Mazda sticks with rotary power

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The Abrams already uses a turbine engine (rotary... sort of) which is far superior, especially when you factor in electric hybrid systems.

Turbines would be sweet for cars but they have two big problems. 1: Big as hell. 2: Hot as hell.
Yes, it does indeed use a turbine engine. A 1500 hp Honeywell AGT1500 gas turbine. The rotary APU is to power the tank's systems while the turbine is shut down to save fuel. Turbines guzzle fuel, but make tremendous power for that fuel they do guzzle. Turbines actually have the best power to weight ratios of any combustion based engine short of a pure rocket motor. And yes, they can easily be made small enough for even a gokart, as micro turbines are common in the r/c aircraft world.
As far as the exhaust temp issue, it can be fixed with a few clever tricks...
Oh, and rotaries are somewhat common in r/c planes, due to their power to weight ratio. They tend to be more costly than a similar power piston engine though.
 
The Abrams already uses a turbine engine (rotary... sort of) which is far superior, especially when you factor in electric hybrid systems.

Turbines would be sweet for cars but they have two big problems. 1: Big as hell. 2: Hot as hell.

It's the turbine, really, that invalidates the roatry as a hybrid range extender. Micro-turbines are being looked at as range extenders, and those are near-omnivorous and have the same simplicity and packaging benefits as rotaries.

This is not to mention piston-engine range extenders. With companies spending billions on developing terrific new triples and twins for use in small cars, there's a wide pool of range-extenders to choose from that are already emissions-compliant, compact in packaging and have the added bonus of the ease of maintenance that comes from being shared across a wide range of products.
 
Also, the problem with running a rotary at 2000rpm in a range extender is that you probably won't have the power density to accelerate hard through an electric motor. That's why the Accord Hybrid's Earth **** engine goes to peak HP-output 6500rpms during hard acceleration.
The Accord's engine is run at 6500 rpm because it doesn't have the low-down grunt to spin a geared-up generator. Think of it like how diesel locomotives work: tremendous torque, and when you ask for more power from the generator the brushes clamp down creating more current and causing more drag and you simply throttle up the engine a bit because it has the torque to maintain rpm. They don't even use storage batteries to draw from in the mean time.

A rotary range-extended hybrid would most likely have a battery system like the Volt. The engine would keep the batteries charged, etc. Even without a battery system all you have to do is port the rotary to make maximum torque at 2000 rpm, then it'll have the power to churn a geared-up generator under high load.

As for turbines, I think the biggest problems with using them in cars would be quelling the noise and exhaust blast. Even tiny ones move a lot of air and make even more noise.

But I think turbines are kind of a dumb idea. Jet fuel is more highly refined and considerably more expensive than diesel and if you were to burn diesel in a turbine it would run very dirty. Plus, turbines in general run rather inefficiently at low altitudes which is where cars operate.
 
This is what worries me:



The RX-7 peaked at around 50,000 units in 1986. Even if it was comparably efficient, powerful, and all else equal to a piston engine (which, actually, isn't really the point) I doubt they could move more than 100,000 units. Consider the sales of the Scion FR-S. It is being considered by most to be a sales hit, and it's shifting a bit less than 3,000 units per month, optimally. Do the math, and that's less than 36,000 cars a year. Not even Ford is moving more than 100,000 Mustangs a year. The fact that this new Mazda president won't consider a car that sells less than 100,000 a year is very worrisome. You have to balance brand identity/character with production & sales output, if you don't have the former, you will lose the latter. Mazda has never, ever been a volume seller, and they are better for it. While it is disappointing that the RX-7 won't be returning soon, it bothers me more that Mazda has taken up this business approach.

Also too, the MX-5 achieves nowhere near 100,000 annual sales (try just a shade over 6,000), where does this new philosophy leave the flagship sports car?

I don't like where this is going.
100,00 units means 100,00 engines. Not necessarily 100,000 cars.
 
I haven't read the thread so it's possible that this information is already in here. A local Mazda dealer told me today that Mazda is developing a very high pressure gasoline engine with the same technology as a diesel engine => self-ignition. This engine will be even more economical than a diesel.

I don't know the correct word so I'll use this: self-ignition.
 
I haven't read the thread so it's possible that this information is already in here. A local Mazda dealer told me today that Mazda is developing a very high pressure gasoline engine with the same technology as a diesel engine => self-ignition. This engine will be even more economical than a diesel.

I don't know the correct word so I'll use this: self-ignition.
Is it a rotary?
 
Ok cause this is the Rotary thread, just FYI. ;)
Yes but it is also a Mazda thread. And my post is also about a Mazda engine which could be a rotary engine. ;)


This is off topic but I just found out that Hyundai is also developing such a gasoline engine.

It's called: GDIC, or Gasoline Direct-Injection Compression.
 
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Some random person's idea of that they think it should look like. Remember that guys. That render is in no way official...
 
IT LIVES

IMG_5775-sm.jpg
 
Yes, that came about in December. Cool little thing. It's actually farther up this page.....

Here's a cool video I saw a little while ago on it.

 
Mazda "confirms" a new RX
Motoring
we've reported, it's suggested that Mazda is planning the reveal of an all-new RX-7 rotary coupe in 2017, to celebrate the 50th anniversary of the debut of its first rotary model — the Cosmo Sports of 1967.

But there have also been rumours that Mazda will then launch a second rotary model – dubbed the RX-9 — in 2020 to celebrate Mazda’s 100th anniversary.

We can now confirm that Mazda does have two special projects on the table — one for 2017 and another for 2020 – but it appears they will both revolve around the same rotary model, the reveal and launch of which will be spread over a four-year period.

“We want to surprise everyone in 2017 with something special to celebrate the birth of rotary," a senior Mazda executive told us.

"Then, to celebrate the company’s 100th birthday, we want to take it to another level in 2020," he added, confirming separate celebrations for both anniversaries.

From what we're hearing, Mazda will not launch two rotary cars, but stagger the reveal of concept and production versions over four years – not unlike Nissan did with its latest GT-R — to highlight its rotary heritage and generate maximum anticipation for its long-awaited rebirth.

It plans to kickstart the rotary dream in 2017 with the unveiling of a next-generation rotary concept car, and then realise that dream in 2020 with the reveal, launch and production of a belated replacement for the iconic RX-7, which we think will be called RX-9.

We know for sure that Mazda is developing a rotary engine for an RX-7 successor and has been doing so for the past decade. One source says that a Ferrari 550-resembling prototype surfaced briefly in 2004 on an RX-8 chassis.

“But that soon disappeared and the RX-7 project was put on hold until around 2006 when pretty much all of the company’s sports car engineers and designers were channelled into development of the new MX-5.”

Now that work on the fourth-generation MX-5 is done, Mazda has reallocated its senior R&D staff to the 'RX-7' rotary coupe project, since the relatively small Japanese car-maker only has the resources to build one sports car at a time.


We've heard that a prototype based on a reinforced rear-drive MX-5 platform has been testing at a racetrack in northern Japan and its signature rotary exhaust note was unmistakable. A couple of months earlier, a turbocharged RX-8-based mule was also spied testing in Japan.

In a world of 370kW-plus sports cars, our source tells us that Mazda is targeting around 335kW for its RX-7 successor. “But to get there with a rotary engine is not easy,” he tells us.

With current rotary technology, the most power that a naturally aspirated engine can generate is around 225kW, says our source. “To get to the targeted 335kW, some significant extra devices are necessary.”

Our source has revealed Mazda engineers are working on a two-stage turbo system that incorporates an “electric turbo assist” function that engages at low rpm, and a standard exhaust-driven turbo that cuts in at higher revs.

“Engineers will employ a capacitor (a unit that stores power and discharges it on demand) to beef up the rotary’s ‘instability’ at low rpm, and when boost pressure rises, a standard turbocharger will engage to keep the flow of power coming,” said our contact.

This arrangement, we are told, more than solves the three main problems of the outgoing RX-8 rotary; namely poor fuel economy and emissions, excessive oil use and weak mid-range torque.

Even better, Mazda's new rotary engine will produce prodigious power in a lightweight coupe that will tip the scales at around 1280kg. In addition to employing the next MX-5's latest construction methods, engineers are also experimenting with “several carbon-fibre parts” to reduce weight and boost performance.
Motoring
 
The entire article is prefaced by:


Basically, it's all ********.

Not really, they suggesting that they will be a new RX-7 cause ....
“We want to surprise everyone in 2017 with something special to celebrate the birth of rotary," a senior Mazda executive told us.

The rest of the article is based on the info they got from Mazda executive and rumours but it's not just rumors.
 
I will be extremely impressed if Mazda manages to make a production rotary capable of surviving emissions regulations.
 
Yeah, modern emissions are a bitch. As a part of a hybrid system, a rotary makes tons of sense. Combine it with a system like you see in the P1 or 918 and you've got yourself a serious technological model.

Keep in mind people that Mazda is the only company who has been seriously developing rotaries for the past 60 years. Internal combustion engines have been developed for over 100 by all companies, not just one. They have several thousands of years of combined development work whereas rotaries have about 60. There's a ton of life left in them, it just takes time and money.
 
What Mazda ought to do is develop a rotary engine with different rotor sizes. They should make a 3-rotor engine, and have them go up in size from tiny cruise rotor to big power rotor. Rotaries are more efficient at higher loads, so the idea is that as you need more power, each successive rotor is engaged for optimum efficiency. There's probably a limit to all of this due to frictional losses from the unfueled rotor assemblies. But even if they just tacked on a tiny cruise rotor to a regular 13b, it would be much better.

I don't think they want to engineer it for fear of battery/EV tech getting better though. I don't doubt that they could, but they might not have to as time goes on.
 
What Mazda ought to do is develop a rotary engine with different rotor sizes. They should make a 3-rotor engine, and have them go up in size from tiny cruise rotor to big power rotor. Rotaries are more efficient at higher loads, so the idea is that as you need more power, each successive rotor is engaged for optimum efficiency. There's probably a limit to all of this due to frictional losses from the unfueled rotor assemblies. But even if they just tacked on a tiny cruise rotor to a regular 13b, it would be much better.

I don't think they want to engineer it for fear of battery/EV tech getting better though. I don't doubt that they could, but they might not have to as time goes on.

I don't think such an engine could ever be dynamically balanced. A different diameter rotor will (as the rotation is eccentric) have different dynamic mass centers than a smaller rotor, and I don't think you could compensate for that with counterweights.
 
Why? Each rotor is balanced so shouldn't there be a zero moment about the axis?
 

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