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bondo |
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Practicing my perpendicular parking ![]() ![]() ![]() ![]() Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California ![]() |
Hopefully I can get some input on this without too much of the inevitable "that won't work" (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif)
I'm cutting down a large tall radiator into a shorter one.. 1/3 the height to be exact. The 3 layers of radiator will be set up in a cross flow, sequentially. The hottest water will enter the rearmost later, travel across, then across again in the middle layer, and across yet again in the front layer. The idea is the hottest water gets the hottest air, and the coldest water gets the coldest air. This way delta T stays pretty constant.. I'm thinking of it as trying to heat the air as much as possible, which would cool the water as much as possible. So I realize that cooling capacity will be reduced, as I will be dealing with 1/3 as much air. But then the cooling capacity must be more than 1/3, because it's 3 layers thick instead of 1. My question is what percentage of the original cooling capacity should I be expecting? Would it do me any good to do 5 layers instead of 3? (by adding 2/3 of a second radiator) The original radiator cooled the same engine just fine, in a heavier car, with an AC condenser preheating the air. I will be running an electric pump, so I will have an advantage at idle. |
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SLITS |
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"This Utah shit is HARSH!" ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None ![]() ![]() |
Rate of water flow thru a radiator is very important. On our water cooled race cars we used a 4 row crossflow aluminum radiator. To slow the water down, we used blanking sleeves in place of a thermostat. The one we ran was a plate with a 1/4" hole in it.
We also experimented with different ratio pulleys to slow the water pump speed down and found this to be the best solution. That said, we were operating within a specific RPM range on the track (5500 to 8500 RPM). The only time the engine RPM was below 5500 was in the paddock. I am not a thermodynamic engineer, nor a true HVAC person (spent a lot of time in that industry though). I have never seen heat exchangers plumbed in series...especially a fluid to air heat transfer. I do know that the effeciency is a relationship between the rate of fluid flow, material of heat exchanger construction and the surface area of the fins attached to the liquib bearing tube....break the bond between the fins/tube and effeciency immediately starts dropping radically. Oh well, it's to early to make any sense |
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