This is what pyrolized fuel looks like and identified the pyrolysis zone in my gasifier. An important location to know for advanced refinements in design. One thing I have to remember is that the present pyrolysis zone (location defined by temperature) was located by an under pulling engine. Using a larger engine (the one the gasifier was designed for) will give me hotter oxidation zone temps and the pyrolysis zone will move upward in the burner (fire) tube. Remember this before you do something exotic, design wise. What you want to pull off may be in a different location than previously observed.
This one will tell me the temp of the preheated air entering the single port air inlet manifold. Probably should be insulated so these are about temps but good enough for trends.
NEW. This is the temp of the hot gas exiting the burner shell and flowing into the side of the cyclone inside the preheat shroud. Again, could be insulated. The poly was used to cover the connection while the caulk cured. I should have removed it for the debut, lol.
This is the temperature of the gas exiting the top of the cyclone and headed for the cooling tubes (radiator). This will give me sense of the temp drop through the cyclone. If this temp gets too low some condensation may occur in the cyclone.
I can use the lighting port to insert a temp prob into the oxidation zone. This is the temp I am most interested in.
Yes, everything got a new coat of paint all the same shade and sheen, lol.
Hey Everyone,
I used to wrap the vacuum cleaner tube with duct tape to get an airtight fit, then wrestle with it a bit to switch from flare (no filter) mode to run mode with filter. Here’s a better and quicker connect/disconnect method. This is just a method, your sizes may vary. A flaring method will be incorporated into the final engine feed design.
Glue the 1 1/2" coupling to the 1 1/2" stub on the exit side of the filter shutoff. Glue in the 1 1’2" x 1 1/4" reducing bushing and lastly glue in the 1 1/4" pvc pipe containing the vac piece.
. When you are satisfied with the flare, switch to the run set up. ALWAYS shut off the vacuum first, then the flare valve. This will eliminate the point of ignition from the swirl burner. Pull hose from swirl burner and lay on ground. Quickly switch the hose from the flare outlet to the filter outlet and immediately open the filter valve and turn on the vacuum. MOST IMPORTANT: let the gas run for several minutes +/- to flush the oxygen from the filter unit and lines. Caution here, if in doubt let the gas go longer before using it. The filter could be a bomb.
Move vacuum closer so you can shut it off from the pallet. Do this first. Then shut off the flare valve, step down disconnect the swirl burner tube (notice the old duct tape sealing method) and step back up move vacuum line to filter and open the filter valve. If it takes you 10 secs, you’re too slow. Reconnect hose to swirl burner ( turn on fan) or engine, continue burn. If connecting to an engine you bypass the vacuum (it’s now provided by the engine).
The weather is supposed to be nice tomorrow, so I’m going to burn some measured amounts of wood, take some data and video and report back. My friend and neighbor, Bill, is coming over to watch the firing, it should be fun.
Pepe
Hmmmm I’ve always shut the vac off first then closed the valve… I found that that the vac would try to go into jet engine mode momentarily if done the other way.
Hey Everyone,
This is my new fan project. I like the motor/rotor separation, no mixing here, hopefully.
Gordon Ooghe, from post 275, I’ll have more info for you soon.
I rolled a cone to transition from 2" pipe to the 5 1/4" fan inlet. I used eighteen 20 degree bends. This type of inlet is one of those efficiency tweeks. It’s not totally to the spec 7 degree slope, it would be longer so I compromised a bit.
I’ll leave this til tomorrow am before I drill the mounting holes. I will drill graduated holes to eliminate cracking the flange by taking too big a bite. I hope this holds up to the test of time.
Pepe
Well, it’s tomorrow and here’s the finished fan ready to fit into the system. At this point in the beta version, it may be a stand alone unit. My bigger picture is a little more compact unified arrangement and I will fabricate a metal adapter for the outlet just to be safe from accidentally breaking the pvc… It’ll fill my winter hours in the shop.
I ended up splitting the housing and putting high temp grease on all the mating surfaces. I had some slight smoke leaks before I did this.
Hi Stephen,
Thanks for the comment. What I really need is a plasma cutter, slip roller, etc, etc, etc as Arvid said.
May I ask how you transitioned the intake? Any clearance issues like I had. The fan has relatively close tolerances.
Pepe
A closer look showed why the unit kept running like there was no bridge. The fuel you see in the firetube fell from underneath the bridge and the hearth was fed and continued a good gas producing burn as seen in the last seconds of the vid. I like the gas color. I estimate I would only have had another 20 or so minutes of run time before the fuel was 4" above the nozzles. Much, much longer had the bridge collapsed.
One tap from a stick and the whole bridge collapsed just as you see it. Odd, too in that I ran the vibrator several times during the run. It’s now ready to start over with a new char bed established. I’ll just top off the hopper . I think I will move/rearrange the vibrator mechanism more to the hopper side.
Ambient temperature 65 degrees.
Here are the operating times and temps throughout the burn. I hope they’re dark enough to read.
All in all it was a good burn. The temps were slow to peak which I attribute to the fan being under powered for my particular sizing of gasifier. It certainly works well though as a good starter fan. The scrapping racket you hear from the fan on startup happens when I push on the motor or switch housing. It moves the blade closer to the housing and the tops of the mounting rivets. Just be careful.
Here are a short and long version of some flare action
.
short http://youtu.be/BqnjOxSNEvI
Your system and fuels will for sure be different than our systems. But when I set up our vibratro timer is usually off for only 10 to 15 seconds this is with the very light cedar. The on time is very short just a few seconds. I always start out with a close timed interval, this causes a rich condition and then back of the off intervals until I have a satisfactory flare. The Vibrator is as close to the top of the hopper as possible and in our case is very effective and touchy it does not take much. We want the machine to do some bridging to get the results you just experience. We try to get the shaker to shake down just enough to keep the hearth flowing and hot.
Hi Matt,
Thanks for the response. So your vibrator comes on approx every 15 secs for a couple of secs. This means you continuously run the vibrator thru the burn. Yes, our fuels have a lot to say about this. I haven’t timered mine yet, but I previously ran it manually 15 secs every 10-15 mins. I didn’t this time, only 2-3 at most for the hr+ run. Time to install that timer!
My vibrator will move, also.
Pepe
Hi All,
I finally got the flanges and bracket cut out and welded onto my hopper.
I welded one flange to the hopper using the hopper weld seam as a thicker base, shortened the original hanging bracket and bolted it together. I ran some beads on the pulley weight to increase the shake power. This certainly does shake the hopper now.
Now for another burn and hopefully the entire load will be consumed.
Pepe
I burned approx 30 pounds of fuel last night in 2 hrs and 22 mins. I was looking for a temp spike or point where I could refuel with the existing fuel still approx 4 " above the nozzles. I was about a 1/2 hr late, burned down to the restriction again, but I think I can start to get closer with my next burn. It’s pretty boring just burning wood and probably just as boring watching it. It was, however, informative for me. I ended up vibrating every 15 mins for 15 secs and had no bridging problems. I also shook the grate every 20 to 30 mins.
The vid is long.
This is the log I kept. The only real spike in temp was the hopper temp and (I learned the next morning) that by that time the fire had probably burned too far down towards the restriction. I’m thinking with a weighed load that establishing a time to refuel will be easier than depending on temps which seem to mostly stabilize .
Pepe
