Those with turbulators

[laynes69]

I don't have a boiler, but do have a wood furnace with a secondary heat exchanger that has 3 large tubes to collect heat from. I recently was reading on here and discovered that turbulators help to break up the "core" of the heat in the exchanger tubes. We have 2 tubes that are roughly 3.5" in diameter and a large 6" tube that runs down the center of the top of the furnace. We see very little buildup and I could place them and remove them in seconds. Can they be used to increase heat transfer on a forced air furnace? I see they are used on boilers, but I wasn't sure about any other installation. This is something that interests me. We have excellent draft so slowing down some won't be an issue. Thoughts?

 

[laynes69]

Here is a couple of photos to show the exchanger.

 

[pybyr]

Google laminar flow vs turbulent flow-- the turbulators not only increase the time the hot gas spends in the HX, it also increases, dramatically, the extent to which the hottest parts of the flow contact the walls of the HX.

If I had a situation like yours, I'd definitely try some experiments with strips of sheetmetal formed like spiral noodles...

good luck and let us know what you try and what you find.

 

[in hot water]

I don't think I would modify the appliance without the manufacturers approval. If you are talking about a wood fired forced air furnace, If you get a crack in the HX you have the potential to get CO carbon monoxide in the air stream to the building. In a boiler you get a water leak on the floor.

Keep your and your families safety in mind when playing with combustion and byproducts of. A low level CO detector should be required with all wood fueled furnaces. Any fueled appliance in a living space, actually.

hr

 

[mikeyny]

With a boiler there is water on the other side of the heat exchange tubes and the temps on the water side range from 100 to 240 degrees. With air it may get too hot if you slow down the passage of exhaust gas and warp or crack the tubes, which could cause a dangerous situation. On a boiler if one of the heat exchange tubes did crack water would flow into the fire chamber putting out the fire but with hot air the fire would enter the heating air side and possibly burn up the house. Be very safe no mater what you do. research a little more into what the manufacturer suggests and follow those guidelines closely.

Mike