Alright, after standing at my work bench for a while and worrying over all the details that I did not have answers to, I decided to just get started and see where it takes me.
I started by deciding I was going to test the firebrick nozzle idea, and maybe eventually wedge a tungsten wedding band in there and see if that makes any difference. I did not want any air leaks, so I thought I would weld a threaded pipe section to the bottom of my very thin pail… It sounded like a fun challenge, but it wasnt. I did grind the threaded pipe down to a very narrow edge, and very carefully added some steel to the edge of the hole, but it was not ideal. After filling over some burn-throughs I went back and covered it all with some bronze braze to seal all the pinholes. Got it on there, and I think it is pretty well sealed. I think the bronze braze starts to lose strength at about 500 F, but since the welds should hold it in place It shouldnt fail until it reaches more like 1000F. I am hoping it will never get that hot.
I also put together a little stand so that If this pail doesnt pan out I can swap it for another one. I threaded on a T just to get a sense for how much space I need below, but I was wondering, how far can you “reach” with a propane torch for lighting? I was thinking that I would light from the bottom, and plumb in the EGR to the side of the T.
I set up a filter in an ammo can, and it has much thicker walls, so it was easier to work on. I made a wire cage for a wool sock filter, and put the outlet at the opposite corner. I sewed up a little bag that slips on to the cage, and which I will secure with a hose clamp. I got some wool batts for the filter media, and will put a cloth over top of it all.
the smallest ceramic hole saw I had was 3/4 so that is what I will start with for my nozzle. My plan is to bed the brick down in a little refractory cement, then fill the areas around the edges with ashes to keep any air from leaking around the bottom of the brick.
I also made an outlet pipe at the top that will suck the gas from just under the lid. This one I brazed on, and that was Much easier. I figure since the top of the reactor should not be getting too hot, brazing should be fine. I am using a heavy PVC spa hose for my tubing, which with a 1" ID fits well onto 1" OD thin walled tube. It will get hose clamped on once everything is up and running. The reactor lid came with a clamp, but I am a little leery of using it on account of the risk of a backfire. I am thinking I might secure it with a handful of those little document clips - and maybe devise some spring-loaded setup later. maybe connect it down to the stand somehow.
I have ordered a thermometer and an 800C thermocouple probe that I will thread in to the side of the reactor part way up the side to get a relative temperature reading of the reaction, and I will probably put another probe on the outlet pipe.
So, a couple questions:
I want to eventually put a cyclone right on to my outlet pipe - can anyone point me towards the dimensions (diameter, height, taper, etc) I would want to use for a 1" inlet?
I looked at the muffler on the donor engine, and it does not have threads, but bolts on. Could I drill a hole in it for the EGR, or weld a pipe over part of the outlet, or do i need to fabricate some sort of manifold?
I am going to work on my blower next, and see if I can get this thing to flare.