Continuous Fuel Combustion
Continuous Fuel CombustionFor perfect propulsion, a motorcycle design:
The continuous fuel combustion engine is an optimization of physics applied to motive force.
We all know that the ubiquitous piston-engine (or "discrete fuel combustion" engine) that dominates the motorways. It has pistons that slap back and forth many times a second which translate into circular motion. It runs between 20-30% efficient; with fuel injection, there is a theoretical ~50% efficiency possible, but no one has built such an engine (AFAIK). Most of the energy still gets lost via the radiator and the constant inertial loss made by the mass of the pistons having to change to the opposite direction on each cycle. It has many moving parts because of its complexity which means it is also inefficient over the life of the engine, creating maintenance burdens. The inefficiency of piston engines also means that a transmission (or mechanical speed converter) is necessary for road use because you can't "rev" the motor at high speeds without it falling apart and you are limited at the bottom end by stalling. This converter itself is complex and means more weight and inefficiency.
Secondly, the piston engine requires hi-voltage sparks which creates a need for energy generation. An alternator and hi-voltage transformer. More inefficiency and complexity.
A CFC engine on the other hand, can be likened more to a jet engine, in that one has turbine fins along a cylindrical axis which rotates. Call it a 1-stroke engine. The idea is continuous propulsion along the entire length where the explosion expands. Speed is determined solely by fuel rate. There is only one spark to start the reaction until your burn is done. Since there are few moving parts, speed is limited only by fricative forces on the primary bearings holding the rotational load. RPM rates are not as limited because you're creating a very efficient conversion from outward force to rotary motion (no changing direction of piston heads). Very efficient. I would estimate that it would be nearly 4x more efficient than current piston engines, and possibly less then half the weight as there's now no need for a transmission. Further, maintenance and parts inventory is about 1/100th of current engines. This design will make every car on the road obsolete.
Now, for the motorcycle, take two of those, mount one on each side of a two-wheeled bike, with a direct drive to a double-sided, singly-geared hub. Each turbine revolves towards the center of the bike to prevent (unlikely) resonance that could tear the bike apart. Helical gears on the drive train for continuous, smooth force distribution. No transmission is necessary: fuel flow controls the amount of force and an ignitor at the foot to start the combustion from stop to go.
Pressurized fuel system (patent pending), rather than a fuel pump, that is initially set when re-filling tank via a hand lever with over-center clamp. A bleeder-piston between engine combustion chamber and the fuel tank that uses a small fraction of the pressure from the combustion to maintain a fixed air pressure at the top of the tank, for the full range of acceleration. Once you get up to speed with the assistance of the pressure, gravity and the "bleeder-piston" will do the rest to keep consistent fuel availability.
Rear tire should be fat and rounded, perhaps as much as a foot wide, to prevent skidding at high-speed on corners with debris. Consider front and rear tires being interchangeable, but might make the front wheel too massive for steering, but then this thing is made for high speeds where it won't be a factor. One could even consider the rim to be interchangeable, since there's not much complexity like chains or gears.
Front faring should at least cover the top half of the wheel where it rotates opposite of forward direction. Rear faring covers back of the wheel only enough to prevent water from flying up towards rider.
Horn? Real motorcyclists don't honk through traffic, they accelerate.
Color: Black or all Chrome so you never see it moving. A panel on right-side of the bike so you can show where you've been. Capacity to take one passenger along.
Name: Cobra Velociraptor. Boom.
-- MarkJanssen, (patent pending; engine co-patent with Britain; inspiration from a Disney movie.)
Sounds like you've re-invented (or just developed an appreciation for) the gas turbine. Unfortunately, it's inefficient for human transportation outside of aircraft, particularly because it's so technically awkward (read: needs a transmission, a lot of transmission) to convert the high-speed, low-torque, narrow-speed-range output of the turbine into the relatively low-speed, high-torque, wide-speed-range force required to drive a passenger vehicle at normal road speeds. Major manufacturers have been trying to put turbine power into passenger vehicles since the mid 1950s, with limited success. The end result tends to be less fuel efficient than a piston engine, and considerably more costly to manufacture because it's expensive to make heat exchangers -- which you need, to absorb noise and prevent the hot exhaust igniting nearby pedestrians -- and turbine blades that can withstand the extreme stresses to which the turbine spool and ancillary ducting are subjected. There are some turbine-powered motorcycles, but they're mostly show pieces or one-off experimentals -- not practical, even by the usual motorcycle standards which admit a pretty broad definition of "practical".
When I google "gas turbine" I see jet-type engines of absurd complexity. This engine would not need it. As far as torque/speed, there are ways to handle that, make your outer "shell' strong to handle the explosions acting as the compressor, so the energy gets converted into torque.
The "absurd complexity" is to provide necessities like oil circulation, cooling, fuel pump, electrical power generation, starter motor, exhaust heat recovery, a multi-stage turbine spool so you can stall the engine without having to re-start it, air bleed (to power accessories), transmission for shaft-drive, engine monitoring systems, hydraulic power, and so on. Turbine engines can be quite simple, though. An Allison 250 is simple and has been used on a limited-production motorcycle. See http://en.wikipedia.org/wiki/Allison_Model_250
No, there is no need for all those vanes for "compressing the air". That takes work to accomplish, so you're going to get no yield of extra energy. Totally wrong. Electrical power generation? Show me. I think no physicist designed jet engines.
Actually, there is a need for all those vanes "compressing the air". Without it, you don't have a gas turbine that generates power, you have -- at best -- a really inefficient gas burning heater. See to learn how a jet engine works. As for electrical power generation, I assume you intend to have lights on your motorcycle? If so, you're going to need an alternator to recharge the battery, and your jet engine is a good way to power it.
As for the "outer 'shell'", the problem is not shell strength. The problem is that the compressor needs to turn at high speed in order to maintain a high enough intake pressure to continuously compress the air-fuel mixture and keep the expanding combustion gasses from exiting through the intake. The alternative is a reed valve or other intake control mechanism. These are used in pulsejet engines, but they have their own problems.
This is bullshit, you simply are not a physicist. You've been programmed by the NovusOrdoSeclorum?.
I don't have to be a physicist to know how a jet engine works. I haven't been "programmed by the NovusOrdoSeclorum?", I've been taught by engineers.
By the way, a 1-foot wide front tyre will make the bike handle like a speedboat with a heavy rudder. It's fine for off-road use, but on-road... No.
I don't think so. As long as the tire pressure is maintained, your contact patch should still be small enough not to cause problems. Your issue is applicable to turning, but that can be counteracted with leaning into the curve and maintaining speed. But it is making me think a bit, there will be tire wear on the front during turns with a slow-sloped fat tire. Proper tread might handle that.
It won't cause problems per se, it just won't handle very well. It's fine for a low, slow cruiser or an off-road bike, but not very nimble around the twisties or in town. Not that it hasn't been done before. See http://thekneeslider.com/american-motorcycles-300-front-tire-movie-chopper/ and http://www.totalmotorcycle.com/motorcycles/2013models/2013-Yamaha-TW200.htm
One foot may be too much, but really the only issue is the gyroscopic effect.
The main issue is flicking all that weight around.
[[STUB]] Extra thoughts...
We have a machine that's going to be accelerating and decelerating often. Since were aiming for efficiency, we need a way to transfer power back and forth between the bike mass to the turbines. Consider mechanically transferring forward momentum to a flywheel(s), for braking. and then transferring it back to the turbine to restart.
The flywheel is, if done right, is the main brake. A secondary, caliper brake on the front wheel augments stopping power and control. Have the flywheel spin in the direction so that emergency stop pulls downward towards the front of the bike, possibly activating a friction bar at the top of the wheel. Front wheel won't lock, as on a normal bike. No need to dissipate power through friction and heat.
Flywheel momentum is a function of mass, speed (rpm), and radius. Mass on the bike for the flywheel is fine as long as it gets transferred efficiently back to the turbine to ready propulsion, speed practicality will be limited to friction, radius is good because mass increases exponentially towards the circumference. Think a cylindrical mass about a foot long made of a heavy metal (uranium tailings?)
Coupling between flywheel and turbines can be direct, straight-line, surface-to-surface clutching.
Not unless you can invent a slow-speed, high-torque, wide-speed-range turbine engine. Otherwise, you'll need a transmission to match the high-speed, low-torque, narrow-speed-range output of a typical gas turbine to the low-speed, high-torque, wide-speed-range requirements of passenger vehicles.
For fuel control, pressurize the fuel into a tank at refill station or perhaps use a line from the combustion chamber to pressurize the tank. Controlled by dual throttles at handle-bars or at feet since transmission control no longer necessary, one at each limb. The idea for separate throttles for each turbine is to master the bike. The body picks up subtle forces which will inform the rider of the *state* of each side of power.
Your dual throttles are literally frightening. There's a good reason dual engines are illegal in many jurisdictions; loss of synchronisation can, under the right circumstances, result in a significant amount of kinetic energy -- equal to the difference in power output between the engines -- being directed away from the normal direction of travel.
Compression ratios have nothing to do with "checking the integrity of an engine". Compression is necessary, and the higher the compression ratio, the higher the potential efficiency of the engine (for a given fuel). See http://en.wikipedia.org/wiki/Compression_ratio starting with a "high compression ratio is desirable..."
Compression is only necessary on a diesel engine, where it is used in place of a high-voltage spark to ignite the fuel. PayMeLater?.
Compression is necessary on any conventional internal combustion engine. Without it, the thermal expansion of the burning fuel will be inefficient and won't produce enough power to do useful work. Some very early piston engines were compressionless, but as a result were very low-powered. In-cylinder compression is what makes modern engine designs efficient and powerful. Note that the energy required to compress the fuel-air mixture is like compressing a spring; all the compression energy -- minus negligible losses as heat -- is returned in the expansion.
You see, you're one of the deluded. Indeed, in a spring it is returned, but then there is a certain resonant frequency in which no work is involved. In a car engine, you're not in that fixed range where the natural return rate is equal to the rotation of the crank. If you were to tie your spring to a heavy pendulum, you'd be oscillating chaotically all over the place, and the work you did to compress the energy would hardly be turned into useful work.
No, I don't see that I'm one of the deluded. If I did, I wouldn't be deluded. It's also not clear to me what point you're trying to make. Are you suggesting that in a piston engine, the compression and decompression rate will not be at the natural resonant frequency of the air in the cylinder? I suppose that's true, but the resulting inefficiency (emitted as heat) is negligible. Attempting to eliminate that effect by building a compressionless engine would result in much, much greater inefficiency.
You might find the following infographic helpful for understanding how modern piston engines work: http://animagraffs.com/how-a-car-engine-works/
[I think he has switched back to arguing his "inertial loss theory". All he's managed to accomplish with the switch is to show he doesn't really understand springs either.]
Ideal fuel is probably leaded gasoline.
Leaded gasoline? Really? Haven't we spewed enough lead, other additives and hydrocarbons into the atmosphere? A benefit of turbine engines is they can burn flammable rubbish that piston engines cannot.
Here's the thing, it's not leaded gasoline that was really ever the hazard -- it was millions of cars on the road, period. The cost of un-leading gasoline probably negates the imagined environmental benefits.
Lead in gasoline is an additive; it does not occur naturally. It's cheaper not to add it. For gas turbine purposes, gasoline has a low flash point which makes it dangerous. You're better off using Jet A, diesel fuel or kerosene, which have a higher flash point than gasoline and are all relatively affordable.
That's not what I learned. They call it unleaded because they had to take the lead out.
You learned wrong. You're probably confusing gas with coffee. Coffee naturally has caffeine that has to be removed to make it decaffeinated. Gasoline doesn't naturally have tetraethyl lead, so it's left out to make unleaded gas. See http://en.wikipedia.org/wiki/Tetraethyllead
[[Claim regarding fossil fuels removed.]]
The turbines to drive-train:wheel to braking/flywheel to turbines forms a complete loop-cycle of power maintenance, going up or down, minimizing loss, for a perfect system of motive force.
See above re the problems of gas turbines in passenger vehicles.
Thought.... Rim braking will make it easier to stop with less force and wear.
Rim braking is good, but fails utterly if the rim is even slightly warped. It's better to use a rim-mounted disc, like on this Buell:
Hmm, that would be acceptable. I think rim being warped won't be a problem, though. Bicyclists already solved that problem by having a single pull for the two sides.
The problem isn't that the brakes cause the rim to be warped, but the fact that braking force is drastically reduced if the rim becomes warped.
For braking, a second geared assembly, going to a weighted flywheel. Wanting good acceleration, means less mass and maximize radius.
Upon unthrottling, the drive train is released, the gear is removed from the rear wheel. A second lever for braking applies the flywheel braking to the outer rim.
Faring should go all the way to the aft-end of the wheel for catching water.
Electricity generation: needed? Spark needs minimal. Perhaps at power-down, turn excess flywheel energy over to a generator.
Stand…? A two-sided one raising the rear tire? or a side-one, breaking symmetry?
Full rounded hubs covering the entirety of both wheels so nothing comes into the gears or front brake pad. Rounded especially on front wheel so corners taken on bike don't create a sail effect.
Full torque has to be enough to leave everyone in the dust. For this reason weight must be displaced towards the front and the rider leaning full-forward.
Aerodynamic at both front and back to slipstream, unnoticeable by the air.
Panels on each side of the bike to show where its been (country stickers…??).
Braking-force recovery systems based on electrical storage may be viable. A mechanical flywheel heavy enough to be useful will consume any benefit of its operation in the inefficiencies of lugging around all that weight. It will destroy the handling of the motorcycle, too.
The future of alternative motorcycle power is almost certainly electrical. The monster zero-RPM torque of an electric motor makes for crazy acceleration, and its relative efficiency and compact size makes electric power highly effective. See, for example, http://www.zeromotorcycles.com/eu/ My next motorcycle, when my Honda VFR800 wears out, will almost certainly be electric.
The "the constant inertial loss made by the mass of the pistons having to change to the opposite direction on each cycle" doesn't exist. You could use the same argument against rotating engines...any given part of a rotating object reverses direction with each half-rotation. Big expensive turbines can gain efficiency by using high combustion temperatures and expansion ratios, special cooling systems, exotic materials, many stages, having high volume to surface area ratios, etc. Tiny motorcycle turbines aren't going to be as efficient, and may well be less efficient than an equivalent sized piston engine. Turbines also store a substantial amount of energy in the rotating parts, making them slower to increase or decrease power output, and bringing up the next point...
For flywheel storage, a heavy material like uranium is exactly the opposite of what you want. You don't want to maximize momentum, you want to maximize kinetic energy. Both are directly proportional to mass, but energy is proportional to the square of the rotation rate...you want something with the highest strength to weight ratio you can get, spinning as fast as possible. Energy storage flywheels are often made of wound fiber composites, or in one recent approach, simply a loop of bundled fibers, and are actually a relatively dense way to store energy. I wouldn't consider them ideal for a motorcycle, though.
Let me get this straight.
A host of Professional engineers -- a title requiring both intensive training and years of real-world experience (so any lies they hear in engineering school are disabused by the laws of physics themselves), have developed a series of over-complicated turbine engines, while you have a patent pending design for a CFC engine that is much simpler, for the purpose of powering a motorcycle? And those who disagree simply don't get it, and have been programmed by the NovusOrdoSeclorum??
So far, you may be the one-in-a-million genius who can revolutionize the industry. That being said, it's much more likely that you simply don't know what you're talking about, just by the law of averages. If you are that one-in-a-million shot, the only way you're going to be taken seriously is to RaceTheDamnedCar...er...bike.
And it's not like the Powers That Be can stop you. If you can scrape up a few thousand USD, you can likely find a machine shop that can build your parts to spec (unless you need some exotic materials; certainly, regular turbines often do for their vanes). Even if there is a Great Otto Cycle Conspiracy (or Otto/Diesel/Turbine Cycle conspiracy), your average machine shop hasn't been co-opted into it.
And after simplifying the motor, you want to re-complicate matters by putting a second one in, complete with the completely unnecessary risk of flaming death. And then you want to feed it leaded gasoline? Why, for added octane? There are friendlier ways to raise the octane these days. And a uranium flywheel? Oh, but you won't need a transmission. What does the torque vs. RPM curve look like on the CFC?
And then you go on about inertial losses, proving that you have no clue what you're talking about and dropping out of the one-in-a-million category.
You're starting to sound like TopMind.
Okay Mr. "Engineer", you had me up to the point where you joined the choir above about dismissing inertial losses. The inertial loss, mind you will be mainly of the mass of the piston, not the whole crank assembly which is made (unnecessarily) more massive by having to need counter-weights on the opposite end of the piston crank. Show me an artificially-weighted piston (so that the truth of what I'm saying will be more observable) that maintains its spin (i.e. rotational momentum) after you remove power that compares to a equally-massed wheel. Go on. I dare you. Thanks for listening in any case. Then help fund me so I can get the heck out of poverty. -- MarkJanssen
{Look at the Earth and moon. They haven't stopped turning yet. Your "inertial losses" do not exist. (If you stretch, you could consider radiation of gravitational waves to be such a loss, but it's clearly not an issue for small engines. There's no other physical basis for a loss.)}
Wait, pistons have rotational momentum? I must have missed that class. Last I checked, pistons travel in a straight line.
A piston in a cylinder will slow down much faster than a free-spinning wheel, but that's due to friction. The piston is in a tight metal sleeve (cylinder) and lightly scraping against it, converting kinetic energy into waste heat. Make a wheel slide against a tight metal sleeve, it will also slow down right quick. That's how brakes work - squeezing a spinning wheel or disc against something. The kinetic energy converts into waste heat, making the brakes hot. You can even gather your own SelfStandingEvidence; see how hot your brakes get after heavy braking, like stopping from highway speeds. Don't touch it with your bare hands; just hold them an inch or two away and see. --RobMandeville
[Yes, pistons have angular momentum. Everything physical has angular momentum. You are otherwise correct though.]
Do this experiment then, don't put the piston in a tight metal sleeve. Put it a loose one. Make it heavy, so that if your theory is correct you won't notice any problem (because your claim is that there's no inertial loss in switching directions). But if my statement is correct you will notice it slow down for equal mass and roughly equal radius'd wheel. There, atomic bonds are in your favor providing extra centrifugal (i.e. smooth and continuous rather than discrete) support.
<Can you show mathematically that there is an inertial loss in a crank-mounted piston switching directions? (Hint: you can't, because there isn't one.) See http://www.physicsforums.com/showthread.php?t=134636 >
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