Ultralight Diesel Fuel Burning Small Wankel?

[a64pilot]

Trust me, if Toyota pioneered VVT to emulate an Atkinson cycle, they would have patented it, and they didn't.
I know VVT is being used to emulate the Atkinson cycle by many manufacturers, that link lists them.

What Toyota did that was brilliant with the Prius and it's PSD (power spit device) was in how it is being operated, they didn't invent any of it, but they did perfect it, especially the software.
The next big step that I expect is a world digital topo map so that the computer can know to use the battery to climb a hill, knowing it can get a lot of the energy back with regenerative braking on the downhill side.
If your interested there is a site, Priuschat.com real similar to this site, you have to do a lot of reading but occasionally Toyota Engineers log in and explain things.

There are if I remember correctly seven different operating modes of the Prius, one of them jokingly called the Heretical mode, where the car generates electricity to drive the electric motors, even though that is less efficient than using the mechanical power directly. I theorize that it goes into heretical mode when efficiency wise it would be outside of the possible gear ratio that is achievable.

See Prius usually operates at full throttle, but draws the RPM down to the HP point that is desired, low RPM operation is less friction and less pumping losses, especially if there is zero intake vacuum.

When you put it into "gear" it creeps, cause drivers expect a car to move if its in gear, there is no other reason for that, also when you release the accelerator it slows down with regenerative braking, because people don't expect a car to coast with your foot off of the accelerator, even though not creeping and coating would be more efficient.
The brake pedal isn't even connected to the brake hydraulics, but to a "stroke simulator" car is decelerated first by regenerative braking and if decel is in excess of what can be done that way then regular dish brakes are called into play, but the driver never feels the transition, well once you know what is going on, you can feel the transition at about 5 mph as regen quits about then and it shift to regular brakes.
Properly driven a Prius will never need brake pads, ever.

[a64pilot]

GM will probably make a mes of it as their marketing is a joke and has always been, but the Volt is by design likely superior to a Prius, but what makes the Prius so great is driving wise it's transparent, exactly the same as every other car, put gas in it and drive, that and the build quality, most seem to be trouble free.
I think and could be wrong, but the Prius is only built in Japan, and is the only Toyota you can buy in the US that is?
Probably old data.

[ThresherMan]

The diesel outboard looks like a good way to eliminate the bother and danger of carrying gasoline on board, but a winch to bring in on board is a must. Heavy rascals, even the 4 & 6 hp models, aren't they?

[a64pilot]

Dock, if your interested read this, there was a much better post from what I believe to be a Toyota Engineer, but I can't find it.

https://priuschat.com/threads/the-fi...eration.12919/

[a64pilot]

Originally Posted by ThresherMan

Heavy rascals, even the 4 & 6 hp models, aren't they?

There in lies the problem with Diesels, however I believe that common rail will improve the power to weight ratio

[Dockhead]

Originally Posted by a64pilot

Trust me, if Toyota pioneered VVT to emulate an Atkinson cycle, they would have patented it, and they didn't.
I know VVT is being used to emulate the Atkinson cycle by many manufacturers, that link lists them.

What Toyota did that was brilliant with the Prius and it's PSD (power spit device) was in how it is being operated, they didn't invent any of it, but they did perfect it, especially the software.
The next big step that I expect is a world digital topo map so that the computer can know to use the battery to climb a hill, knowing it can get a lot of the energy back with regenerative braking on the downhill side.
If your interested there is a site, Priuschat.com real similar to this site, you have to do a lot of reading but occasionally Toyota Engineers log in and explain things.

There are if I remember correctly seven different operating modes of the Prius, one of them jokingly called the Heretical mode, where the car generates electricity to drive the electric motors, even though that is less efficient than using the mechanical power directly. I theorize that it goes into heretical mode when efficiency wise it would be outside of the possible gear ratio that is achievable.

See Prius usually operates at full throttle, but draws the RPM down to the HP point that is desired, low RPM operation is less friction and less pumping losses, especially if there is zero intake vacuum.

When you put it into "gear" it creeps, cause drivers expect a car to move if its in gear, there is no other reason for that, also when you release the accelerator it slows down with regenerative braking, because people don't expect a car to coast with your foot off of the accelerator, even though not creeping and coating would be more efficient.
The brake pedal isn't even connected to the brake hydraulics, but to a "stroke simulator" car is decelerated first by regenerative braking and if decel is in excess of what can be done that way then regular dish brakes are called into play, but the driver never feels the transition, well once you know what is going on, you can feel the transition at about 5 mph as regen quits about then and it shift to regular brakes.
Properly driven a Prius will never need brake pads, ever.

Well, whoever invented what, no one can argue that the Prius is a fabulously complex device, packed with innovative technology, applied in completely new ways. It is a real engineering tour de force.

And much of the public looks at the sleek Tesla bodywork, and thinks stuffing in a big battery is a technological achievement Of course one does have to admit that this is the very definition of great marketing.

I'm just looking forward to the next generation of hybrids. I am intrigued by the idea of a series hybrid (which would be simpler, actually, since it only needs a golf cart drive train) with a super efficient, super compact generator. Possibly something like this Liquid Piston engine could be a basis. And some of the tech might trickle down to us, eventually.


The other fabulous thing will be self-driving cars. Have to give credit to Tesla there for some actual innovation (for a change).

[Wayfarer1008]

Diesel burning wankel engines have been around for a while and are commonly used in the refrigeration units on large trucks and shipping containers to power the refrigerant power systems. I have no idea why the wankel engines are not more common but I believe there is are fuel efficiency and emission issues that shelved the technology.

Where technology has gone over the top is with Micro-Turbine technology. A micro turbine with impellers the size of the palm of your hand as a co-gen unit can power a small hotel complex. Capstone has developed a version that actually runs low emission busses using natural gas but can run on Diesel fuel by simply changing out the jetting in the motor. I know that micro-turbine systems are used in the commercial marine business but I have yet to hear of the technology finding its way into the recreational market.

As for fuel efficiencies Diesel fuel contains 1/3 more burnable carbon than a gasoline and in so doing uses 1/3 less fuel to produce the equivalent amount energy. This make Diesel engines up to 1/3 more fuel efficient with the resulting gain in mileage. These numbers are even more a skewed when you take in the addition of Alcohol to gasoline with its low BTU content being added to gasoline. Alcohol added to Gasoline drops your mileage on the whole by as much as 15%. This also means that unlike what is advertised you are actually putting out more emissions than if you burned just Gasoline itself.

[a64pilot]

On the Hybrid thing, I believe the Russians in the 70's built Hybrid city buses, with little Diesel engines running at their peak efficiency running a generator, 15 or 20 HP I think, but anyway the bus would pull make 100 HP to get going out of the battery bank, then coast for awhile to a stop and sit to load and unload, the whole time the bank was being recharged by a steady state Diesel running at peak efficiency.
I believe they got some significant fuel savings, like ran the bus off of 1/3 the fuel. Bus only suitable for stop and go city driving too, max sustainable speed was something like 30 mph or maybe less.

Take a Tesla, cut the battery bank in half, size the electric engine for realistic performance by normal people and install a small, very efficient ICE generator.
You have a Chevy Volt!
I believe the Prius is genius, but I also believe its an excellent first step towards something even better, question is, can the grid handle electric propulsion?
Possible next step is to use the tens of thousands of Hybrid electric vehicles as an enormous storage system for the grid, maybe.

[SV Bacchus]

Originally Posted by Wayfarer1008

I have no idea why the wankel engines are not more common but I believe there is are fuel efficiency and emission issues that shelved the technology.

Didn't Wankel have issues with the combustion seals and part of the reason for their "setback" in the automotive world? Did they ever get around that?

[roland stockham]

I have a brilliant dingy engine that runs on pure vegetable matter, is fully self repairing, no exhaust pollution, can be made with renewable resources and simple hand tools and costs next to nothing to buy or use. They are called awes or paddles. All they require is that you are prepaired to allow the pace of your life to slow down a little, but then you are living a cruising life in order to do that aren't you?

[Wayfarer1008]

Dock Head !
A little history on the Prius Cars
The Toyota Prius was developed as a low emission commuter car strictly for the California market to take advantage of a new law allowing low emission cars to use the commuter lanes on California roads without having to do ride share.
Considering 1/3 of all cars sold in North America are sold in California it was a big potential market and worth the risk if the car failed. At first Toyota lost money on every car they built but the ground swelling of demand turned them into being profitable and the cars were released to the rest of the U.S. Even Toyota has pointed out the Prius is a great car if you spend your time driving in stop and go traffic but if you most of he time on an open road you are better off with a non-hybrid.
Toyota has been playing with a diesel hybrid for the non-US market that is super efficient but is not ready to release it. Take a Prius and add 1/3 better mileage to it and you get the idea.

[Wayfarer1008]

I believe the seal issue was resolved a long time ago. I know Mazda is getting ready to release a new Wankel powered car next year and the last model they built had no real mechanical issues.

[a64pilot]

Originally Posted by Wayfarer1008

Dock Head !
. Even Toyota has pointed out the Prius is a great car if you spend your time driving in stop and go traffic but if you most of he time on an open road you are better off with a non-hybrid.

I'll leave all the rest of that alone, but this I will address as I too used to think that, until I got a Prius, and found out what is called by the Prius crowd as the rule of 60.
That is a Prius at a steady state of 60 MPH will return a mileage of 60 MPG, flat ground, no wind.
There may be a few four door 3,000 lb automobiles that will do this, but I don't know of any.

[a64pilot]

Originally Posted by Wayfarer1008

I believe the seal issue was resolved a long time ago. I know Mazda is getting ready to release a new Wankel powered car next year and the last model they built had no real mechanical issues.

I believe if I'm not mistaken that Mazda with their performance branch Mazdaspeed is the only Japanese manufacturer to win the 24 hours at Le Mans, and they did it in a Wankel.
Wankel's pollute and use too much fuel, but can be made very powerful and will run for a very long time, the Apex seals being about the only wear there is.

[buzzstar]

Exotica and development are the words that apply to this thread so far. I think it is great, only if the glorified golf cart type comments are ignored along with who gets credit for what. BUT, while on exotica, and less development for boaters, why not Sterling cycle developments? Frankly, I am happy as all get out that these things, Atkinson, Wankel, diesel outboard, and even Stirling (can't recall if it is with an "e" or an "i" so I used both), etc. Keeps my old mind busy.