Aslan Core Gets a Mass (Image Heavy)

Oh, I also added a "Magic Heat Reclaimer" to extract more heat, which it does, though I want to put a bigger blower on it to give it more power.

That is amazing. It reminds me of the scene in Despicable Me where Gru plays a carnival game. The attendant insists that the UFO wasn't knocked over by the girl's ping pong ball. So Gru decides to take a turn. He whips out his massive gun, brews up a ball of flaming lava, and shoots it at the UFO. When the UFO disintegrates, he calls out, "Knocked Over!"

You have knocked over that core.



Was it a five minute riser on top of a ceramic fiberboard core?

Jeremy VanGelder wrote:You have knocked over that core.


Was it a five minute riser on top of a ceramic fiberboard core?

The amazing part is that it's melted and still works. I mean, I had to cram a bunch of fire bricks and some chunks of CFB in it to constrict it down, but it's still working today.

No, it wasn't a five minute riser, it was a ceramic fiber riser sleeve, 2" wall thickness, 8" (nominal 7.5" actual) internal diameter, two 24" sections stacked on the top of the core.

I do wonder what happens when a 5MR melts down.

If I were to do it again, I would line the bottom and sides, at least with fire brick. This burn tunnel of the core was 3" too tall, which was fine on lower BTU fuel, and when it was full of ash, but the ceramic fiber was rapidly abraded inside the burn tunnel during ash removal, most of which was by shop-vac. I would have reduced that height to a consistent 8" nominal cross section, and lined any parts that could be touched with brick. I would also have used a brick feed chute, rather than steel. As predicted, it warped badly and had to be ground on and bent back into place periodically. However, it did work. I would also capture the entire core in masonry rather than let the manifold section be open, just so the masonry couldn't warp out of place.

Other than the issues above, I was very happy with this system, and it performed admirably. It is very easy to start, being a very wide open system. It was a great first system. Good for learning and also heating. No smokeback issues, never any issue with draft.

Solomon,

Thank you so much for all the extended documentation. I'm still early in planning my first rocket, and your experience is extremely helpful.

The 2x4 house I'll be heating is similar to yours in size. I'd like to make sure I understand your wood usage experience. If I understand correctly, using your 7.5" J-channel rocket you have heated your house in Oregon with about 1/6 cord every 10 days... or a cord ~ every 2 months... maybe 2+ cords per winter? That would be very encouraging to me.

Sorry to hear about your riser melt. I'm planning a DSR3, partly because that design seems resistant to runaway.

In case you haven't seen it before, thought you might find this resource helpful. It suggests that your "melt" is actually an accelerating process that may ultimately crumble your riser if unchecked... which could be bad  https://donkey32.proboards.com/thread/3909/firebricks-refractories-fail-silica-flux  

Best wishes,

Craig