I am on my third volt and love it. I think this layout of electric driving makes the most sense, more than the complicated and slow hybrids ( I know the new volts are sort of hybrids with a fairly complex drive system) but basically the ICE charges while the electric motors drive. I was thinking that a Wankel engine would be a goood choice for this car. You save space and weight so you could use a bigger battery and I think you would get around the wankels weak spots like the seals since the engine would run a lot less and also rubs much more evenly without the constant change in rpm you have in normal urban driving. Mazda is supposedly coming out with a wankel hybrid. I think it’s worth considering. Thanks.
Wankel engine
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Add emissions to the list of downsides as well. The rotary engine is definitely one of the more unusual pieces of technology and makes far more sense when it comes to creation and distribution of power since all the power is already in a rotational direction unlike a traditional piston/crankshaft. However the two-stroke like port design means a lot of unburned fuel gets washed out with the exhaust gases. Personally I'm surprised no manufacturers have mass marketed a diesel hybrid. Much more efficient and much more power at lower RPM than gasoline. If a small diesel can get 50mpg in a jetta, imagine what it could get when in a hybrid configuration?
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Did you know that the very first modern hybrid was designed and built with a Mazda rotary engine? Search for Victor Wouk, who is recorded as the "Father of Modern Hybrids" and read how he converted a 1972 Buick Skylark to become the first U.S. hybrid, but was frustrated when the EPA rejected his claims. His papers were read by the engineers at Toyota (Toyota did admit that they used Wouk's ideas) and the Prius was born. Wouk did buy a Toyota Prius later and was satisfied how it uses his ideas.
Here are some of the many links covering his work:
https://www.amazon.com/Victor-Wouk-Father-Hybrid-Choices/dp/0778746771
https://www.booksource.com/Products...ybrid-Car__9780778746645.aspx?FromSearch=True
https://www.mlive.com/opinion/flint/index.ssf/2009/02/victor_wouks_1972_buick_skylar.html
Unfortunately, he never established any patents over his ideas, and some Russian guy did.
Here are some of the many links covering his work:
https://www.amazon.com/Victor-Wouk-Father-Hybrid-Choices/dp/0778746771
https://www.booksource.com/Products...ybrid-Car__9780778746645.aspx?FromSearch=True
https://www.mlive.com/opinion/flint/index.ssf/2009/02/victor_wouks_1972_buick_skylar.html
Unfortunately, he never established any patents over his ideas, and some Russian guy did.
I had a Mazda RX2 at one point. I was going to put the engine in an Aztec 7 on VW pan. Moved before I got the project started. Mileage a downside. Emissions with direct injection/ECU who knows? Emissions and seal wear where always a problem. They are working on their next iteration.
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Whenever someone starts considering a Wankel engine for something I always have to wonder if they ever actually owned something with a Wankel in it. I so absolutely wanted that to be an up and coming technology, but it still needs some real advances in material technology to truly make it all it could be and that would make for one EXPENSIVE little engine!
I too have wondered why no diesel for the REX, especially given how the Volt uses the engine.
I too have wondered why no diesel for the REX, especially given how the Volt uses the engine.
For the 2019 Mazda 3 they have a new gasoline diesel like 2.0 liter engine that is said to increase fuel economy by 20%, over their already fuel efficient engine. This would be a good option for a plug in hybrid if they decided to make one. In the new Road & Track magazine for new 2019 cars they mention a 48 mpg estimated for the 2019 Mazda 3, which in that case would be the highest mpg for any non hybrid vehicle.....
I think there's a reason mazda's the only one to use rotary engines. They're really only good in very narrow operating conditions, as mentioned. Sure, that might be possible to be tuned for series EREV, but there are many downsides as well, also already mentioned.
But really, if it's going to be purely in a series arrangement (optimum efficiency the way a wankel runs) there are many better options, including development on free piston engines. If the goal is to just generate electricity, there's no need to generate a moving crankshaft output as in a traditional ICE. This also saves a ton of space as the magnets and coils of the generator could be embedded right into the single unit - as the piston moves back and forth it generates electricity just like those "shake light" flashlights.
If you're going with the volt design where the engine can actually move the vehicle, then it makes more sense to use a more traditional ICE.
But really, if it's going to be purely in a series arrangement (optimum efficiency the way a wankel runs) there are many better options, including development on free piston engines. If the goal is to just generate electricity, there's no need to generate a moving crankshaft output as in a traditional ICE. This also saves a ton of space as the magnets and coils of the generator could be embedded right into the single unit - as the piston moves back and forth it generates electricity just like those "shake light" flashlights.
If you're going with the volt design where the engine can actually move the vehicle, then it makes more sense to use a more traditional ICE.
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Totally forgot about "free piston" designs. Now I'm going down THAT rabbit hole online (LOL)
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It just needs the converters removed so the flames can be seen. They are perfectly fine as is if cared for properly.
Weight, maybe? Especially Gen 2's engine is REALLY efficient for gasoline, and they've managed to engineer all the complexity into things that the driver doesn't have to deal with and almost never go wrong, so if the power-to-fuel cost is pretty close, why not deal with a fuel that's easier to get?
Another reason might be customer acceptance. Most people have never owned a diesel, so that would be just one more unfamiliar thing about the car to make the customer move on. I personally have owned a diesel car, and while they look good on paper, there are some real-world issues with them that negatively impact the ownership experience to some extent, IMO.
The wankel engine had its moment in the auto industry. If it could have been improved for a profit it would have. I believe the wankel had issues that were far too costly to correct, or perhaps impossible.
Now forward to today and we have fuel efficient 4 cylinder gasoline engines that produce more horsepower than V8 engines did back in the good ole days all on 87 octane gas, as well as being twice as fuel efficient. Being 67 years old and I was there in the good ole days.
Longevity was another reason for the fail of the Wankel engine if I recall. Today, most engines easily go well over 100,000 miles, 200,000 miles no longer makes you the talk of the neighborhood.
Now forward to today and we have fuel efficient 4 cylinder gasoline engines that produce more horsepower than V8 engines did back in the good ole days all on 87 octane gas, as well as being twice as fuel efficient. Being 67 years old and I was there in the good ole days.
Longevity was another reason for the fail of the Wankel engine if I recall. Today, most engines easily go well over 100,000 miles, 200,000 miles no longer makes you the talk of the neighborhood.
I certainly hope you're right - But it will never be a money maker because they'll never sell enough of them to offset the substantial engineering costs. The Miata on the other hand has been an outstanding success
Don
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If you're looking for efficiency at burning fossil fuel a Wanker is not the way to go.
It's called: Brake specific fuel consumption (BSFC) is a measure of the fuel efficiency of any prime mover that burns fuel and produces rotational, or shaft power. https://en.wikipedia.org/wiki/Brake_specific_fuel_consumption
Look which gas burner tops the list. Unfortunately a Wanker is not on this list and I gave up looking.
They were compact and powerful for their weight but never fuel efficient.
It's called: Brake specific fuel consumption (BSFC) is a measure of the fuel efficiency of any prime mover that burns fuel and produces rotational, or shaft power. https://en.wikipedia.org/wiki/Brake_specific_fuel_consumption
Look which gas burner tops the list. Unfortunately a Wanker is not on this list and I gave up looking.
They were compact and powerful for their weight but never fuel efficient.
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Given how long gas sits in most Volts I suspect diesel would be problamatic. If you fill the tank in the summer with summer blend diesel it will gel in the winter in cold climates. Yes, you can warm it up but then you're using the primary fuel (electricty) to warm the backup fuel. Gasoline doesn't have this issue.
They are currently working on the next iteration according to Wiki. Light, small and vibration free make them good for a PHEV. efficiency and durability are less of a concern practically speaking because they are seldom used but of course people buy on the numbers, not on what the numbers actually mean to them.
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