Mazda to revive Wankel Rotary Engine...

[Czechvar]

This design has fascinated me since it came out...Now it’s going to be used in a new Mazda Electric car...

The Rotary Engine Is Coming Back - Mazda Revives the Rotary as an EV Range Extender

It seems like we've been waiting forever for Mazda to come out with a new rotary engine. The last production car to use the unique powerplant was the RX-8, and that car was cancelled all the way back in 2011. Now, the rotary engine is officially returning to Mazda's lineup—as a range extender for the automaker's first electric vehicles.

Mazda revealed the news today in a short press release announcing the launch of its first electric vehicle in 2020. One version will be purely electric, while the other will sport a rotary engine range extender that functions similarly to the gasoline engine in a BMW i3. Here's how Mazda justifies the use of a rotary engine in this application:

The rotary engine's small size and high power output make multiple electrification technology solutions possible via a shared packaging layout. Taking advantage of the rotary engine’s compatibility with gaseous fuels, the rotary-powered range extender is designed to also burn liquefied petroleum gas and provide a source of electricity in emergencies.
We've seen reports about the rotary returning as a range extender before, so this doesn't come as too much of a surprise. Mazda doesn't specify the body style, battery type, or driving range of its new electric vehicle, nor does it say whether this new model will be sold in the United States. The only thing we know for sure is that it'll have a rotary engine.

This new rotary-backed EV is the second part of Mazda's "Sustainable Zoom-Zoom 2030" initiative, where Mazda intends to pursue advanced drivetrains using a combination of efficient gas engines, alternative fuels and electric power. The first part, of course, is the automaker's ultra-efficient SkyActiv-X compression-ignition gasoline engine, first revealed in 2017.

Though it's not the RX-badged sports car we've been hoping Mazda would build, this news is a step in the right direction for rotary die-hards everywhere.

 

[Targets Guy]

Love seeing old things getting new life.

 

[venomballistics]

Interesting.
However the designs unavoidable oil consumption is why it keeps falling off the product line.
They burn oil. There's no getting around it.
As a result, they are difficult to get to conform to emissions standards

 

[LoboGunLeather]

The Mazda RX-7 was quite a development, back in the mid-1970's. The Wankel rotary engine design always fascinated me! Seemed to be a very efficient means for producing and transferring torque directly to the transmission.

I suspect that modern computer-controlled fuel injection and ignition systems will provide even better performance. Coupling the rotary engine to an electric generator should be about as efficient as anything to come along so far. Electric motor final drive should provide some impressive performance across a wide range of driving conditions.

Of course, the final analysis will depend on battery technology, on board capacity, and the relative efficiencies of power transfer from the IC engine to the electrical generator to the battery storage and on to the final drive components.

Maybe, just maybe, one day in the bright shining future there will be a hybrid or electric vehicle that makes economic sense without massive tax-payer funded subsidies. Maybe. Some day. Perhaps.

 

[4barrel]

Back in the early 70s I was driving a 283 hp 283 ci 1957 Chevrolet factory fuel injection in NHRA K stock. There was a Mazda with that motor running in a different class. When that car left the line it was the loudest weird noise I had heard at that time. That rotary motor was turning over 10000 rpm. No one at Interstate 20 Raceway had seen anything like it and didn't know what class to put it in.

 

[Kanewpadle]

Looks like nothing but trouble.

 

[oink]

Maybe they actually figured out the seal issue.

 

[GaryS]

Inefficient fuel utilization had more to do with the emissions than oil leaks. It also meant that Mazda couldn't meet fuel economy standards or emissions standards.

A lot has changed in 40 years, so maybe those problems have been solved.

Interesting.
However the designs unavoidable oil consumption is why it keeps falling off the product line.
They burn oil. There's no getting around it.
As a result, they are difficult to get to conform to emissions standards

 

[oink]

I don't think it was leaks. It was blow by of the main seal that made it work. But I'm not a mechanic although I did have interest back in the day. There was a motorcycle too but it wasn't a Mazda???

 

[ExcitableBoy]

The wankel motorcycle was a Van Veen, produced/marketed in/from the Netherlands. They had little sales success, but were kinda cool.

 

[Czechvar]

The wankel motorcycle was a Van Veen, produced/marketed in/from the Netherlands. They had little sales success, but were kinda cool.

Interesting...
OddBike: Van Veen OCR 1000 - Dutch Wankel Powered Superbike

[ame]https://m.youtube.com/watch?v=xu53wjxbJN4&t=55s[/ame]

 

[oink]

I believe the Hercules is the one I remember. I remember looking at two of them in a Triumph shop in Orlando 1976ish. Never rode one. I wanted a Bonniville. I was riding a little Honda 400X4 or maybe it was the Suzuki T-500. I don't remember.

 

[rwsmith]

That is fascinating......

The really ingenious design captivated me since the 60's. There were a couple of problems with these. The seals at the rotor edges were difficult from the start. Then they were improved, but I still think that they had problems. If they got that solved they've really done their work. Of course materials have come a long, long way. I'd like to know what they did. Probably ceramics, which are pretty amazing.

The second thing is that the high exhaust temperature was indicative of inefficient thermodynamics. I suppose with a turbocharger on the exhaust that could be improved.

Whatever, they've had enough experience now that they are surely more dependable. The seal problem was fixed by injecting oil into the cylinders. The advantages of the Wankel engine really make it a powerhouse with the problems eliminated.

Update: Wow, using it in an electric car is really exciting. I predict super success for it this time around.

 

[BLUEDOT37]

There was a motorcycle too but it wasn't a Mazda???

Suzuki made one too.

.

.
.

.

 

[steelslaver]

Its really all about thermal efficiency. The amount of heat possible from a volume of fuel and how much of it can the motor convert into usable energy. Most commercial gasoline engines are around 30%, A few highly developed designs hit about 40%. Diesels are usually better than gas motors in the thermal efficiency department.

A piston engine drives a piston down to stop then up to stop. Large number of moving parts that need energy to move, plus a lot of it is rotating mass. If they can developed a engine with less rotating mass and moving parts per HP generated they will have a more thermally efficient engine. Part of the emissions equation should be how much power is produced per quantity of emissions. Not just how much emissions in a volume of exhaust. If 2 engines produce the same volume of exhaust and one produces 2 times the usable HP at that volume, but, 50% more emissions than the 2nd it will still produce less emissions per actual work done.

Currently they check cars at idle and there is no real reason now for a car to idle. Electrics and electric hybrids don't.

 

[Breakaway500]

In 1974 my Dad bought a Mazda rotary powered truck. It was inexpensive,very smooth,quite powerful and got over 20mpg when most trucks were getting single digit mileage. He put over 200k miles on it before it finally rusted away. Never had the engine apart..original clutch and transmission..even with me treating it like it was a drag car. (sorry Dad..) The rotary in the last generation Mazda RX8 is a drivetrain well worth experiencing. SO smooth...with a very wide powerband,and no oil or emission problems. Because of all the bad press,the rotary has been a tough sell. I hope they revive it as the design is a good one.

 

[Muss Muggins]

Looks like nothing but trouble.

They’re difficult, to say the least. My daughter drives am RX8. The worst part, besides constantly checking the oil, is remembering that you can’t start it for just a few seconds, like to move it, and then shut it off. If you do, it floods, and the restart procedure is like building an oxygen generator for Apollo 13. It’s also an engine that needs to be stepped on and blown out regularly to keep the carbon deposits moving.

That latter is Daddy’s role . . .

 

[THE PILGRIM]

That motor caused a storm the first time it came to town!
Ford bought into Mazda just to get access to it.
Didn't take them long to figure out -
This Dog won't hunt!

 

[Redbert31]

We had an rx3 Mazda with the Wankel rotary engine in 1973. Man did that thing fly! We loved it. The rest of the car wasn't as cushy as the'71 LeMans we gave up to get it but it was fun to drive and my first taste of manual transmission ( not that much fun in Brooklyn) but it was a great experience overall. I'd try it again. I'll have to show the link to my hubby!![emoji106]

Sent from my XT1650 using Tapatalk

 

[LVSteve]

I can see how a rotary could work as a range extender for an electric vehicle.

1) It would be MUCH smoother than the 2, 3 or even 4-cylinder range extenders currently in use.

2) As it would likely run at a constant RPM and load, those conditions make engineering a solution to the seal issue much easier.

Wankels do have a basic issue with thermodynamic efficiency due to the strange shape and surface area of the combustion chamber. However, perhaps the reduction in friction means it can break even with a piston engine, at least for a range extender application.