Mark Log
Tuesday, October 18, 2016
No internet at work but was able to work on FreeCAD designs. FreeCAD seems extremely tedious and cumbersome to use, but it's also the only non-electrical-focused CAD software I've ever used, so I really can't say. Completed detailed layout of the individual TEG modules on the steel 2x6x30in pipe. Not sure how to share file at the moment, but will add screen capture to Google Slides presentation.
Calculated volume of insulating material needed to fill the 4mm tall spaces in between the individual TEG modules to insulate the cold water and hot water pipes from each other everywhere that a TEG module doesn't connect them. (152.4×762×4-40×40×24)×4 = 1.7044608 × 10^6 mm^3 per pair of sandwiched pipes. So multiply by four junctions to get 6.8178432 × 10^6 mm^3 or about 230.5387 fl oz or about 1.8 gallons. That estimate seems high.
Sunday, October 16, 2016
Rough Google slides presentation up. Included sketches of basic TEG layouts with calculations on spacial arrangements. Compiled various design notes from Marcin and others. Researched products to be used, included links. Need to finalize those asap. Read through Marcin's Google Slides presentation on the hydronic stove: http://opensourceecology.org/wiki/Open_Source_Hydronic_Wood_Stove
Also looked at this on the heat exchanger: http://opensourceecology.org/wiki/Wood_Stove_with_Heat_Exchanger
"The pellet burner fires a stove which can also run on regular wood. The flame heats up a heat exchanger which produces the hot water or water mix for the teg. The hydronic heating Loop will be a separate heat exchanger inside the same stove which then feeds the water to the floor. The teg is independent of the hydronic water heating at first. However the teg has a cold water line running from the aquaponic ponds to provide the cooling water. That water is pumped while the hot water from the stove Rises through the TEG by convection." -Marcin
Fri Oct 14, 2016
MJ notes - let's get the temperature difference up to 100C with glycol or sugar water.
Thursday, October 13, 2016
Been out of town. Did basic Google and YouTube searches for existing implementations of TEG systems, DIY-ers, and TEG knowledge. Reviewed existing material from wiki on TEG. Reviewed Marcin's log of feedback from ITS board outreach. Learned how to create wiki account and create a work log. Plan to have basic first drafts of designs up tomorrow (later today). "...TEG's fill factor is ~50%, meaning cover 50% surface area of the hot tube... And because only 1/2 of the 60C drop is applied on TEG..." Follow up on these comments from Zhixi... Sounds like we need a different design or 5x bigger system to achieve 100W?