First idea was to use this Car radiator, but I wanted a TOTAL noise free system,
so a ZERO fan system was made, using a BIG homemade radiator.
Here is one of my radiators from an old Ford, it has 20 copper tubes inside that is 8mm diameter
The cooling area is about 175 x 190 mm, and it holds about 200 ml of water inside.
See the water hose connection is about 16 mm outside, you can almost see the cooling copper tube inside the hole.
Here is my homemade brass converter so I can fit 1/2" hose to my readiator
17mm diameter and 13.5 mm with 9.7mm hole, it was easy to make using a turning lathe
Car radiator performance test setup: total water in this setup = 3.5 Liters and the flow is 4.2L/M.
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The fan is a HUGE Papst 24 Volt type, but it starts fine at 4.5 volts.
When I start I just pour in fresh hot water until I have a water temperature of 54C
then I wait one minute before the fan is started and check that the temp is still 54C.
Now, how long time will it take to cool down 3.5 Liter water using this type of radiator and fan,
using different fan voltage = speed = noise ok got the point ?
The room temperature was about 20 C, at 5,6,7 volts the fan noise is really low.
at 8 to 12 V it is moderate, but at 24 V it is super powerfull !! and makes really much noice, it will blow out a candle over 1 meter away.
Next day I tested another radiator exactly same size from same car model, but this one uses 20 round tubes to carry water,
this one I call model B with round water tubes and model A with flat tubes for water.
model A: 4.17 l/m flow, so it has a bit more resistance to the water flow.
model B: 4.6 l/m flow, so it is not loading the water flow so much.
OK how well does they perform, See the results above for model A, it takes 5.30 to cool 3.5 Liter down 20C
but it takes only 5.19 for model B, After a closer inspection I found out that this model B has closer and more fine cooling plates,
this means it has better contact with the air that is pressed though it.
It also have more resistance to the air flow, this is measured on sound level at same voltage,
due to a higher loading the fan will turn slower at same voltage and generate less noise, this is useable,
but not to me :-) something more silent was made !! with my ZERO fan radiator.
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