Korndog said:
that looks sweet, but quick question, shouldn't the inlet to the air trap be long to be more effective? mines about that long, but my pump is soo strong, bubbles just get sucked back into the outlet.
When I designed my airtrap, the very simple idea was: air bubbles will rise, water will go down...
This is true for big bubbles but in fact it's not that simple.
Due to water velocity, as you observed yourself, most of the air will get sucked back into the outlet.
In real world conditions my airtrap turned out to work very well.
On special request I made five of them in total, bringing me to write a little
howto on my webpage.
I will try to explain the working with a little drawing:
As you probably observed too, after filling the loop, the trapped air in the coolant is "mulched" by the pump in thousants of little air bubbles.
It's more like foam and it's even more pronounced when using additives as Water Wetter, Purple Ice or other.
Coolant coming from the 1/2" ID tubing enters the Tee who has an ID of 20mm (a little more than 3/4"). Due to the increase of diameter the coolant slows down. Most of the flow goes indeed right to the outlet, but a part goes up to the upper reservoir of the airtrap where it creates a very slow vortex (I can only see this vortex with a torch lamp and when there is still air in the loop). This where the air is separated from the coolant by leaving enough time for the bubbles to reach the surface.
At every passage (several times per minute) through the airtrap a part of the coolant is made airfree.
From a milky solution at the beginning it turns to a clear liquid in tens of minutes, only leaving a layer of foam at the surface in the airtrap.
After a couple of hours this foam layer dissapears too and you will notice that the coolant level has dropped quite a bit.
Just add new coolant through the lid in the airtrap till level is halfway again.
During normal use, the lid of the airtrap must not be airtight (I open the lid about half a turn) to allow air bubbles to escape and air to enter if coolant level changes (ex. due to temperature variations).
Only during transportation or during filling the lid has to be closed completely.
Several commercial reservoirs-airtraps (like Innovatek's Tank-O-Matic or Fass-O-Matic) suffer from a big squirk: all the coolant passes through the reservoir making it almost useless with high flow pumps...but they are beauties. If I could find somebody with the needed knowledge and tools I liked to make my airtrap from anodized aluminium too...
CD