Landracing Forum
Tech Information => Technical Discussion => Topic started by: awelker on September 06, 2013, 12:30:03 PM
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I am looking into converting my Flathead Ford V8 powered bellytank to a radiator in a tank cooling system. Currently I have two 6" x 16" radiators with small electric fans (about 600cfm each) which proved to only barely keep it cool for 3 miles. Also the current setup has 2 Aerospace Components electric water pumps that each feed one radiator and one bank of the engine.
Space is limited and I have come up with enough room for a tank that would hold about 11 gallons and have a radiator with a 7" X 13" core dimension sitting horizontally in the bottom of the tank. I can calculate the amount of Btu's the 11 gallons would absorb from and ice mix to a partial boil off which I think will be sufficient, but would that size radiator in the tank be large enough to dump the heat from the engine water to the cooling tank water quick enough? Also, I would be switching to one inline electric water pump from Stewart and adding thermostats to the outlet side of the cylinder heads.
Looking for what some others have done and how it has worked out for them, any real world experience is appreciated. To do this I need to relocate alot of stuff and I want to be sure it is a move in the right direction.
Andy
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Andy, I forgot to turn the pump on one :cry: time with 900 HP for 2+ miles at B'vill --my exit eng temps were 220 with 9 gallons of water and no ice with a closed radiator system with a 28# cap. yes the water in the box was boiling violenty as the boil temp at B'vill that day was 194 we now turn the pump on when we close the canopy. :-D
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Andy, I run a system real close to what you describe, right down to the Stewart water pump and a thermostat-I run both heads into one thermostat, then return to the tank.
It sure works great on the Caddy flathead, so I'm sure it will work great on yours!
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Is the 11 gallons the total water you are using or is that what is in the tank surrounding the radiator and you are going to pump into that tank from another source?
I made...
(http://purplesagetradingpost.com/sumner/Hooley%202013/rad-in-box-68.jpg)
...a radiator in a box for Hooley's Stude and we were very happy with how it worked but we are pumping water continuous through the box from a 30 gallon tank in the car. With the electric pump we are using for that we are only exchanging the water from the larger tank about 1 time during the run. Of course our combination is making much more heat from the motor than yours so the radiator and cooling water to the tank could probably be quite a bit less.
If you are only using the 11 gallons in the tank with the radiator sitting at the bottom and no circulation that might worry me. Although in theory you might not need other water and circulation as the hot water would keep rising to the top. I still think I'd want some circulation that is moving water through the core of the radiator in the box. Have you seen others with no circulation? Sparky has it but Buddy do you?
We are using a 2 pass radiator and passing the cooling water through it twice also. A belt driven pump on the engine for the coolant water from the engine to the radiator.
The radiator in water vs. air is very efficient.
(http://purplesagetradingpost.com/sumner/Hooley%202013/rad-in-box-35.jpg)
Here is a link to the rad-in-a-box I made.....
http://purplesagetradingpost.com/sumner/Hooley%202013/13%20-%20construction%20menu.html
.... you will find it down the page a ways,
Sum
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Sum, I don't have circulation in the box, but I do add ice.
I'm using a Ron Davis, 23x4x3.5 thick radiator.
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Sum, I don't have circulation in the box, but I do add ice.
I'm using a Ron Davis, 23x4x3.5 thick radiator.
Do you have a picture of the finished box that has the radiator in it? Thanks,
Sum
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Well, I'm definitely not making 900 hp, I'd need 3 more engines to come close... But the flathead does put alot of heat into the water.
The 11 gallons would be all I would have, no circulation in the box, no other room for additional water storage. Already need to relocate fire bottles and build a fuel tank, no more room left.
Buddy, how much water do you have in your box? If you start with ice how warm does your box water get after a run, any boiling?
Sumner, I considered boxing in my existing radiators and circulating though them from another tank, but if I keep those radiators I can't relocate my fire bottles and would only be able to carry about 5 gallons of water for circulation over the radiators. I like your setup, just wish I had some more room.
Radiator in water is very efficient, considered doing a chassis dyno test with existing radiators dipped in some open water tubs.
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Sum, I don't have circulation in the box, but I do add ice.
I'm using a Ron Davis, 23x4x3.5 thick radiator.
Do you have a picture of the finished box that has the radiator in it? Thanks,
Sum
Here you go Sum! If you notice, I run 2 radiator caps. The top cap is the return, and bottom the feed. The dual caps make 'burping' the engine very easy.
The electric pump to the left of the box feeds the mechanical H2O pump on the back of my dry sump.
Well, I'm definitely not making 900 hp, I'd need 3 more engines to come close... But the flathead does put alot of heat into the water.
The 11 gallons would be all I would have, no circulation in the box, no other room for additional water storage. Already need to relocate fire bottles and build a fuel tank, no more room left.
Buddy, how much water do you have in your box? If you start with ice how warm does your box water get after a run, any boiling?
Sumner, I considered boxing in my existing radiators and circulating though them from another tank, but if I keep those radiators I can't relocate my fire bottles and would only be able to carry about 5 gallons of water for circulation over the radiators. I like your setup, just wish I had some more room.
Radiator in water is very efficient, considered doing a chassis dyno test with existing radiators dipped in some open water tubs.
I have a 20 gallon tank, but could go smaller, if I didn't need it for ballest. The ice melts, but the water in the box stays cool to the touch-I'd guess 70-80 degrees. I'm also probably putting out about 700 HP at the moment, so I'm very hasppy with the setup!
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these radiators in boxes, dual caps, external
water tanks and whatnot ~~ very genius .
bf
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Flathead Henry engines need a bunch of cooling just because the exhaust ports wrap around the cylinders. Don't skimp when you build a system for it. Too much cooling isn't a problem.
Sid.
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.... considered doing a chassis dyno test with existing radiators dipped in some open water tubs....
If you can do that it would tell you a lot.
Buddy thanks for the pictures. Also there are pictures of Sparky's old rad-in-a-box here...
http://purplesagetradingpost.com/sumner/Hooley%202013/13%20-%20hooley-construction-2013-13.html (http://purplesagetradingpost.com/sumner/Hooley%202013/13%20-%20hooley-construction-2013-13.html)
Ours was made to go in a specific location, in the fender well next to the engine. Helps to get ballast forward on the car. The 28 gallon intercooler ice water tank is in the fender well on the other side and also helps to get ballast forward on the car. With a carefully made tank you can get quite a bit of water storage in an area that is fairly unusable for something else.
Sum
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Andy, did you make Speedweek this year? I was looking for you guys in my brief trip. This is a great thread, I am doing the rad in a tank as well. I copied Skips setup in his roadster in the build diaries.
http://www.landracing.com/forum/index.php/topic,6794.0.html
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Andy,
The "radiator in a box" style cooling system really has only one advantage over having a closed coolant system with a pressurized container, you don't have to build a container for the cooling water that has to operate at your engines cooling system pressure, that pressure is taken by the radiator that is in the box. The "box" system, if done correctly, does add additional complexity and size to the cooling system as you will need an additional water pump to circulate the water in the box through the radiator along with having a water pump to circulate the actual cooling water through the engine/radiator system. As you can see from the pictures of Buddy's system and the system that Sum built for Hooley's Studi they are not small. When Hooley was running a supercharged small block Chevy they ran a pressurized closed system using a 15 or 20 gallon air bottle that carried the cooling water and that was on an engine that made at least 800-900 horse power. I would think that for you going with a closed system would be the best approach. I feel that one of the biggest mistakes made in cooling systems is improper selection of the engine water pump capacity. The rule of thumb that works is: 10 gallons per minute per 100 horse power (thanks to Stu Van Dyne, Van Dyne Engineering for this information) . In your case your flatty may make around 200 horse power so 20 gpm is what you would need BUT this does not mean you can go to the Summit or Jegs catalog and just buy one of their 20 gpm electric pumps because the 20 gpm has to be at the pressure drop that is required to make 20 gpm actually flow through your engine and these pumps are rated at 20 gpm at zero pressure on the outlet. If you look at Buddy's system he has a pretty stout mechanically driven water pump that probably is capable of pumping 70-80 gpm of water through his engine at the pressure required to over come the pressure drop of going through both the engine and the "radiator in a box" system. So knowing the actual output flow of your water pump at your systems back pressure based upon the flow rate is very important and most of the electric pumps you can buy will not provide you with this information. If you go with an electric pump and the manufacture cannot or will not provide you with the flow vs. out put pressure capabilities of their pump than I would start by buying a pump that is at least 2-3 times your required flow rate and remember that the 10 gpm/100 hp rule is a minimum so if you have more flow than that the system will only work better. Water flow through your engine and the radiator needs to be turbulent to be efficient.
The other recommendation that I would have is to use a BMW 320 I three way thermostat. These are really cheap, about $20, and what they allow you to do is to have full pump volume water flow through the engine while the engine is warming up as opposed to "normal" thermostats that "lock" the water in the engine until their set temperature is reached and then open which can cause temperature fluctuations. Also adding some ice to the water will provide additional cooling capacity as ice requires additional energy to do the phase conversion from ice to water.
Rex
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Andy;
Most of the unlimited air racers at Reno use a "total loss" cooling system with a heat exchanger. The engine coolant is circulated through a tank filled with water and some methanol at atmospheric pressure. The pressurized engine coolant is hot enough to boil off the tank's contents, which are allowed to vent overboard. No radiator drag!
Regards, Neil Tucson, AZ
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Andy, did you make Speedweek this year? I was looking for you guys in my brief trip. This is a great thread, I am doing the rad in a tank as well. I copied Skips setup in his roadster in the build diaries.
http://www.landracing.com/forum/index.php/topic,6794.0.html
Did not make it to Speedweek this year, was a little burned out after last year, mentally, physically, and financially. Plus finishing our house remodel had been on hold for a few years making this happen. But slowly trying to work out my upgrade list that I have been pondering for a year.
Rex, thanks for the input. Currently I have two electric water pumps which are rated at 37 gal/min each, I don't have any pressure/flow info but in the realm of your suggestion. The one thing I still like about the radiator in a box scenario is the boil off "safety net" heat dissipation that you won't get from a simple closed system. The closed system may handle my current horsepower output but I am trying to accommodate future engine changes.
I'm working on layouts of a few possibilities given all the ideas suggested. Not necessarily the conventional "radiator in a box" but some differently packaged water to water heat exchangers.
More to come, thanks for all the suggestions.
Andy
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Good luck and keep us posted with your progress!
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Andy,
Good thinking about using a "real" water to water heat exchanger. If you know your heat load then the manufactures application engineering data and calculations can get the right size for you plus show you what the required fluid flows need to be to be efficient. Also "tube an shell" heat exchangers are typically fairly small and can be integrated into tight spaces in your car. Also look into the newer "plate" style exchangers as they are even smaller. Most of the "radiator in a box" coolers that you see at Bonneville have way to large of a radiator in them, a typical water to water exchanger is 7-10 times more efficient than an air to water radiator for equal surface area.
Regarding the "boil off" safety net, if you used a closed system with a water reservoir that can be pressurized then you can still have the protection of the additional energy required to phase change water to steam when it boils. But you need to be pressurized so it takes a strong container.
A little test that you might try is to use one of your electric pumps, I assume that you have one for each side of the flat motor, and have it pump through the engine and monitor the outlet pressure of the pump, this would be the pressure required to pump through the engine and you might even consider running the out let water into a 5 gallon bucket and time how long it take to fill which will then give you the actual flow rate through the engine. I'll bet you a beer it won't be 37 gpm.
Rex
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... As you can see from the pictures of Buddy's system and the system that Sum built for Hooley's Studi they are not small. When Hooley was running a supercharged small block Chevy they ran a pressurized closed system using a 15 or 20 gallon air bottle that carried the cooling water and that was on an engine that made at least 800-900 horse power. ...
Realizing that some people base their builds on what others have done (we have) I just wanted to clarify Rex's comments above. We did run the first year or two with a smaller tank that I think was about 16-18 gallons but then with the blown motor we ended up with the 30 gallon tank that we still use in the car. We also ran a 2-3 lb. radiator cap and circulated the water through the engine from the tank with a Meziere pump that I believe is about 25 gallons per minute and not their largest pump. The engine never had a heating problem except when we forgot to turn the pump on :cry:. I'd still like to put a second "on" switch on the the shift linkage just in case the driver forgot to turn the pumps on. Now we have to remember to turn the water pump and the intercooler pump on. Ran out of time to do this but might have time before World Finals.
We didn't like even the low pressure in the tank with the 2-3 lb. cap as the tank is in there with the driver. I feel much safer now that there is no pressure in that tank. Also cooling should be better with less chance of steam pockets in the motor with the 18 lb. cap we can now run with the rad-in-a-box.
Also like Rex said I'm sure we probably could run with a smaller radiator than what we have now, but if we get this motor up in the 1400-1600 HP range I'll feel better having it but also as he mentioned these radiators were designed in the first place as air to water coolers so more efficient water/water ones are probably out there. If money matters you can get a double pass like we are using for under $200 though.
I'm double passing the cooling water through the double pass radiator. If you just have the radiator in a box and aren't running water through it from another tank then I'm not sure you gain much with using a double pass radiator. Rex maybe you could comment on that.
For most of us that can't do all of the calculations and there are a lot of variables to consider maybe going oversize from the beginning if you have room is safer. That way you also have the potential to cover your butt if you do engine or power-added changes down the road,
Sum
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Sum I think that there still would be an advantage heat rises so the water going back would still be coolest available/
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Sum I think that there still would be an advantage heat rises so the water going back would still be coolest available/
I guess I see that in that the final pass through the radiator would be down in the cooler water. Makes sense and since the 2 pass are easy to obtain why not use one. They are even better with the same temp air going through the top and the bottom vs. a single pass in a more normal car use since the water in the rad sees the air twice,
Sum
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One advantage of a double pass radiator is that the water is higher velocity in the tubes as it is forced through 1/2 at a time.
Turbulent flow is your friend for heat exchange.
jon
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Here is my finished system. Double pass radiator and I use a pump/spray bar to circulate water inside the box. As yet untested in competition, so copy at your own risk :wink:
Skip Pipes
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What a great idea!! :-D
Here is my finished system. Double pass radiator and I use a pump/spray bar to circulate water inside the box. As yet untested in competition, so copy at your own risk :wink:
Skip Pipes
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Oh crap - busted again :-D
OK, my system is entirely based from what I spied off Dynoroom's car! Or a stolen design might be more accurate. Nonetheless, it's a really effective way to cool the engine.
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Oh crap - busted again :-D
OK, my system is entirely based from what I spied off Dynoroom's car! Or a stolen design might be more accurate. Nonetheless, it's a really effective way to cool the engine.
So who do I say I stole mine off of?! :-D :? :cheers:
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With this interest in the "radiator in a tank" cooling concept I still have one 15x15x4 double pass radiator left. See my add in the "For Sale" section, http://www.landracing.com/forum/index.php/topic,10946.0.html. In a properly designed system this radiator should be good for at least 800 - 1000 hp with a good circulation pump and a stout water pump. Price is $150 plus shipping. Radiator is pro built by Ron Davis.
Rex
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With this interest in the "radiator in a tank" cooling concept I still have one 15x15x4 double pass radiator left. See my add in the "For Sale" section, http://www.landracing.com/forum/index.php/topic,10946.0.html. In a properly designed system this radiator should be good for at least 800 - 1000 hp with a good circulation pump and a stout water pump. Price is $150 plus shipping. Radiator is pro built by Ron Davis.
Rex
With this interest in the "radiator in a tank" cooling concept I still have one 15x15x4 double pass radiator left. See my add in the "For Sale" section, http://www.landracing.com/forum/index.php/topic,10946.0.html. In a properly designed system this radiator should be good for at least 800 - 1000 hp with a good circulation pump and a stout water pump. Price is $150 plus shipping. Radiator is pro built by Ron Davis.
Rex
That is a good price. I'm wondering about how it flows.
(http://www.landracing.com/forum/index.php?action=dlattach;topic=10946.0;attach=31830;image)
Do the inlets/outlets have two possible connections...front or side? Does it come in at the middle one and flow up and across and then down and back out the the other one or is that where the tank fill is also? Can't tell from the picture and I"m confused as it looks like the side tank...
(http://www.landracing.com/forum/index.php?action=dlattach;topic=10946.0;attach=31828;image)
..is divided at two places (near side of the picture above)
Are the two protrusions to the left of the tank mounts or to an inside transmission cooler or something?
Thanks and hope you find a home for it as it could be a good tank for someone. Are you still building a lakester? I've been gone from here so have been out of the loop,
Sum
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These coolers, I had 3 at one time, were made for a Porsche race car and, as I understand, they mounted two of them in the front air damn area, and they were interconnected which explains the extra water connections. they are double pass, the connection that is toward the center is connected to the core on the right side. I think that the welds on the bottom of the tank are just welds to complete the tank and are not "dams" to prevent water flow. I have ran water through it to confirm the double pass configuration.
Regarding my lakester, Sum, I have started up again and I am doing some design to finalize the configuration of the final drive and also am planning to start building the buck for the body when I get back from the World Finals and a couple of weeks of hunting in Arizona next month. If I actually get some steam up on the build I will start a build thread.
Rex
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These coolers, I had 3 at one time, were made for a Porsche race car and, as I understand, they mounted two of them in the front air Dodge area, and they were interconnected which explains the extra water connections. they are double pass, the connection that is toward the center is connected to the core on the right side. I think that the welds on the bottom of the tank are just welds to complete the tank and are not "dams" to prevent water flow. I have ran water through it to confirm the double pass configuration.
Regarding my lakester, Sum, I have started up again and I am doing some design to finalize the configuration of the final drive and also am planning to start building the buck for the body when I get back from the World Finals and a couple of weeks of hunting in Arizona next month. If I actually get some steam up on the build I will start a build thread.
Rex
Thanks for the added info on the radiator and I'll be looking forward to the build pictures. Considering what you accomplished with your roadster they will be well worth viewing,
Sum
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The other recommendation that I would have is to use a BMW 320 I three way thermostat. These are really cheap, about $20, and what they allow you to do is to have full pump volume water flow through the engine while the engine is warming up as opposed to "normal" thermostats that "lock" the water in the engine until their set temperature is reached and then open which can cause temperature fluctuations. Also adding some ice to the water will provide additional cooling capacity as ice requires additional energy to do the phase conversion from ice to water.
Rex
Rex,
I've seen this recommended a few times and I've looked it up as far as what it looks like and it's original usage. I've never seen how someone has used it in an actual application though. Can anyone show a picture of the housing or mount they used with the above BMW thermostat?
Thanks,