solar kiln started

[Tree Dan]

The Kiln looks great...feels good to have a load of wood in there cooking away 8)
125 Thats hot...whats your outside temp?

[Planman1954]

Ok...I have a suggestion for you. My friend told me the same thing after I mounted my fans. You could get some fiberglass insulation placed over some boards nailed to the bottom of the little 2x4s the fans are connected to, creating a mini attic. I think this will elevate the temperature and help the air to be more concentrated in their directional air flow downward. Check out my thread, and you'll see what I mean. I have some photos of it. Your circle of air is arbitrary like this, and creating the insulated attic will concentrate it more. It couldn't hurt!😀

[xlogger]

I had that on my list to do on the kiln. I saw where you did and I was going to copy that also. But I wanted to wait till I make sure the fans work. In case I had to go with different sizes later. I'm also going to  paint the bare wall that the fans are attached to you see black too, it does get quite a bit of sunlight on that side also. Thanks for all the help on the kiln.
The temp today was in the low 90's.

[GeneWengert-WoodDoc]

Keep in mind that the energy input to a solar kiln is determined by the size of the collector (the area of the shadow it makes at noon).  Once the energy has entered the kiln, you only need black absorber surfaces to convert it to heat...the geometry or location of the surfaces is not important.

Which way are the fans blowing?  Usually, if vents are on the rear wall, we want the air to move southward, down the collector and then through the lumber pile so the vents are the most efficient.

Very impressive kiln indeed.

[xlogger]

I'm pretty please with it so far but would like to get the temp up a little more. I have to fans blowing down the north wall. Maybe look and see about mounting the upwards just to see if it changes temps any. I do believe planman correct about boxing in the fans. I'm sure that would help with forcing more movement around the kiln.
I'll call this one the pineywoods-planman-xlogger design :D.

[GeneWengert-WoodDoc]

The PPX kiln would indeed benefit from have a baffle around the fans to avoid short circuiting the air and forcing the air through the pile.  However, under 20% MC, air flow speeds no longer affect drying speeds...we are waiting for the moisture to move to the surface of the wood (temperature and RH make this happen) and not waiting for the air to remove the moisture from the surface.