So this idea is still alive? There is no post in the thread for more than half a year.
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Hi Kamil, I’m still FOR the meeting, only a “higher” force can prevent me, well, now it’s winter and other work, but it would be good to “rekindle” that topic.
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Same here. If we get our van running till summer, we are coming.
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Here is a sketch of the idea of damping the pressure fluctuation in the intake line, I think this will also have a beneficial effect on the operation and efficiency of the engine itself, …
think about it,… if the throttle valve is directly in front of the intake valve, the engine has to invest a lot of energy when sucking through the closed valve, it is especially “difficult” when the crankshaft is at 90° and the piston is moving quickly,…
if we compare this with a freely open suction line, which is under negative pressure, we will find the difference
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Good morning Sir Tone
I may not have followed your thread as well as I should have but just a quick look at the above drawing makes me ask the question .
Doesn’t gas and air mixed in a container plus a small burp or backfire equal boom 
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Mr. Wayne, my thoughts are scattered, as are some of the posts scattered around this forum,…
In the attached link, the opinions of others are the same as yours, well, I have to make a compromise between the pulsating suction through the mixer and the risk of “bumm”, …
Years ago, we did an experiment: we vacuumed a 10-liter cylinder made of thin sheet metal (which contained freon) and (we previously installed a filament for ignition) and filled it with a mixture of acetylene and oxygen to approx. 2 bar. We placed it among high stones and ignited with a long cable… we were expecting a strong explosion but we were disappointed, we could only hear the whistling of gases through the safety opening, which opens at approx. 30 bar.
How much does the pressure rise when the air/wood gas mixture ignites? I think that it will not exceed the pressure of 2 bar.
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Oef, some catching up to do on the Horsepower link.
For the damping of the pressure, that was my first tought too and it didnt help me 
. I think Mr Steve experimented with a Lister that way with the same results. Could you give an estimation of what the volume should be? If you really think it will help I can give it another try.
Helmholtz resonator is to complicated for me. The generator is at a steady 1500 rpm/ 25 Hz zo a long pipe with inverted pulse will do the job, I hope . It would be around 7 m if my calculations are correct. But how are the pulses influenced by the in between barrel? Glad to learn
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The issue I see, is that there is drag on the gas side, and none on the air side, so it will naturally pull more air in then gas.
The point of the air tank is to even out the pressure to get the gasifier to have a more even or constant draw. the stop/start of the draw from the single piston plays games with the gasifier.
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Tone a new thought if you are going to try this.
Use a small well pressure tank with an air bladder in it maybe? To work towards pulsation dampening.
Your particular engine is no-doubt low RPM, so fewer pulsations to deal with.
Tune the above normal air pressurized pocket: pre-charged pressurized. Maybe even tied into the crankcase pulsations.
S.U.
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Steve, l had thod about this also. Had to cover my filter one day on my single cyl BCS with a tractor inner tire since a backfire shot my lid somewhere and l observed it pulsating. Will for sure invest more time in this idea.
Tone, you are crazy 
specialy since acetylene is known to “self destruct” under pressure, thats why its in solution it the tanks… but l get it, l too did those kind of things, and often wonder how am l still alive
I wuld guess in your case, the fuel/oxigen ratio might be off. Is that possible? Because if mixed right, and under that pressure, you shuld definitly get a detonation (supersonic explosion) and that shockwave is what does the damage.
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Or the fire didnt get into the tank and burned just outside. Woodgas is less potent but if it goes wrong, it happens on the inside and outlet should be big. Just my thoughts and I am the stupid guy in the room.
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I did some calculation and seems Tones observations are legit. In best case scenario, an explosion of 2bar oxy acetilene in a close enviroment shuld not exceed 50 bar. So, if the material survives the deronation (if it occurs) then a vessel like that shuld survive the pressure well. Also, since it cools rapidly, it shuld come down to close to original pressure quite fast as the ratio of oxy/acet and burn byproduct at same temperature is almost 1/1 (5/6).
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If we take the example of a mixture of gasoline and air at an ambient pressure of 1 bar, which is ignited in a closed container, well, the question arises here, by how much does the pressure rise at that moment? I assume that this pressure is 3-4 bar. If we take the mixture of wood gas and air as another example, the pressure after combustion will reach only a little more than 2 bar. In fact, this increase in pressure allows the engine to run, but here in the cylinder on the suction line, it cannot cause damage.
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At the moment of explosion? Shuld be a lot higher thain that… but whatever it is, its not high enaugh to make a bomb, if built correctly. I mean l had filters blown up by offgas/air mix (super potent), and it only threw the caps off the pvc sewer pipe filter. With some force, sure, but nothing life threatning…
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Ok my back of the anvilope calculations say it shuld shuld teorethicly be about double of that Tone, if we say woodgas burns at moderate 800c. Still, l agree. 5 bars peak is nothing for a well constructed vessel. But the only problem l see here, when the vessel goes poof, engine has to suck all the dead gas first. Happened to me when l had a small crack on my BCS gasifier. It sucked just enaugh air in that occasionaly the filter wuld popp. It threw the lid of first, then l fixed it on better. Like you say Tone, it just puffs and hisses but the sistem needs to be blown with the fan again. No way the engine wuld start with the “dead gas” in the sistem…
And man was it frustrating… thod the engine is backfireing but in truth its always one of 3 things. Leaks, leaks or leaks.
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Just a big tube burp! I thinking of building your type of filter for the front-end of my 1995 Grand Cherokee Jeep. I think I will put sume sort of lines or cables on the end caps just in case of a big tube burb! They will be there just hanging there in the wind from the filter.
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If you got space its a nice way to hide a large surface area sock filter. But truth be sayd, the popping there was entirely my fault. First, l used a 12v vacuum cleaner as a fan, draw gas trugh the brushes. Never do that now l learned… second, the air culd be sucked back from the mixer valve trugh the filter. Bad bad idea… we learn with scars, and bangs
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Tone, forgive my ignorance, but aren’t intake runners built to certain lenghts and widths for a reason? Long and narrow for low end tourqe - short and wide for high rpm power. Or does that hold true only for multi cylinder engines?
To avoid risk of bangs, would smoothing “reservoars” prior to the mixer be helpful?
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In this combination, you risk inadequate operation of the engine speed controller if we are talking about a generator. The frequency will be very unstable.
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Kristjan stated the combustion temperature of the wood gas-air mixture at 800°C, now I have data to calculate the pressure upon ignition, which is 3.9 bar, if it does not cool down on the walls of the container, this is also good information for other purposes. … such as calculating engine power and torque. Anyway, thank you for your opinions, which I will take into account.
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