race radiators-single pass vs double pass vs triple pass ????????????????????????....
11-06-2007, 09:47 PM
#1
Le Mans Master
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race radiators-single pass vs double pass vs triple pass ????????????????????????....
Ok Guys!
I have been googling race radiators, holy smokes batman
tons of info
any preference on single pass radiators vs double or triple?
any creedence to the more water turbulence in double pass is cooler theory?
is this what road racing and Nascar guys run????
can stock water pump push water through a double pass good enough for it to work ?
I have been googling race radiators, holy smokes batman
tons of info
any preference on single pass radiators vs double or triple?
any creedence to the more water turbulence in double pass is cooler theory?
is this what road racing and Nascar guys run????
can stock water pump push water through a double pass good enough for it to work ?
11-06-2007, 11:07 PM
#2
Drifting
Member Since: Oct 2004
Location: Southwest Virginia
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DeWitt makes a great radiator. All welded dual row direct fit replacements. And the customer service is second to none!!!
http://www.dewitts.com/
http://www.dewitts.com/
11-06-2007, 11:20 PM
#3
Drifting
Rad sizing is something I know a little bit about; A double row rad will restrict coolant flow to a lesser degree (assuming that the tube diameters are constant), given that there are 2x as many tubes. And a 3x will flow coolant better yet.
The downside (there's always a caveat) is that the airside restriction goes up. That’s primarily a problem when you're sitting still, relying on the stock fans (sized for the stock airside restriction). If you don't daily drive it a lot, or spend most of your time at moderate or higher speeds the airside issues most likely won't matter.
Turbulence in a heat exchanger does help (laminar flow doesn't exchange heat as well) however, at the flow rates that radiators flow at the flow rates are sufficient in most cases to make the possibility of laminar flow rather small.
The bottom line; turbulence exists in the stock rad as well as any aftermarket rad. More turbulence in an aftermarket rad could help, but not to any significant degree. Mostly though you're benefiting from increased surface area with a 2x or 3x core...
The downside (there's always a caveat) is that the airside restriction goes up. That’s primarily a problem when you're sitting still, relying on the stock fans (sized for the stock airside restriction). If you don't daily drive it a lot, or spend most of your time at moderate or higher speeds the airside issues most likely won't matter.
Turbulence in a heat exchanger does help (laminar flow doesn't exchange heat as well) however, at the flow rates that radiators flow at the flow rates are sufficient in most cases to make the possibility of laminar flow rather small.
The bottom line; turbulence exists in the stock rad as well as any aftermarket rad. More turbulence in an aftermarket rad could help, but not to any significant degree. Mostly though you're benefiting from increased surface area with a 2x or 3x core...
11-06-2007, 11:45 PM
#4
Le Mans Master
Thread Starter
Member Since: Dec 2006
Location: Phoenix Arizona
Posts: 7,251
Likes: 0
Received 14 Likes
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14 Posts
Rad sizing is something I know a little bit about; A double row rad will restrict coolant flow to a lesser degree (assuming that the tube diameters are constant), given that there are 2x as many tubes. And a 3x will flow coolant better yet.
The downside (there's always a caveat) is that the airside restriction goes up. That’s primarily a problem when you're sitting still, relying on the stock fans (sized for the stock airside restriction). If you don't daily drive it a lot, or spend most of your time at moderate or higher speeds the airside issues most likely won't matter.
Turbulence in a heat exchanger does help (laminar flow doesn't exchange heat as well) however, at the flow rates that radiators flow at the flow rates are sufficient in most cases to make the possibility of laminar flow rather small.
The bottom line; turbulence exists in the stock rad as well as any aftermarket rad. More turbulence in an aftermarket rad could help, but not to any significant degree. Mostly though you're benefiting from increased surface area with a 2x or 3x core...
The downside (there's always a caveat) is that the airside restriction goes up. That’s primarily a problem when you're sitting still, relying on the stock fans (sized for the stock airside restriction). If you don't daily drive it a lot, or spend most of your time at moderate or higher speeds the airside issues most likely won't matter.
Turbulence in a heat exchanger does help (laminar flow doesn't exchange heat as well) however, at the flow rates that radiators flow at the flow rates are sufficient in most cases to make the possibility of laminar flow rather small.
The bottom line; turbulence exists in the stock rad as well as any aftermarket rad. More turbulence in an aftermarket rad could help, but not to any significant degree. Mostly though you're benefiting from increased surface area with a 2x or 3x core...
11-07-2007, 08:52 AM
#5
Safety Car
Looks like the NASCAR Cup cars use double pass ... see ....
http://www.crracing.com/radiators/nascar_nextel.shtml
http://www.crracing.com/radiators/nascar_nextel.shtml
11-07-2007, 12:03 PM
#6
Drifting
DeWitt makes a great radiator. All welded dual row direct fit replacements. And the customer service is second to none!!!
http://www.dewitts.com/
http://www.dewitts.com/
Check out his web site, a lot of info on how they are built. They are great radiators, I think the C6R team uses them 
11-07-2007, 12:18 PM
#7
Safety Car
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HowWhyWhyHow (05-23-2022)
11-07-2007, 12:42 PM
#8
Race Director
Also, consider a RON DAVIS aluminum radiator. He's been supplying coolant radiators and heat exchangers for many forms of racing for years.
11-09-2007, 06:37 PM
#9
Former Vendor
11-09-2007, 07:09 PM
#10
Former Vendor
The term "double pass" or "triple pass" is widely misunderstood. Most people think that somehow fluid passes thu the radiator more than once and that simply isn't true.
A better term for this design would be "single baffle" or "double baffle" because that's all it is. The typical radiator has no internal baffles and all the flow goes into one end tank and comes out the other. The flow direction in the core is "one way", typically right to left. But when you add an internal baffle inside the inlet tank (about half way down) it forces the fluid to go one direction for the first half of the core and then back the other way for the bottom half. This single baffle (or twopass) cuts the core in half and runs them in series. This doubles the flow speed rate and the pressure drop through the core. A single baffle core will have the inlet and outlet connections on the same end tank.
A double baffle (triplepass) cuts the core into three separate, smaller coes, and the flow thru the core makes an S pattern. Again, even higher flow rates and higher pressure drops. I see it as basically a gimick to sell radiators.
Here's a graphic for help
A better term for this design would be "single baffle" or "double baffle" because that's all it is. The typical radiator has no internal baffles and all the flow goes into one end tank and comes out the other. The flow direction in the core is "one way", typically right to left. But when you add an internal baffle inside the inlet tank (about half way down) it forces the fluid to go one direction for the first half of the core and then back the other way for the bottom half. This single baffle (or twopass) cuts the core in half and runs them in series. This doubles the flow speed rate and the pressure drop through the core. A single baffle core will have the inlet and outlet connections on the same end tank.
A double baffle (triplepass) cuts the core into three separate, smaller coes, and the flow thru the core makes an S pattern. Again, even higher flow rates and higher pressure drops. I see it as basically a gimick to sell radiators.
Here's a graphic for help
