xuv-this
bondo afficianado
- Location
- southwest VA.
yeah, i know not another radiator thread, blah, blah. ok, so i think i've read every single radiator option post on naxja tonight, and was thinking of going with a 3 core radiator, and then it hit me like a brick.
the problem in our radiator design is flow resistance. period. the friggin' thing is 3 times as long as it is tall. all i can say to the 3 row fans is that i would not want to be you in 50,000 miles. a normally shaped radiator is like that for a reason. yes, a 3 row for us would initally flow and transfer heat better than a stock unit until the normal corrosion/junk starts building up, only the resistance affects our radiator shape more. the xj radiator has less flow volume than say a tj, so the cooling system has to make up for it in speed.
i saw a random post where some person was comparing the copper in radiators to the copper in electrical wiring, and then it hit me. resistance. most radiators have like 50 row tubes 15" long, but we have 25 row tubes 30" long. now if you do the math, that's pretty much the same surface area. yeah. apply that to 12 volts in a wire if you're working on say a custom dual battery system or mabye buying an amp kit to drive your sub. and forget about the voltage drop in your wire size. simply put, resistance. my point is that our radiator design, because of the longer tubes, get flow affected more by the resistance to the flow in the tubes. see, in a 2 parallel wires 1 foot long, or 1 wire 2 feet long of the same gauge, theoretically they would have the same total resistance. but they don't. the resistance compounds itself over the wires length. the resistance % is the same, but as the wire goes on and on, the same coefficient would be applied to that wire say 10 feet down, it gets applied to less voltage.
the same principle can be applied the resistance of the radiator on the cooling system flow. why do you think the engineers put the electric fan on the cold side of the radiator? of course a nice shiny radiator has given so many of you guys an improvement in cooling. it hasn't gunked up yet. the problem in adding surface area to that design of radiator is that there's not much space to do it. the tubes are just made smaller. so there is more inner surface area in roughly the same space, which doesn't do much for flow. as far as copper vs aluminum, those tiny copper tubes can get pretty nasty after a while. nice clean new aluminum probably would have a better thermal conductivity.
ok, i'm beat. so i guess i'm done Hasta .
the problem in our radiator design is flow resistance. period. the friggin' thing is 3 times as long as it is tall. all i can say to the 3 row fans is that i would not want to be you in 50,000 miles. a normally shaped radiator is like that for a reason. yes, a 3 row for us would initally flow and transfer heat better than a stock unit until the normal corrosion/junk starts building up, only the resistance affects our radiator shape more. the xj radiator has less flow volume than say a tj, so the cooling system has to make up for it in speed.
i saw a random post where some person was comparing the copper in radiators to the copper in electrical wiring, and then it hit me. resistance. most radiators have like 50 row tubes 15" long, but we have 25 row tubes 30" long. now if you do the math, that's pretty much the same surface area. yeah. apply that to 12 volts in a wire if you're working on say a custom dual battery system or mabye buying an amp kit to drive your sub. and forget about the voltage drop in your wire size. simply put, resistance. my point is that our radiator design, because of the longer tubes, get flow affected more by the resistance to the flow in the tubes. see, in a 2 parallel wires 1 foot long, or 1 wire 2 feet long of the same gauge, theoretically they would have the same total resistance. but they don't. the resistance compounds itself over the wires length. the resistance % is the same, but as the wire goes on and on, the same coefficient would be applied to that wire say 10 feet down, it gets applied to less voltage.
the same principle can be applied the resistance of the radiator on the cooling system flow. why do you think the engineers put the electric fan on the cold side of the radiator? of course a nice shiny radiator has given so many of you guys an improvement in cooling. it hasn't gunked up yet. the problem in adding surface area to that design of radiator is that there's not much space to do it. the tubes are just made smaller. so there is more inner surface area in roughly the same space, which doesn't do much for flow. as far as copper vs aluminum, those tiny copper tubes can get pretty nasty after a while. nice clean new aluminum probably would have a better thermal conductivity.
ok, i'm beat. so i guess i'm done Hasta .
