I would try a tee with a water hammer arrester. It is just a piece of pipe that stick up and a cap on it. It creates an air pocket in it, and air of course compresses more then water. It is essentially a mini water non-bladdered water tank.
If it is a just a regular pressure switch like you would find on a well pump, that is just a set of springs with a diaphragm, that open and close contacts(a relay). They are technically adjustable, but don’t bother. If it is stalling it has too much pressure and isn’t shutting off. It may also have some other delay to prevent constant on/off cycling which burns up the contacts on the relay, and can overheat the motor.
That might work for both. Yeah I might have to try that thats a good idea and really simple.
No these are small din connect type relay switch. Basica concept is the same they just dont have the resolution we need. This is nothing new if you look up precsion low volume water flow control its a known problem with simple set ups like we are using.
Another simple device would be a PVC housing to contain this hose. If you can expand this hose inside a housing to constrain it; it can act as a tiny accumulator. Could make air tight to compress the air ouside the hose or vent the housing.
I would try just air first. It is simpler. You are going down the path of inventing a bladdered water tank. Which is essentially an innertube or balloon inside the tank blown up to a certain pressure. They do provide a more constant pressure. however the main advantage is they don’t waterlog (over time air absorbs into the water), and that isn’t going to be an issue.
Well I just concluded this run and it ran 3 1/2 hours on 13 lbs of fuel, consumed 5 litres water @ 850 wats. I have to say this was probably one of the most stable runs Ive ever seen. I made a few adjustements but for different reasons. As it warmed up it could consume more water. So I was basically turnning it up not just trying to get the flowing going again. That part I think is solved. I think the only way to make it better is with simple controller using a temp probe inside the nozzle with fuel injector type pump.
This run has convinced me even more that if we can get the flow stable and inject it as fine as we can or pure super heated steam the more we can get in there. I had that thing blasting in there and there was still plenty oxygen. You can tell by the glow.
Thanks so much guys for having this water discussion under my downdrafter topic! This is really helpful as I try to get my system optimized. I think figuring this out is important for reaching maximum power and for extending tuyere life. I do wonder if the water carburetor idea still has merit. I would have to close off one end of my tuyere pipe to make that work. I noticed that when I cranked up my water flow that the Leidenfrost effect created marble sized balls of water in my tuyere. I don’t know if my water wick idea has merit. the one made of fiberglass gasket rope also melted.
I think a water venturi effect mixer is the right way to go. As far as I can tell its the simplest way to get water in there proportional to air flow. It worked for making gasoline-air mixtures for us for so many years. Those gasoline-air mixes weren’t as precise as the flow sensor, O2 sensor, thermocouple → injector systems we use now. But I think we can get away with that tiny bit less precision for now.
The main difficulties I would anticipate in a water injection system are freezing and microbial growth. So I would look at other systems that deal with these problems. The one that I thought of is the windshield cleaner spray system that cars use. Windshield cleaner is 50% methanol, which both stops microbial growth and prevents freezing in winter.
Rindert
That is one reason for going to the pump. Now the water is stored in bucket you simply put away in a warm place when not in use and clear the pump. When in use the gasfier heat is used to keep things from freezing.
Steam convertion I think is better than raw water injection. When you flash the water to steam it is effectively cooling and sucking the heat out of the nozzle. I will never degrade if it never left to run dry. Then the steam is to a higher temp making it easier for the water shift.
Since he is looking for 100% saturated air, fogging mister nozzles or ultrasonic misters used for hydroponic or aeroponic or plant cutting grow chambers would saturate the air with a fine foggy mist then just suck that air into the nozzle. It would be a separate box, and would add bulkiness to the system, which I don’t blame him for not wanting to do. The fine mist of course would turn to steam faster.
As a mist or as a regular liquid, water expands ~1000 times when it flashes to steam. This will create backpressure that the system will have to deal with. Matt seems to have that sorted out, but it’s not trivial.
One suggestion Matt had was mixing gasifier air with already expanded steam rather than liquid water or water vapor to avoid this backpressure (think he said as much earlier in this chain). You don’t need the steam to be especially high temperature or high pressure, just steam instead of water. A hot muffler would do the trick. Matt and I had some back and forth on this a few months ago.
water actually expands like 1600-1700x. I am also not saying Matt should change his system.
What I am saying is micro droplets, transition to steam faster. The effect of the expansion is going to be controlled by the airflow into the system, which is dictated by the air being drawn out of the system minus the expansion of the water into steam. The faster the transition to steam, the less likely a blow back occurs because it is done on the intake cycle. If it doesn’t transition on the intake cycle, it is in the reactor, and will expand in the reactor causing the blow back.
Similarly to the current issue, the startup sequence until it gets hot enough to convert all the water to steam fast enough, along with the ability to crack it, it is going to create issues.
My system the steam expansion is the same as evaping inside the nozzle tube. The water is flashed on the spot inside the nozzle and it blast out inside the intake tube. Its no different the intake air volume displacement doesnt change.
In this pic bellow. this is the top side of the inner air feed tube. Note the hole this is where the steam enters inside to mix with intake air. The tubes you see on this side are spacers to center the core tube plus they act as a baffle. The tube you see on the top photo is the water feed tube and this extends inside to force the water to the hot end of the nozzle.
Hello Matt, I like your nozzle design, the tube leads the water towards the hottest part of the nozzle, where the most intensive cooling is needed, while at the same time the water evaporates and the steam is superheated to a very high temperature, so the cooling energy is not lost, but is returned in the form of superheated steam to the gasification process, this method should provide a strong gas with a lot of hydrogen. In the picture you can see a small hole more at the beginning of the nozzle, which will allow a high speed of the superheated steam, which will mix well with the fresh air in the tube, well, you just need to balance the steam / air ratio, and a “turbo” gasifier will be created.
Correction steam / atmosphere displacement is the most effective part of the cooling process. There are three:: water heat absorbtion, water to steam conversion and then air to steam displacment.
Yup that is where Im at as well; I think I now have the system where I will be able to find that ratio or Im am at least one big step closer to getting there. Im trying to envision this what should happen with all thats taking place. I think there will be a point where the air / Steam ratio will get to a point where the heat is just not there as the air is too deluted with steam. So steam stops producing, reaction gets hot again and then this process starts over. < that is what I want to see that means I found the limitation and then have that target to tune too.
Ok for you smarty pants what do we call this event?
Theory: What I think should happen to reach this maximum point of steam to air ratio verses volume output is there should be a point of oscilation where the ratio becomes too high where the air is too deluted. > reaction cools down > Steam production stops > air / steam ratio less deluted > reaction heats up again > steam production increases > Air / steam ratio becomes deluted again.
This is theory I believe I will see when I achieve this threshold where the steam is more than the air intake can sustain heat production to sustain the process. Im sure there is some technical word I could use to describe this scenario but it escapes me.
If we want to achieve a stable steam/air ratio, this is possible by the size of the air inlet opening compared to the size of the steam inlet opening, of course, the condition is that both media are at the same pressure. If a higher pressure is created inside the steam gasification chamber, the ratio will collapse. This thinking leads me to the idea that it would be a good idea to drill a smaller hole in the lower part of the nozzle, which would serve to equalize the pressure and drain off excessive amounts of water if the dosage was too high. In order for the water to drain off, a smaller nozzle slope is required,…
Another way to control the overpressure of water vapor is to use this small overpressure to control the water dosage, for this you would need a sensitive diaphragm valve (similar to the one used to regulate the pressure of propane).
Im looking for the word to describe this event. This should happen on any situation there will also be a limit somewhere that this will happen on any system.
The system isnt broken here. the hole is plenty big enough and there should never ever ever ever ever be any water drainage. If that happens I have failed in the desing. The pump should never ever introduce more water than the nozzle can convert. Ive already hit that block and why this new version exist. I can only get 4 to 5 litters or water. This not even close to where we need to be. We need to be consuming 2 ltrs of water per one 1 kg of charcoal and this is the minimum we should be achieving.
BTU ratio: 2 ltrs of water is roughly equal to 1 kg of charcoal. 50/50 ration is the first mile stone I am trying to achieve. I am only half way there hopefully this new nozzle will get me past this point.
I do think my thinking is backwards where the vent hole needs to be. The reason I put it where it is back closer to the front side is so that if raw water does make it into the tier tube it can evaporate there. But what I think was happening on the old version is water cant even get to the tip and what steam is being produced is pushing the water away from the end causing it to splash out.
What I think I should be doing is placing that hole closer to the end. Then any raw water would be forced to the end to get out the hole right? Well that should never happen becuase there is plenty heat here to flash it to steam.
So I do plan to make test nozzle later with this revision but Ill need a test mule. Its too expensive to make this nozzle just to throw it away if this dont work. A tig welded production version of this nozzle I will have to charge pretty close to $500 bucks just for this nozzle. Thats not including the gasifier. lol. Yeah 100 bucks just in SS parts, then machining out that bushing, then tig welding it and make it all pretty lookin like I know what Im doing lol yeah it an entire days work plus parts, materials and overhead.
