on
how much power we were producing (as it would with your application). The
other factor was how much water we could carry in a wing (gun) bay. 45 gal.
All that this means is....try it at a known setting and then change it and
see what happens. How much water can you carry? HP output goes up and temp
goes up and spraybar water volume goes up to maintain a constant temp.
Chuck has the right approach. I think that I'd use a pump though. It'll
take a pass or two to get it the way that you want it.
The spraybar(s) should be located a few inches upstream of the fins to
allow some fogging with high enough pressure and small enough holes. This
was very important to the Mustang radiator. Dribbling didn't work very
well. Rules?
I know a really good thermo guy in the Skunk Works.
Skip Higginbotham......Bastrop, Texas
At 06:20 PM 11/18/99 , you wrote:
>Jim,
>
> That's a great question! How does evaporative cooling work on bikes?
>That oughto get engineers heads spinning. It's great to see what those guys
>can do with numbers. I'm no whiz at these things, so I just use my
>imagination and the old trial-and-error method. With an accurate way to
>monitor the temperature of the fins during the run you could devise some
>sort of pressurized delivery system. (the rubber diaphram type brake bleeder
>ball comes to mind, or just a big water bottle inside your leathers that you
>lean forward on.) Tubes with drilled orifices would direct water onto the
>fins during a pass. Too hot? Drill more holes in the tube. (Or lean on the
>water bottle a little harder.) How about ice water or different
>non-flamable cooling agents? The BIG question, and the one I hope will
>bring any lurking bike folks out of the shadows, is this; Is it LEGAL in
>your class?
>
> Bikes are lots of fun to watch, (although I get scared at 35 MPH on a
>moped) but from what I've seen the class competition is fierce, especially
>in the stock classes.
>
> Here's another question to stir up Cycle folks. In a stock class bike
>with a gravity fed fuel system, is it illegal for the rider to pressurize
>the fuel tank by blowing into the tanks vent hose during a run to keep fuel
>supplied to the carb? The bike is still stock, and only the riders lungs
>provide pressure to the tank. I've probably blown someones speed secret
>wide open with this, but I actually managed to limp a car home by using lung
>pressure to supply fuel to the carb, (after an electricic pump failed) and
>that's where the idea originated.
>
> Maybe a few words on the lists that Harley and other bike enthusiasts
>subscribe to could bring more interest in bikes to the land-speed list. It
>could also help to spread the word about LSR and get new folks out to
>events, which is always good. It's not tough to get the word out, just look
>at how THIS list has grown! In all the grassroots motorsports events in
>which I participate, none has the ability to spread its' message through
>various media as effectively as LSR. Why is that? The people. No doubt
>about it, the finest, most interesting bunch of racing enthusiasts anywhere
>can be found at land-speed events. We also have a recognizeable goal..."Go
>faster." (SAFELY) That's a lot easier to explain to someone than that sea
>of orange cones that face you at an autocross event.
>
> There are motorcycle racers out there somewhere who are desperate for a
>forum like this, we just need to invite them in.
>
>Chuck Rothfuss
>Pole Cat Hollow, NC (Where the US Post Office CLOSES for lunch.)
>
>
>
>
>
>
>
>At 11:47 AM 11/18/1999 -0500, you wrote:
>
>>LIST;
>>I have followed with great interest the discussions and formulas for cooling
>>needs, do any of you have formulas for how much water I need to spray on the
>>fins of my harley to keep it below 200 degrees on a 110 degree day at Maxton
>>in July
>>
>>
>>
>>Jim from Salem VA
>> P.S. wheres all the motorcycle guys on the
>>list
>>-----Original Message-----
>>From: Keith Turk <kturk@ala.net>
>>To: Higginbotham Land Speed Racing <saltrat@pro-blend.com>;
>>land-speed@autox.team.net <land-speed@autox.team.net>
>>Date: Wednesday, November 17, 1999 7:35 PM
>>Subject: Re: Cooling
>>
>>
>>>Hey SKIP.... aren't you the guy who said.... and I quote... " Keith you
>>>boys have any trouble coming through Texas.... give me a call"
>>>
>>>I have that ugly ole little White Camaro that has the Red on the back....
>>>called the So Al Special...(currently the semi special)
>>>
>>>Keith Turk
>>>Enterprise Al... formerly from Cerritos / Long Beech/ Alhambra Ca.... oh
>>>and pitch in Reno Nv and Sacramento Ca.... as a kid.... you think that's
>>>bad you oughta see my 20yrs of military bases... all over the damn
>>>world....
>>>
>>>----------
>>>> From: Higginbotham Land Speed Racing <saltrat@pro-blend.com>
>>>> To: land-speed@autox.team.net
>>>> Subject: Cooling
>>>> Date: Tuesday, November 16, 1999 6:55 AM
>>>>
>>>> Hello team,
>>>> This is my first "chat" attempt so please bear with me.
>>>>
>>>> It seems to me that actual data could help with the establishment of
>>>> cooling medium requirements.
>>>> Our data is as follows:
>>>> 300" SBC unblown on ERC 110 (400 Ft/lbs?)
>>>> Start line temp 150 F
>>>> 5 mile temp 210 F
>>>> Delta T= 60 F
>>>> Aluminum tank 9 gal
>>>> Aluminum heads
>>>> 6 gal/min circulation (circulates about twice on a run)
>>>> Anti-rust agent in water
>>>> Pro-blend in crankcase (controls internal engine heat better).
>>>>
>>>> Anyone else care to share? I'm building tanks for the front engine now
>>>but
>>>> will wait to see what others are doing. I'd like to minimize the volume
>>>> since I have already minimized the available space!
>>>>
>>>> Skip Higginbotham
>>>> AA/(B)GS 4411
>>>>
>>>>
>>>>
>>
>>
>>
>>
|