Four solar cooker Ulog. Construction and performance

[Christophe]

Construction monitoring and perfomances (improvements?) Of a Ulog type solar cooker oven with double glazing recovery window (direct recycling).

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DAY 1: all first tests



a) 1 frame double glazing recovery, glass surface 63 * 40 therefore equivalent to an 50 * 50 cm (minimum size recommended in the book)
b) glued synthetic mirror
c) Gardening pan for the 1er tests (it already heats up quite well without any insulation, I made IR thermometer measurements on the 2 pieces of slate between 70 and 75 ° C after 1h)

The synthetic mirror, reflects wonderfully:



By cons I do not know how long it will hold ... we'll be fine. I had paid twenty euros in a brico for 100 * 50 cm.

Advantage is that it is lighter and unbreakable! Before I put the cord, the wind dropped the mirror, with a glass mirror, I do not know if it would still be intact ...

DAY 2: the raw chassis



"Bare" chassis



I triangulated to make it the most resistant possible compared to the weight (the chassis is its weight and everything will be handled frequently ...)

Position "winter" reflector at the bottom:



"Winter" position in normal mode:



Setting up of the glazing + reflector on the chassis (game = 1 mm!), I would leave it removable to facilitate its displacement.



This chassis will easily put a 2ieme reflector from the bottom and will increase the power of interest (about 30% priori). We can imagine putting on the sides also ... if really the T ° is not enough!

Remains to be done:

a) the oven bowl (the most delicate I think)
b) the outside walls
c) insulation

[seb1000]

pretty !!

you're faster than me.

where did you find your IR thermometer, and how much did you pay for it if it was not indiscreet?
what is the point of having a mirror position at the bottom?

[Christophe]

Thank you

It is not indiscreet, quite the contrary, I found it not very far: https://www.econologie.com/shop/thermome ... p-132.html

Another model that makes IR too: https://www.econologie.com/shop/thermome ... p-326.html

The mirror down if there is one, there is no interest (better one at the top, although when the sun is at the zenith, down it must work well ...) mirror + low = increase the oven power (especially in summer), as you put on the sides for your test.

If the 1st cooking tests are ok, I will see to put another reflector (I still have some survival blankets to "recycle")

[Christophe]

3 day (small day):

Recovery of the tank material: aluminum sheet and start of cutting:



Hello the final puzzle!



I think to fold and rivet everything.

Technical question: Is the aluminum recommended in Ulog furnaces? Can I use a steel tank? (I still read nothing about it in the book I have on the cookers)

Because it is easier to recover black lacquered steel (all classic ovens) than aluminum! Or is it simply a question of ease of realization: the aluminum folds much more easily than steel obviously (and weight?) ???

[Christophe]

Here is the "puzzle" tank (don't laugh) almost finished, a little cleaning and straightening and it should do it.



I did not have enough material to do the bottom, or it would be superimposed bands ... bof ... I think so make the bottom in lacquered steel sheet.

If not also stainless steel washing machine drums to recycle but I think keep them to make concentrator.

[seb1000]

it goes on your side, well!

I'm questioning my parabolic mirror and I'm hoping soon.

continue to show us your progress ;-)

[Christophe]

Ah yes, this subject is made for that.

I did not understand what you are questioning ???

[seb1000]

I question the shape of my "parabolic mirror" (which does not bear its name so well) which will be placed under the solar oven.

I test the cutting and the reflection of the light rays on this mirror according to the inclination of the sun and the mirror: I check that the rays converge well (or approximately) where I want.

and that's it I got the confirmation of my idea.

remains a parameter to manage: the parameter a from the equation of my parable: y = ax² I took a = 0,714, but maybe it will have to be reduced a bit.

[hic]

Construction monitoring and perfomances (improvements?) Of a Ulog type solar cooker oven with double glazing recovery window (direct recycling). . Php

DAY 1: all first tests
Remains to be done:

a) the oven bowl (the most delicate I think)
b) the outside walls
c) insulation

hi Christophe

It would be more effective
to put your tiles standing in the diagonal of a cone / mirror at 90 °,

For direct radiation, there is clearly "concentration"
towards the center, on the tiles


*** a cone is also an indirect radiation trap !!!!!! ***

this cone traps any radiation that arrive in an angle of 85 °
in this case, it will be less "concentrative"
but much better than a simple tank

and equivalent to
if the dish is shaped like a 'very closed' bowl
we will have the same result
that the cone or the tank, or almost for the diffused light or sun in diagonal as the parable approaches the 90 °


you could also test a double parable,
of the type that we meet in certain solar thermal

[Christophe]

Hi Hic,

For the tiles, let it down was just for the 1er test day!

For the cone oven, you have to see the side of a DATS: https://www.econologie.com/forums/four-solai ... 10766.html

For the ULOG, I will put, I think an 2ieme mirror opposite the 2ieme. I already have to finish the tank there!