New Muffler Preheater for 92 Dakotazag

Love the step by step, Bob. A real asset to the site. Pepe

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Very nice build
Sorry to hear that your shoulder is still limiting activity. That has been a problem now for about a year?
Did you get the first snow this week?

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The first snow hit the mountains but not in Wenatchee. Mission Ski/Snowboard Resort received two feet of snow, the earliest in over 50 years. There is snow in them hills, people living in foot hills still have snow in their yards, it might not leave. It frosted yesterday and today, first frost of the year. There goes the garden.
Yes the shoulder has put a stop to a lot of things I wanted to work on and do this summer. Trials and tribulations we will all have them at times in our lifetime, I Thank God He Helps me through them all.
Bob

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Okay, I was not satisfied with the temperature reading on my 14 mile run in the truck yesterday so I did the test over today. The sun had come up and was shinning on the truck yesterday and I think it gave a warmer reading in the hopper. So today I started the test just before the sun had shone over the horizon.


32 *f outside.

33 *f at the grate, EEEE reading to cold for the hopper temp.
But after 10 minutes of idling the engine, we got a good read out on the hopper.

36 *f at the grate and 34 *f in the hopper. Down the road for a 14 mile drive.

At about 8 miles the read out was 44 *f at the grate and 38 *f in the hopper.

Back at home with the engine idling. 50 *f at the grate and 40 *f in the hopper. Yesterday my hopper gage was blinking on the read out so the reboot put into EEEE and reset it.
Still the same conclusion the Preheater on the muffler is Working great. Also I have notice that I do not have to push as far down on the accelerator pedal to achieve 65 mph. It is about 1/8 + where before it was closer to 1/4 + on the throttle pedal. Now I need to go out and chunk up some more wood if my shoulder can handle it so I can go Drive On Wood.
Bob

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Bob, it would be intersting to to know the actual air temp coming straight outof the muffler preheater or going into the heatexchanger.
Heating up the entire gasifier (+heatex) with exhaust only will probably take some time before leveling off.
I remember @Carl meassured the preheated air going into the nozzles to 900F. I can’t remember if he mentioned the numbers from muffler preheater or heatexchanger.
I’m not telling you to install another tc :grin: but maybe someone else has a hunch of what kind of heat can be expected to be harvested from the exhaust.

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That is the next test that I am going to perform, using this.


I use them on my Charcoalgasifer for monitoring temperatures.
It also will Blue Tooth to my E tablet with a gragh showing both probs in real time. So the plan is one prob (A) placed right where the hot air is come out of the Muffler Heatexchanger and one prob (B) at the other end of the pipe going into the Drop Box Heatexchanger, this will check my heat loss using the ceramic wool insulation, not expecting any losses in temperature. But we will know how good the Muffler Heatexchanger works.
Bob

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The other thing is ambient temperatures outside. Summer air temperature of 100 *f is going be more effective than winter air temperatures in the freezing levels going into the Muffler Heatexchanger. But it is all wasted heat from the engine at work, and every little bit helps when you are trying to make woodgas.
Bob

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Thank you, I look forward to see what temps you will get.
There’s a third thing. With the gasifier lit you will only draw about 1/3 of the air through the muffler preheater. Longer residence time will mean even higher temps.

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I did close my air valve that is open when running on gas only, but with my auto mixer it is still in service all the time so I have air coming though both filters, So it was mixing a 1:1 air to air ratio instead of a 1:1 Woodgas to air ratio. So the flow though the woodgas piping was the same as if it was running on the gasifier making Woodgas.
Bob

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Several years back I put a thermometer in the tube delivering air from the motor exhaust heatexchanger to the drop box heat x . With the truck working and pulling I was registering about 200f over what ever the outside ambient temp was .

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Haha, I should have guessed you checked that at some point :smile:

But no wood giving off gas. Volume of air into a lit gasifier should be only 1/3 of the volume of the outgoing gas. Wood produces the rest.
Maybe you could put our theories to a test. With the probe mounted, do one test with a cold gasifier and one running woodgas. My bet is you get at least twice the rise in temp running woodgas :smile:

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200f is also what I am seeing with my barbecue thermometer before it goes into the nozzle inlet.


I plan to insulate the pipes and that might even raise the temps some.
image

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JO, you are thinking the same as me. That will be my next test, I just completed the last talked about test. Here is my findings.


I did not get prob 1 placed correctly in place, it did not make good contact with the steel pipe, should of used it for ambient temperature read out.
Prob 2 is the air just before going into the drop box heatexchanger. The ambient temperature was 50 *f when starting the drive. I when up Pine Canyon on Highway 2 and then up Badger Mt. Road. The highest temperature was at 192 *f at about 7 to 10 inches of vaccum pull on the gasifier at 65 mph. Boy do I have power now going up hill on gasoline. It was cooler at the top in the mid 40. That is where I had my highest reading, starting down hill it dropped off quickly and then had a short climb over the mountain. I normally pull 15 to 20 at higher speeds. Only if I floored it could I get it over 20 inches of vaccum for a short time, speed limit was 60 mph. the char bed is loose. Cleaned all the ash out on this run.
It leveled out 189 *f.

The grate got up to 92 *f, pulling over to take a picture it dropped to 90 *f.
I am sure when pulling a higher vaccum and with the gasifier in service it going to get a lot hotter.
Bob

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Amen brother.
A BTU saved is a BTU that can be put to useful work later.
S.U.

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