Josiah Kobernik wrote:I calculated that the total weight of the roof with three feet of soil soaking wet above the membrane is 12,660 lbs.
Each of the 8, 8 inch posts can support more than 22,000 lbs. So that's cool.
Josiah Kobernik wrote:here are the drawings that will be the basis for Kyle's new 3D model.
Josiah Kobernik wrote:In critique of the strategy of capping things off for later testing, I will relay two things that Paul has told me.
thing one, instead of testing each innovation independently with controls, paul likes to heap ten or more innovations into one experiment and then if the experiment is successful, you can successively divide the innovations in half to sort for relative influence.
thing two, the annualized thermal inertia aspect of wofati structures takes years to test. It may take 2 or more years for the mass to be fully charged and operating in semi-stable seasonal temperature fluctuations. So capping and uncapping earth tubes within the first 5 years muddies the results of the thermal inertia. That being said, If it takes several years for the greenhouse to start working, then it's not very attractive as a design solution.
Josiah Kobernik wrote:I think a thesis is a good idea. here is my first crack at it.
"A combination of:
An 8 foot deep cold sink
Two well casings extending 19 feet deep below the cold sink fitted with passive air circulation units
Dry earth thermal mass on the roof, as well as the North, East, and West walls that is disconnected from surrounding soil by a polyethylene membrane “umbrella”
Inflow of household greywater at or above room temperature
A south facing glass wall measuring 10 feet by 5.5 feet, sloped perpendicular to the angle of the sun at solar noon on February 1st
Will be sufficient to keep a greenhouse with interior dimensions of 10 feet by 9.5 feet above 50 degrees and below 92 degrees year-round in Western Montana at an elevation of 3200 feet above sea level."
David Haight wrote:
Josiah Kobernik wrote:
What if the "fog harp" was actually made of angled heat pipes stuck into the rear mass(?)
David, I woke up thinking about heat pipes this morning. I was trying to figure out how heat pipes from the mass could cool the fog harp, but I think you nailed it by having the heat pipe itself be the condensing surface.
Anyone have design ideas for DIY heat pipes that are filled with non toxic material?
Earlier in the thread, Greg mentioned using water. Do you think that would suffice in this scenario?
Any working fluid can be tweaked to the right temperature range by getting the internal pressure right. For water, this means pulling a vacuum to get the pressure way way way down so that the water is boiling at room temp. Means either pulling the vacuum as you seal it up, or having a service port were the the vacuum can be pulled after sealing the pipe and re-pulled as leakage occurs. Ammonia and propane are two other possible working fluids but as someone else mentioned the toxicity potential, especially in a closed environment, might be a no go. Ethanol and Methanol might also work, I'll have to consult my reference to see if they will work with copper or aluminum pipe material...