The 24 Hours of Lemons Forums → Lemons Tech → Water Cooled Brakes
I helped put together such a system in the early 80's for a Porsche; we used a windshield washer tank that had an integrated pump, and I am not sure where they got the nozzles. They emmitted what appeared to me to be a very fine mist.
The relay driving the pump was wired to the brake light circuit.
I don't remember much more about it...
Cheers
RIch B
Corvair engine fan:
Surely if you can build a junkyard race car that'll last 24 hours you can make 4 of these. 
If you want to build a water mister setup, Harbor Freight etc sell 'swamp cooler' kits which mount on a high velocity fan. They use brass nozzles that spray a fine mist.
chicagozer wrote:There is some precedence for that approach.
I'm pretty sure that F1 did something with outside wheel brake ducting. They called them "rim shields" or something like that. So just hire a former F1 wheel engineer and you've got the problem solved.
Yup ...
http://www.f1technical.net/development/178
I'll chime in here. I'm ok with water cooled brakes if you can show me that the water will not get onto the track in significant enough amounts to cause a track surface problem.
I'd really prefer not to have them, but I'll consider well engineered solutions.
John
Maybe fuel injectors for the nozzles?
Maybe fuel injectors for the nozzles?
Water injectors... He already has pressurized water for his water injection system. I imagine that he is just going to run some more high pressure tubing into the wheel wells and have sprayers set up.
I'll chime in here. I'm ok with water cooled brakes if you can show me that the water will not get onto the track in significant enough amounts to cause a track surface problem.
I'd really prefer not to have them, but I'll consider well engineered solutions.John
we can do a well engineered solution. in 6-8 weeks i'll present our plan.
stimpyvan wrote:Maybe fuel injectors for the nozzles?
Water injectors... He already has pressurized water for his water injection system. I imagine that he is just going to run some more high pressure tubing into the wheel wells and have sprayers set up.
yep. fuel injectors will rust shut if you run water through them (at least that is what i read when researching water injection systems) and i don't want to control the injectors with precious PWM channels, in any case. i have misting nozzles from McMaster that i plan to use with a pair of solenoids. i'm trying to figure out the amount of water to spray with a given pressure, though. I've emailed the Ford Racing V8 Supercars team. maybe they will respond..
Long shot for misters, but those spray nozzles for the backpack weed killers might work as well. If you turn the outside of them, it adjusts the spray pattern. Tight pattern + high pressure might = mist.
A slightly different take on water cooled brakes from the book "Brake Handbook" by Fred Puhn
"One of the latest tricks for cooling brakes is water cooling. A device is used to spray water into the brake-cooling ducts. The water vaporizes in the duct and cools the incoming air. Squirting water directly on the rotor has been used for years with varying degrees of success. The idea with this new systems is not to squirt water directly on the brake. Steam formed will not cool the brake as efficiently as air. Also, it may cause the rotors to crack. Instead, the water is strictly an air cooler." "..... First, make sure the air ducting is sized and sealed correctly, and the inlets are in a high pressure area. Also, be sure the wheels are vented correctly. If all this is not enough, then try water cooling. Because the water-cooling system is meant to cool the air in the brake-cooling duct, the system only works well on hot, dry days. If the air is cool and damp, little extra cooling is done. On a hot, dry day, water cooling can make a considerable difference." © Fred Puhn, "Brake Handbook" (page 147)
A slightly different take on water cooled brakes from the book "Brake Handbook" by Fred Puhn
"One of the latest tricks for cooling brakes is water cooling. A device is used to spray water into the brake-cooling ducts. The water vaporizes in the duct and cools the incoming air. Squirting water directly on the rotor has been used for years with varying degrees of success. The idea with this new systems is not to squirt water directly on the brake. Steam formed will not cool the brake as efficiently as air. Also, it may cause the rotors to crack. Instead, the water is strictly an air cooler." "..... First, make sure the air ducting is sized and sealed correctly, and the inlets are in a high pressure area. Also, be sure the wheels are vented correctly. If all this is not enough, then try water cooling. Because the water-cooling system is meant to cool the air in the brake-cooling duct, the system only works well on hot, dry days. If the air is cool and damp, little extra cooling is done. On a hot, dry day, water cooling can make a considerable difference." © Fred Puhn, "Brake Handbook" (page 147)
funny! i just got this book from amazon a couple of days ago. This section is really anecdotal. I also find it very hard to believe that all of the water vaporizes in the duct before hitting the rotor. The fresh air coming into the duct is ambient temperature. i can spray water mist outdoors and it doesn't completely vaporize until alot of time or alot of heat has done it's work.
gump wrote:A slightly different take on water cooled brakes from the book "Brake Handbook" by Fred Puhn
"One of the latest tricks for cooling brakes is water cooling. A device is used to spray water into the brake-cooling ducts. The water vaporizes in the duct and cools the incoming air. Squirting water directly on the rotor has been used for years with varying degrees of success. The idea with this new systems is not to squirt water directly on the brake. Steam formed will not cool the brake as efficiently as air. Also, it may cause the rotors to crack. Instead, the water is strictly an air cooler." "..... First, make sure the air ducting is sized and sealed correctly, and the inlets are in a high pressure area. Also, be sure the wheels are vented correctly. If all this is not enough, then try water cooling. Because the water-cooling system is meant to cool the air in the brake-cooling duct, the system only works well on hot, dry days. If the air is cool and damp, little extra cooling is done. On a hot, dry day, water cooling can make a considerable difference." © Fred Puhn, "Brake Handbook" (page 147)
funny! i just got this book from amazon a couple of days ago. This section is really anecdotal. I also find it very hard to believe that all of the water vaporizes in the duct before hitting the rotor. The fresh air coming into the duct is ambient temperature. i can spray water mist outdoors and it doesn't completely vaporize until alot of time or alot of heat has done it's work.
Water vaporization might be different in air with a high velocity, lots more air to pick up the water. The pressure change might help too. Also, Id guess you turn the sprayers on once at race speed and turn it off under red flag/ pits to eliminate puddling.
Olaaf, did you check out the wilwood check valve/brake fluid recirculator/auto bleeder setup? http://www.wilwood.com/PDF/DataSheets/ds213.pdf
Water vaporization might be different in air with a high velocity, lots more air to pick up the water. The pressure change might help too. Also, Id guess you turn the sprayers on once at race speed and turn it off under red flag/ pits to eliminate puddling.
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could be.. i'll test it with a length of duct and a blower fan. but i'll wager that the mist will puddle and collect at the other end of the duct.
Olaaf, did you check out the wilwood check valve/brake fluid recirculator/auto bleeder setup?
i did, it looks pretty cool. However, with my new found book knowledge on braking system i think i found a couple of things i did wrong that we need to address before a further customization of the brake lines. I'm pretty sure i blocked the compensating port in the master, and i stepped down the size of the main front circuit from the master to the prop valve, which raised braking pressure, but lowered fluid displacement volume, which gives you a long pedal. I also think i have a tiny leak in the brake lines that we need to track down. Our goal is to get a firm pedal at the start of the day, and then see how/if it degrades..
The 24 Hours of Lemons Forums → Lemons Tech → Water Cooled Brakes
