eBIAB with passive recurculation

Can't sleep so I'm up testing an idea.

eBIAB kettle with a solid false bottom (upside down pie tin?) with a riser tube off to the side that stops at or just below the surface of the mash/wort. Much like an old perculator coffee pot but not needing to raise fluid above the surface.

Would there be enough circulation to even out the temps. I know it won't be as much as with a pump but how much is needed?

Possibly some kind of passive in kettle RIMs. A tube over the element with a riser at one end should increase flow.

Click for pic.

Edit: added pic

Sounds interesting... is the water just going to seep into the bottom portion? I think the convection on the hot water lends itself to doing this on it's own without any funneling needed (some specialist will probably correct me on that). I mean you can test it, but, that's my hypothesis and I'm sticking with it

If the element was sticking straight up (in the middle like some pro systems) and was enclosed except for top and bottom areas you might see a better utilization of the natural convection process.

I've thought about the vertical element but the small batch size (3.5g) & grain bag make it difficult. In my 12"dia. 20qt kettle w/ a 7.5" element it would need 3.67g just to cover the element. The bag wouldn't be so bad, normal bag with a "sock" in the center to go over a cut down Sanke spear(?) covering the element. The center outlet for the riser should be good, I'm thinking the hot wort would spread fairly evenly across the top of the mash.

May have to try this later but right now another kettle is not on the buy list.

Last nights experiment was promising. With my collector covering only 11% of the heated area i could see a dome in the surface of the water above the riser. To check the flow I dropped a pinch of black pepper over the riser & in a couple seconds it spread to the edge of the kettle. I tried again away from the riser & it spread to about 2in dia. Thinking it might be a surface tension thing I tried again in a bowl of water & again it spread to about 2in dia.

At this point I'm planing to make the version in the drawing & work out the details as I find them.

Still hoping for more input on this.

My money is on no. There isn't a big enough temp difference between the top and bottom of your pot.