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Hydrogen-based Rotary Engine?
Seabird99 writes: "I came across this article at one of my car related forums and thought that I'd pass it on here. I have always been intrigued by "alternative" technologies where they relate to artificial locomotion." For some reason Slashdot gets a lot of submissions of wacko energy concepts - power from nothing, power from sand, power from a black box, engines that get 500 miles to the gallon... Perhaps this is more of the same, but at least it's an interesting write-up.
And now . . . someone has to come up with a way to generate hydrogen en masse and deliver it to your nearest filling station. Not to mention store it and dispense it there.
So long and thanks for all the fish . . . !!!
Storage and transport of hydrogen isn't really the problem anymore. Years ago, there were already test with hydrogen tanks that contained alluminium particles, which bind the hydrogen, making it a lot safer to transport and store hydrogen. Safer actually then a tank of gasoline.
(I wouldn't be surprised if these tanks are already widely in use now)
The problem is ofcourse to generate large amounts of hydrogen.
Given the succes of recent tests with fusion reactors, who knows.. we might be using hydrogen to create hydrogen from water.
quite a big if, but who knows.
"For some reason Slashdot gets a lot of submissions of wacko energy concepts"
Well maybe if you stopped posting them, these so-called "wacko" concepts wouldn't be submitted. Though I personally disagree, I would call these "desperate attempts at alternative energy"... and while it becomes tiresome to hear we should have 500mpg engines in 5 years, every year, for the last 5 years... as long as this research continues they may just live up to their promise someday.
Sounds like there's a need for a specific category/icon.
Mazda uses the Rotary engine desinged by Fellix Wankel, this is a nutation engine , it dosent have on single part in common, the Wankel (the Engine Mazda liscencded from NSU) is based on simple sealing techniques the nutation type engine couldnt be more different , I saw a live demo of a nutation transmission in the early 80's , eccentic shafts, cones, very similar to what they describe here , it was impressive to say the least, weighed about 70 lbs and was variable form something like a ratio of 1 to 100 and 100 to 1 varible under load and would handle supposedly 1000+ horsepower, it was on a diesel at about 200 HP and 400 + ft lbs torque and wasnt even getting warm, so I tend to belive those figures were possible, how you would utilize the same principals in a combustion engine eludes me.
I have a rotary engine invention too. I have discussed it with people from several likely manufacturers = the verdict is - "We don't want any new technology, even if its better than what we've got - we've spent a lot of money on cenventional engines, and we are happy with them."
Ideas like twice the power to weight ratio and 10% of the moving parts are not of any interest to the likes of Ford, even if (as with my engine) you could stick with the existing fuels, and servicing skills.
Years ago, there was all this hoopla about the "Gill Carb." and the supposed conspiricy to keep it out of production. This was supposed to give a normal car over 400 mpg. Eventually, it was finally shut down when it was demonstrated that there simply is not that much thermal energy in a gallon of gas. I've been fortunate enough to see a lot of these alternative engine designs. Many of them are pretty innovative and downright ingenious. So far, though, you always seem to run into something that doesn't work as planned. Bottom line is that the 4-cycle piston engine is hard to beat in terms of practicality and Carnot efficiency. So, this guy is telling me that his motor will not require a drive train. That tells me the engine is high torque with a really flat curve, already I'm skeptical. Add in no lubrication and I must assume his rpm's are low. I won't dismiss his engine out of hand, but I'd need to see the design.
A goal is a dream with a deadline
He seems to have a good grasp of the issues, and makes a lot of sense. He also has quite a few things going for him, such as:
I think this needs watching.
"...At the end of the day"..."when everyone goes home, you're stuck with yourself." RIP Layne Staley
McMaster calculates that 1,200 square feet of solar panels on the roof of a garage receiving 2,200 hours of sunshine a year could, with the help of an electrolysis device no bigger than a washing machine, produce enough hydrogen and oxygen to drive an MRE-powered car 200 miles a day.
Right, 1200 sq. ft. is 34 ft. on side (10.5m for people using sensible units). Thats alot of solar panels, leaving aside how much that many panels would cost, that a very big garage roof you've got there!
2200 hours of sunshine per year is 6 hours per day, unless you're living somewhere (very) sunny its unlikely your going to get this each and every day. So, erm, what happens in winter when you get a long spell of bad weather, you stop driving?
Finally, 200 miles? I drive over a thousand one day last week. Most weekends I do trips that average more than 200 miles one way. This isn't a particulary impressive total unless you use your car to commute 5 miles into work, and then go shopping at the local store.
The oxygen would be bottled in scuba-like tanks that would snap into place under the hood. The hydrogen, more volatile and more dangerous, would be piped around the car's chassis through 180 feet of tubing, divided into 3-foot sections, each sealed off from the next by a set of valves.
The hydrogen would be stored where? Distributed throughout the entire chassis? I really don't like that idea, that just increases the target area for collisions and does very little to increase safety. Most of the designs I've seen for this sort of thing store the H2 in cryogenic form in a (very) well protected tank, safety is usually increased by using some sort of honeycomb structure inside the tank. To be brutally honest, that seems far more sensible.
Al.The Daily ACK - Eclectic posts by yet another hacker
I didn't see any diagrams or anything. I would have loved to see some pictures and such. I dislike the fact that non of our goverments are pushing research into working solutions that doesn't pollute, and doesn't give money to the big oil companies (then the US can stop care about the middle east as well;)). Let those giants die, as there surely will step up new giants to take their place.
But I am rambling... I am just interested if there is anything you can read that would be more scientific and had more proofs. If the design is so simple, I can't see how it couldn't be hard to explain. Take an electrical engine for instance, that is a way easy aparatus to explain.
But it should be noted this isn't anything new. The internal combustion engine is innefficient by nature. It takes a spherical force (an explosion), redirects that into a vector force (up and down in a straight line), redirects that into a circular force, which is redirected into another circular force, finally driving the car. Each of those redirections wastes energy. Moreover, the fact that you have carbon monoxide and other hydrocarbon emissions is a sign of innefficient combustion: complete combustion of a carbon molecule goes all the way to carbon dioxide. There are plenty of legitimate projects to find a better way. Ben Rosen, chairman of Compaq, has envisioned the automotive powertrain market becoming like microprocessors, with independent companies competing to supply the most efficient engine. His Rosen Motors produced a working prototype of a hybrid-electric motor; they've since been taken over but I forget by whom.
Of course, a serious problem is the huge combustion engine and gasoline infrastructure. Even a much better product is not going to take over overnight. The internal combustion infrastructure would keep the economics of conventional motors attractive for decades, barring a serious kink in the gasoline supply.
It is a myth, though, that the automotive manufacturers are blocking this kind of thing. They're all doing research of their own. There is nothing a manufacturer wants more than to obsolete their own product and give everyone a reason to buy the next big thing.
The other technology discussed here is photovoltaic (solar-electric) conversion of water to hydrogen for combustion. I think this is far more theoretical. Not that you can't very simply and reliably bang an electric current through water and get combustible hydrogen and oxygen. But from what I know (and I do have some knowledge on this subject) I seriously doubt whether existing photovoltaic cells are efficient enough to supply the power for even a very efficient automotive engine by splitting water. It should be noted that like anything else, this conversion of electrical power into chemical power represents a loss of efficiency, so the purpose for doing this is to get the benefit of a combustible fuel.
Direct solar cleavage of water to H and O is one of the holy grails of both hydrogen power and solar research; this photochemical process is at the heart of how plants utilize the energy of the sun and hence the source of most energy on earth including all fossil fuels. We aren't there yet. It can be done but it isn't sufficiently efficient to be practical. There are tons of novel catalytic techniques being experimented with, where rather than go through a photovoltaic cell (the conversion of sunlight to electricity of course represents another inefficiency), sunlight is used as the power source to directly, catalytically cleave water. I think within a few decades this kind of thing will start to make significant inroads, provided countries like Iceland and companies like Daimler Chrysler continue to pursue hydrogen research and a hydrogen energy economy.
I don't see anything in the article, however, that suggest this motor could only run on hydrogen. So it may be a valid concept that it much closer to commercial reality.
It Is the Nature of Information to Transgress Artificial Boundaries
Okay, so nobody's bothered to check up on google, yet. His web site includes a lot of more detailed information. Check it out, then let's discuss what's there, not just what's in the article.
Yes, the guy's a little, er, fringey -- one of his other projects is an antigravity machine. I'm not saying such a machine is impossible, just that I'd not expect anyone who's not, say, Stephen Hawking, to come up with one.
That bit of weirdness aside, what do people think about the engine itself?
First, the fuel. The article implies that it uses Hydrogen. We've discussed to death the problems with using straight hydrogen as a fuel, which ultimately (putting aside safety and infrastructure issues) comes down to energy density -- pound for pound (or liter for liter), Hydrogen gas just doesn't pack as much punch, specatcular disasters caught on tape notwithstanding, as gasoline. However, the page talks about using a mixture of Nitrous Oxide and Ammonia, ignited with a glowplug, not straight hydrogen. It does speak of a catalyzed reaction being researched to derive the fuels from solar power, air, and water.
Questions: Is it likely that such a catalytic reaction exists? If not, will it take more fossil- or nuclear-fuel energy to create, using other reactons, the needed amounts of nitrous and ammonia? Would that added cost be worth it to reduce fossil-fuel emissions from cars? (let's ignore issues of infrastructure for now...)
Next, there's the design of the engine itself. Basically, it appears that it's an angled plate in a cylinder, with the reactive explosion happening first on one side (causing the plate to rotate around the axis it's mounted on), then on the other. Nifty idea, simpler looking than the Wankel rotary engine, and MUCH simpler than the internal combustion engine.
Questions: Can such an engine really operate, with any fuel? Could you really run it at many different speeds, and if so, how would you manage that? (I'm not personally convinced that you could do without a transmission). Would the "chambers" formed by the rotating plate provide any compression for the fuel (a major requirement for traditional engines)?
Let's not dismiss this entirely, out of hand, as a wacko idea. Look at the web pages in detail, ignore his strong claims and "past performance", and just focus on the ideas presented. I'm intrigued, but don't know enough about chemistry or mechanical engineering to pass any kind of judgement (and I suspect most of the people here don't qualify, either.) Those who do qualify...what do you think?
david.
If/when this idea pans out and a working prototype is produced, all the companies that profit from the "noisy, dirty, inefficient contraption" that the internal combustion engine is will buy up all the rights to it and shelve the idea for all eternity. It seems utterly absurd that no truly novel engine advancements have reached us in the recent past. Many of them certainly are impractical. But with all the people doing research all over the world, some must have come up with something. And then enter in the companies who make the poor grad student inventor rich as long as (s)he keeps it quiet. Voila! No innovation.
For those interested here (english ver) is an interesting engine I saw on tv a year or two ago. Unlike the story above they have working protypes, most that I've seen (on the site and tv) are just the engine but they also have tried using it in things (chainsaw for one).
-Torawk
They can be more efficient than piston engines, and unfortunately research on rotary diesels seems to have stalled years ago, but there's many advantages over pistons for engines that aren't required to change RPM often, such as generators.
I used to have an Arctic Cat snowmobile with a Wankel engine when I was much younger. We couldn't find anybody to service it when it started to die, but it was fun to take it apart, it's extremely different from the tiny chainsaw two-strokes and four-stroke lawnmower engines I had torn down before.
AC's cheerfully ignored
He revolutionized glass. Why couldn't he apply the same non-linear thinking to his first project, add modern materials, and make it work?
Woot w00t w007.
... I always felt that a closed-cycle gas turbine (Rover experimented with one in the 50s) combined with CVT (Continuously Variable transmission - eg DAF variomatic, Uno Selecta) would be a good way forward.
Gas turbines are effecient (insert something clever to do with thermodynamics here)and can run on anything from coal-dust to hydrogen. The problem is - IIRC - that they only really work well within a narrow range of speed so coupling them to either conventional (stick-shift) or auto transmissions never really worked. Coupling to CVT should allow the engine to always spin at an efficient speed. Piston engined cars with CVT get good gas mileage - but people don't like the fact that the engine note stays the same as they accelerate.
It would run good on hydrogen (should be very little H2O2 in the exhaust burning like that), but I still don't have a solution to producing and storing H2.
This sig made only from recycled ASCII
If McMaster's engine is all that he claims, he'd be making a grave mistake by targeting the automobile industry whose entrenched practices will almost certainly stop any progress.
What McMaster must do is form a small engine company for more innocuous things like remote controlled planes and lawnmowers. There is not a huge infrastructure that will block progress in these industries. If he can show his concept will work on a small scale, only then will people begin to even consider it for more large scale uses.
[Oil companies] don't have a monopoly on water.
You're right. They don't. Now Monsanto on the other hand...
Nice things are nicer than nasty ones.
The ring passes through a vane on the top of the animation that seals the combustion chamber. Because the ring rotates, the location it passes through the vane moves, so the vane has to oscillate back and forth. Furthermore, because the ring is tilted, the angle where it meets the vane changes throughout the rotation. You could match it by giving the vane a circular rotation, but the angle at which the ring meets the vane will constantly be changing. The vane will either have to be very thin, or the seal won't be tight.
The ring's rotation axis isn't a minimum or maximum moment of inertia. This thing is going to wobble.
I'm not convinced ring will hold up under load. You have to remember that if this engine is producing 200 horsepower, the force to produce all that torque is going to be pushing with equal pressure on the entire internal surface area of the combustion chamber. Conventional internal combustion engines and Wankel rotary engines get around this by using nice, thick chunks of metal (engine block, piston) to contain the combustion chamber. This engine is going to try to contain the combustion with thin plates which look like they comprise at least half the internal surface area. They're going to bend out of shape if you try to generate too much torque with this engine.
Ya', if you push a rotary into detonation then you do indeed run into reliablity "issues". However if you do not abuse it and stay within it's design it runs just fine for MANY miles. How many 1st gen RX7 do you see on the road? How about on the track? SCCA has an entire racing series dedicated to the little buggers! They're not perfect, they lack torque, but kripes they spin to 8K easily and if correctly geared make for a really wild ride. I worry that mine will blow but it just keeps going and I AM outside it's original design parameters :-) I worry that my other vehicles will blow too for that matter (lol). A shame they didn't turbo this new one - 10K redline is cool and all but imagine the difference it was forced induction!
Perhaps a little experience is in order for the original poster or he's abused one - been bitten - and is just upset about it? At least they don't cost a mint to replace, I could build two rotaries for what one decently built V8 runs...
Heh, and if you look at the animations of this new guy's engine it's obviously not a Wankel. I DO wonder where the heck the exhaust goes though. He claims no exhaust but I find that a bit hard to believe. In addition, if it's got anywhere near the temps that a Wankel has, due to the way it dumps damn near straight out of the cylinder, then the exhaust is going to be pretty hot. I'd like to see\hear one of those running. Wankels are pretty darned LOUD (exhaust) too!
Build it, Drive it, Improve it! Hybridz.org
Studies like this are fairly artificial since they often simplify the situation and make some questionable basic assumptions. For example, in the late 80s I remember reading a study that proved that a farm which relied on sunlight, the labor of the farmer and his animals and no other external energy input was not self sustainable. Which leads one to wonder, how did we manage to not only survive, but proliferate in the days before fossil fuel?
In any case, the best answer may be a hybrid coal/methanol system as reported in this recent paper. They claim to be able to reduce coal usage by 2.6 million tons and reduce CO2 emmissions by 2.15 million tons while producing 15.4 billion kWh of electricity.
If electricity is produced by electrons is morality produced by morons?