Mazda Brought Back The Rotary Engine!
ฝัง
- เผยแพร่เมื่อ 16 ก.พ. 2023
- The Wankel Rotary Engine Is Back In Production Thanks To Mazda!
How Rotary Engines Work - • This 3D Printed Rotary...
Subscribe to Engineering Explained for more videos! - goo.gl/VZstk7
Recommended Books & Car Products - amzn.to/2BrekJm
EE Shirts! - bit.ly/2BHsiuo
From Mazda:
"With the discontinuation of the RX-8, Mazda ended mass-production of the rotary engine in June 2012. Today, some 10 years later, the rotary engine is making a comeback. This new rotary engine has been adapted to meet the needs of our times and is now being used to generate power rather than as a drive unit.
While the 13B Renesis engine used on the RX-8 was a 654 cm3 two-rotor engine, the MX-30 e-Skyactiv R-EV uses an 830 cm3 single rotor format for the rotary engine generator. With a 120 mm generating radius (R) and 76 mm rotor width, its compact size enables coaxial placement and integration with the electric motor, decelerator and generator to achieve a unit with an overall width of less than 840 mm that fits on the same body frame as the MX-30 BEV. We also successfully reduced the weight of the engine by over 15 kg by using aluminium for the side housing section of the engine structure instead of the iron used on the Renesis engine.
The main contributor to increasing fuel economy and reducing emissions on the MX-30 e-Skyactiv R-EV rotary engine was the use of direct fuel injection. When fuel is injected into the ports on a conventional rotary engine, a lot of the air-fuel mixture ends up at the back of the combustion chamber, not fully combusting and eventually being expelled as unburned gas. This has a negative effect on both fuel economy and engine output.
The rotary engine on the MX-30 e-Skyactiv R-EV uses direct fuel injection, making it possible to distribute the air-fuel mixture to the main combustion area and achieve more efficient combustion. Additionally, direct fuel injection atomises the fuel at the time of injection making it possible to sufficiently vaporise fuel even at lower temperatures. This also helps prevent the injection of excess fuel.
The engine also adopts an exhaust gas recirculation (EGR) system to improve fuel efficiency. Adding an EGR system that operates mostly at low rpm and low loads improves fuel economy by preventing cooling loss caused by rotary engine combustion chambers having a greater surface area than those of a reciprocating engine.
Apex seals are attached to the tip of each rotor to ensure the combustion chambers are airtight. For the MX-30 e-Skyactiv R-EV, we increased the width of these seals to 2.5 mm to improve wear resistance. We also changed the plating on the trochoid surface inside the housing to reduce wear and frictional resistance. For the sides of the housing, we use aluminium for the surface of the side housing and have added high velocity oxygen fuel coating to add a ceramic coating which also reduces wear and frictional resistance."
Related Videos:
Why The Rotary Engine Died - • 4 Reasons Why The Rota...
Mazda's Hydrogen Rotary Engine - • Mazda Built A Hydrogen...
References:
MX-30 Press Kit - eu.mazda-press.com/forms/logi...
RX-8 Press Kit - newsroom.mazda.com/en/cars/11...
BMW i3 Press Kit - www.bmwusanews.com/newsreleas...
VVT Study - doi.org/10.1016/S0360-5442(02...
Rotary Engine Intake Timing Study - doi.org/10.2298/TSCI180504058Z
Mazda Patent - patents.google.com/patent/US2...
Hat Tips:
Mazda VVT Patent - carbuzz.com/news/mazdas-new-r...
MX-30 R-EV Background - www.greencarreports.com/news/...
Engineering Explained is a participant in the Amazon Influencer Program.
Don't forget to check out my other pages below!
Instagram: / engineeringexplained
Facebook: / engineeringexplained
Twitter: / jasonfenske13
EE Extra: / @engineeringexplainede... - ยานยนต์และพาหนะ
**Common Question!** Why would a range extender (engine + generator) need to operate at different RPM?
Realistically, the option for a single RPM is there, and as stated in the video, there's likely an RPM that the engine spends the vast majority of its time at. There are reasons, however, why you might want to occasionally run at different RPM. For example:
1) Engine startup. This engine makes peak power at 4500 RPM. If peak power is needed to recharge the battery, you probably don't want to go straight there on a cold engine.
2) Battery charge rate. Batteries are able to charge faster at lower SOC (state of charge), vs higher SOC. This could mean at low battery, the engine output would be greater, and at higher battery SOC, the engine output drops because the max charge rate of the battery is lower.
3) If the engine is capable of high output, it likely exceeds the max charge rate of the battery. For example, the battery (relatively small vs dedicated EVs) is capable of 36 kW fast charging (it's a small battery so this is a normal number, despite sounding low). The rotary engine has a max output of 74 HP (55 kW), thus exceeding the max charge rate, so there are likely times where it runs at lower loads, and times it runs at higher loads, depending on the battery's SOC. So why does the rotary have more power than needed? At times, it is used to not only power the generator, but also to send more power to the driven wheels. If you ask for full torque (floor it), the battery and engine+generator are both sending current to the drive motor, giving you more power. In this state, it would make sense for the engine to be generating max power.
You mean the Wankel engine?
why not keep the same RPM and change the load?
Great explanation. This is exactly why I came to read through the comments! 🙂
Have you done a video comparing the efficiency of different engine types at a constant RPM? Mazda does like the rotary/Wankle, how does it compare to a piston, or turbine engine of similar size?
I am 45. Since I was a kid, every 10-15 years Mazda would "bring back the Wankel".
Gotta love Mazda’s resilience with keeping the rotary alive.
Absolutely, they even go so far to say that "rotarys are our thing" and that they would love to make a modern rotary sports car.
IMO, they should have killed it years ago and spent the money on technology with a future.
I hope any f1 engineers find intrest in developing rotary for mazda
It’s really the only thing that makes the cool IMO 🤣
It's not resilience, it's baiting suckers with candy sweetened with aspartame.
I had an 87 rx-7 and it's the least surprising thing in the world to read that a lot of the fuel went out the exhaust. You could stand behind it and see/smell it happening. It was my favorite car ever.
Anyone who ever replaced a burned out "thermal reactor" was well aware of unburned fuel/air mixture. There was a sheet of flame coming out of the rotor chamber into the thermal reactor three times on every full revolution. I loved my RX-4 Wagon it was a blast to drive. Fuel economy ha, ha, ha! I hope this new iteration works like a charm as I am now driving a RAV-4 Hybrid. I think hybrids will likely be the best long term solution since new power generating plants are not coming online fast enough to support a complete change over to EVs.
@@erictwickler4247 National Grid (UK's national electricity distributor) says it is completely confident it can supply all the EVs that are going to be driving around.
By the way, what's a 'thermal reactor'? I owned and drove an RX8 for years, and I've never heard of such a thing.
Had an RX-8 still miss it to this day. Nothing really like it. Maybe a Porche 911. Closest thing to it I've driven.
@@johnbb99 The thermal reactor is mounted just outside the exhaust ports. It oxidizes the unburned exhaust gas expelled from the engine to reduce the noxious components such as hydrocarbon and carbon monoxide. When the engine speed is high or during deceleration or full load running, the air control valve feeds fresh air from the air pump to the thermal reactor cooling air jacket to properly maintain the temperature of the reactor. The nonreturn valve which prevents backflow of exhaust gas from the reactor is attached at the air inlet of the reactor.
@@greggc8088 Its what we call a catalytic converter in the US.
You've mastered the art of explaining complicated technical subjects in a way anyone can understand. I love every minute of your videos.
Brilliant!
I believe Mazda has the right idea here. There is so much noise about EV range but extended EV range requires huge, expensive batteries. Better to have a smaller battery for commuting and the range extender for the few times a year people need to travel long distances.
The Mazda would be perfect for us as we only need long range a couple times a year for vacations.
The new 2023 Plug in 🔌Prius and this Mazda are on my short list of possibilities for my next vehicle.
That's very kind of you to say; it's absolutely the goal and I'm happy to hear you enjoy the videos!
@@EngineeringExplained Aloha can you review the updated Hyundai palisade calligraphy AWD please and thank you it's got a advanced V6 engine it can run on Atkinson cycle or Otta cycle
Spoken like someone that hasnt had to fix that junk over the last 30 + years. Let the designers fix them.. I wont touch them anymore. Find another job, and best you get off of You Tube. This is garbage.
Hard agree
Funny story: Many years ago I worked with a large team of engineers who were submitting analysis of car motors for the EPA. We wrote the study you mentioned 😁. Also your white board is concise and easier to read compared to the 10 or 12 we had in our office. Also, our paper found according to the current rotary engine schematics that Mazda provided at that time, we found so many issues with operation and inconsistencies with their EPA readings. I hope Mazda has found a better way this time. I'll remain skeptical for now
Yeah, how in the world could Mazda's rotary engines pass emissions standards even back then with no EGR and a significant amount of unburnt fuel exiting the engine??
Did they have a special cat that isn't bothered by heat and can burn all that fuel properly?
EDIT: Nathan M provides answers.
I didn’t laugh…
This looks like just another hoax, like the 16X, RX9, Mazda2 Demio R-RE and the RX Vision Coupe.
Yep,had 2 and constantly breaking down.wanker of a car
It acts like a 2 stroke engine the way it burns oil.
I appreciate how engineers can complicate simplicity
They need to keep their jobs /s
It takes a busload of them
Well…simplicity can be quite complicated🤷🏻♂️
It's more along the lines that reality is way more complicated than we typically perceive it to be.
@@lucasglowacki4683 and expensive
Fascinating how using the rotary as a hybrid actually improves the efficiency of the engine itself rather than just the efficiency of the overall system.
Very cool indeed.
These same technologies also apply to reciprocating engines which are inherently more efficient than the Wankel engine.
The concept in fact makes no sense, why would anyone want to dirty, noisy inefficient Wankel engine in their EV? It is completely incompatible with the whole green energy concept
@@sandervanderkammen9230maybe for smaller piston engines, besides they have valve timing so this novel approach doesn't really apply.
Also, I think you can just make that engine quiet. I doubt it would be any different than any other newish piston engine nowadays that are quite silent.
@@sandervanderkammen9230 this is not a hybrid, this is an EV used 95% the time in the city on pure electricity, but if you want to make a longer trip on the weekend, you can just turn on the REX. it has to be small and light, but efficiency is not the most important since used very rarely.
@tomo1168 It's a fundamentally flawed concept that all of the other automobile manufacturers have completely abandoned... as usual, Mazda is always the last to "get the memo"
@@sandervanderkammen9230 the technical concept is not flawed. for users driving 40km daily on pure EV charging every night cheap at home and doing 3-400km trips on almost every weekend is this concept perfect. but the number of this specific user type is too low for mazda to worth the R&D.
I have to say, this is EXACTLY what I've been saying the Wankel engine should be used for. A single-rotor range extender that can run at a more-or-less constant RPM takes the best advantage of all that the Wankel has to offer. Granted, I also believe Mazda should seriously consider throwing on a big-ass turbocharger because turbo lag doesn't matter on a range extender, but maybe in the future. Of course, I would love to see non-hybrid rotary car at some point, too, but I'll take my wins when I can. A range-extender is a great way to keep this fascinating technology alive, and I support Mazda 100%.
I dont think you can realistically turbo a single cylinder engine. I would imagine it's the same for a rotary.
@@mitchellsteindler it would be more akin to a 3 cylinder engine, I believe. 3 combustion chambers firing within one full rotation. Since the GR Corolla and GR Yaris from Toyota use turbocharged 3 cylinder engines, I would imagine it is absolutely doable on a single rotor Wankel engine.
@@SaxaphoneMan42 huh wow. Guess I should have paid more attention to how a rotary actually works
Exacty, a rotary engine for a range extender can be designed for a single, speed, a single, stable operating temperature, so the seals, the location of the intake and exhaust can be optimised for single speed.
Rob Dahm: but also...I built AWD 4-rotor turbo version of it with 1500 hp on the wheels at 35psi of boost :)
I love how when you really break down the complexities of a system like this, even if the device is boring or lame, once you understand the system, it suddenly becomes fascinating. That being said, I can't wait to see what Rob Dahm does with these rotors and housings haha
Couldn't agree more..
Hahaha exactly this. Mazda should be sending him a crate engine with a bow on top
To be honest, though... I think Rob Dahm might give Mazda engineers a run for their money when it comes to making a bomb proof rotary 😂
Haha exactly only rob is not going to want anything to do with this new rotary, the telling sign is that he still uses the old 13b rx7 rotary and straight up despises the renesis.
@@88Frank Honestly I wouldn't be shocked if they did. I'm sure there will be a few scrap pre-pro engines that need to be 'disposed of'
I love knowing that Mazda has not given up on the rotary. Mazda is a very special company, if you look at their history, people and passion in that company - they are so impressive.
That being said; this is definitely not the rotary 99% of us wanted.
🙃
absolutley correct!
No, but this could be a good use case for the rotary (any small rotary...not necessarily one using this patent). Compactness is great in a range extender. I hope it works out, as having any rotary in production will help its development and optimization.
They already made the rotary you wanted.
@@andoletube Yeah, but they don't need to make the rotary current enthusiast want. They need to make ones the market wants. That means long life, efficiency, and low emissions. Unfortunately, the rotary isn't great at any of those right now.
The rotary is great at many other things. If they can ever resolve the apex seal issues and optimize the rest, it would return to the market.
Maybe one path is as a range extender, where it operates over a far less challenging range and benefits from lower weight and size. Optimize it for that and maybe that experience will lead to further improvements for use as actual engine.
pointless.
There is not practical space saving as compared to phevs using otto cycle generators. And, the latter will provide better fuel economy.
The wankel is an interesting engineering exercise that belongs to history books
What an awesome video. I posted a comment concerning the added vibration of this (angular deceleration must be transferred into some (small) linear acceleration) but then I un-paused and you answered my question. I love how you anticipate what your viewers are thinking so well.
This is the second of your videos i've watched, and I'm absolutely blown away!! Subscribed, think i'm going to enjoy binge watching your previous videos!
Thanks for the clear and concise way you explain very complicated subjects!
Absolutely love Mazda's dedication to keeping the rotary alive and even improving it out in these times. I can't help but feel another rotary beast is on the cards, but we can only be hopeful
Unfortunately we will never see another rotary engine powered car due emission rules. They tried with the rx8 and with all the emission gear it's just no go good
Mazda is so awesome, they are the ones who go out of pattern line, building different engines
I'm hoping for another beasty Rotary-Driven car in the future. Should have more tech to hopefully 'meet' emissions (or just bloody lie about them, lol) and they better slap a turbo on it. :) Please Mazda
@@rotormotor13b there's one in the video you're watching, forehead
@@ThatHoodlum19 YES!!!
Instead of a double stack make it a QUAD STACK
MORE horses...
oh and it's gonna have to be rebuilt EVERY 5 MINUTES because the piece of crap literally breaks apart by existing....
Like you gotta realize it isn't being made for a good reason. It's not feasible technology unless you're rich and can afford to rebuild it and be fixing it all the darn time for those couple weeks you get to drive it in peace...
I love your enthusiasm, makes me feel comfortable in how much excitement I find myself enjoying when I quest down these rabbit holes.
I'm really appreciative of your content! You make engineering very interesting.
Honestly, I really love this idea, I drive a Chevy volt, so I’m obviously biased, but most trips are short electric trips. And so it works perfectly fine. You can make 4 plug-in hybrids with the same amount of batteries as 1 full EV with decent range. And the overall salts in more electrical miles driven..
1 ev and 3 ice versus 4 plugins results in total in 25 and 75% of miles driven electrically for same battery capacity:
1+3/4 =25% vs 0.75*4/4 = 75%
The one issue with plug-in hybrids is that you’re still lugging around an engine and this is where a Wankel makes a ton of sense.
It’s light and it’s simple, and it does still save you from lugging around the giant battery so in the end you’re winning out.
I honestly think for as long as we are battery constrained this is a fantastic option.
It's crazy to me how people love going to extremes. I've seen stuff about EV owners towing a trailer with a generator to charge their vehicle. Why? How can that possibly be better than a hybrid? It seems to me that hybrids are, have been, and will continue to be for the foreseeable future the best option.
The amount of joy I got from this video is substantial. I can't wait to see what Japan really brings to the EV market.
EVs are a scam. They are unsustainable to produce, because there is not enough cobalt to go around. Even if there is enough the mining is highly damaging to people and nature. The lithium cannot be extinguished once caught fire making these vehicles very dangerous in accidents. But hey, don't let me stop you from buying a usd 60.000,00 car that no mechanic can repair.
Not much unfortunately. They are like 15-20 years behind the world. For example hybrids made a lot of sense in the 90's and 00's, but they make no sense today. Currently batteries have enough capacity at an affordable price and the charging infrastructure is pretty good, so pure electric cars work just fine. And the problem with hybrids is you carry two powertrains, which in many ways combines their disadvantages. For example they need more maintenance than a gas car, more expensive, and if not used correctly they burn more gas.
Japan isn't bringing much to EVs. They're doubling down on hybrids and hydrogen.
The Koreans are doing well with EVs though, specifically Hyundai.
Another lunch? Because Korea ate theirs.
Japan will introduce a solid state battery that will be the biggest game changer in EV's
Just stumbled on this video and now I am hooked. this guy explains these concepts so well. Thank you fore this video :)
I been wondering for years, close to decades now, why rotarys aren't used in hybrids. Seems like a great pairing to me.
Because they are expensive to maintain.
despite being beautiful objects and fascinating machines, rotary engines are fundamentally limited by materials science and manufacturing costs. there isn't a single rotary engine out there that doesn't eat apex seals for breakfast, and machining the combustion chamber is much more complicated than boring the cylinders in a piston-cylinder engine.
Well...if used to power the vehicle and spinning at high rpms... yes. Don't think this is their point here. Japs (Toyota) are working on bringing out solid state batteries in their hybrids. This would be a game changer as you could get high mileage from small battery packs while keeping the vehicle weight at ICE levels. Rotary would make a lot of sense for such use.
there's a fundamental geometry problem, in that a long and thin combustion chamber spends more time heating the housing than producing power.
Very clever, I use a single rotor 13B in my aircraft, the 13B is well suited to aircraft as we don't have anywhere near the RPM variations that automobiles have. We are able to tune the intake runner to give us maximum volumetric efficiency at our desired RPM. In general we only have power variations on take off to cruise and then to landing, there are other times we might want to reduce or increase power but way less than an automobile.
That's awesome. Makes total sense. Rotaries and aircraft are a great match for sure!
The wankel was intended as an aircraft engine in WW2 already, but German bureaucracy and the illusion of a "small displacement" didn't give it a chance.
Wankels run like turbines, they are uber efficient as aircraft engines.
Id be terrified to have a rotary in an airplane. I know 6 people that owned rx7s with 13bs. They were almost never on the road. Constantly breaking down. One of them was just driving along normally and suddenly stopped running. No warning at all.
What happened was an apex seal broke, and the engine took those broken bits and dragged it around the housing destroying everything.
Rotaries are light and powerful but inefficient and fragile.
@@slickstrings because a road rotary changes manifold pressure and rpm constantly, this causes severe wear on apex and corner seals.
I fly an experimental racer with two 600hp rotaries. With a Time Between Overhaul of 3500 hours or 15 years whichever comes first. A normal Lycoming engine needs to be rebuilt every 2000 hours or 12 years, but 10 years seems to be the norm.
The engines are cheaper on parts, weigh less, more reliable compared to the aero engines whose tech dates from the 1920's, uses less oil, can't be shock cooled, if the engine does fail it does so gradually loosing power giving you more time to compensate, they use less fuel, have less vibration, has a higher thrust to weight ratio, turbos easier, less parts mean more time between inspection.
To drop a wankle in a car was a mistake from day 1. This machine was meant to be an aircraft engine from the start.
@@PrinceAlhorian as an av geek i admire that quite a lot.
A gas engine powering an electric motor is exactly what I was looking for. This kind of system has been used on trains and ships before. It’s very reliable and gets rid of things that cause trouble like the transmission.
Yeah... i would recommend you to rethink that "reliable" part.
It's far from being the same, because in locomotives and ships where it's used for a very long time, combustion engine produces all the power that electric motor needs at exactly the same time. Here you can't provide maximum power with just combustion engine and you have very advanced electronics and inverters to charge batteries or provide power directly to the motors.
One of the most reliable vehicles ever produced... the Honda Insight G1... uses a gasoline motor + brushless fixed magnet HV DC motor. Basically the opposite of what you described... it is still one of the simplest hybrids though. The only engines that are more reliable are heavy truck engines.... my G1 has 300k miles on it. And the parks showing the most wear is the suspension not the drivetrain.
The BMW i3 REx and Fiskar Karma are pure series hybrids (as you described). The Honda iMMD system (such as in an Accord Hybrid) and Mitsubishi Outlander PHEV run as series hybrids except in highway cruise, when they engage a fixed-ratio mechanical drive.
Honda makes amazing hybrids exactly as you describe
Crazy first time iv had one of your videos recommended in well over a year! Glad it was🎉
Excellent explainer - been waiting for details on this RE solution of theirs - its been known to be coming for a few years. This is why I like Mazdas so much. They think differently, with the driver and drive experience foremost.
I'm not at all disappointed by this, an extremely small two moving part engine that bolts to the side of an EV without adding much weight like a piston would and making this transitional tech usable is fabulous. Bring it on Mazda, just make a heady duty, small off road vehicle with this too and you'll have my custom very soon. Cheers EE.
A small opposed piston multi fuel engine would be 1000% better than this rotary and that is the sad part.
pointless.
There is not practical space saving as compared to phevs using otto cycle generators. And, the latter will provide better fuel economy.
The wankel is an interesting engineering exercise that belongs to history books
The wankel is a engine for those who actually love driving.
The space savings and smoothness of this engine are viable. If the ev uses the engine occasionally it may be saving power by not lugging around a heavier motor. Most prius owners brag about how little their engines run. Proving that those who can charge their car from home dont need to carry a full size engine. Additionally a rotary engine is smoother than a piston engine making it less noticeable when using it. Im sure mazda was able to get at least 35 mpg using it as a range extender for a premium SUV. Time will tell but it may be best to wait for more information.
Unfortunately the wankel even in its "optimized" range is still at best 25 MPG here. Its primary advantage is leaving more space for EV range and avoiding using gas as much as possible.
@@aaronmorgan2475
Their released estimates end up to be around 25 MPG. It still ain't great.
As a range extender, the rotary can be kept in its most efficient RPMs range - if not just its very best point. I always expected that, if Mazda were to bring it back, it would be as a compact, near vibration -free, constant speed power generator. It makes a lot of sense in that use.
This is EXACTLY on point. It can beat typical reciprocating (piston) engines on efficiency when optimised for static load. This is why they are so reliable and efficient in aircraft applications for example. A generator being another perfectly optimisable example.
Except Wankel engines don't last very long without having to be rebuilt. They are one of the least reliable engines ever made due to the inherent awful mechanical design.
@@DaroffApFire We hear the same old thing about improved apex seals bla,bla bla......
@@cathalsurfs I'm not completely convinced a rotary is better than piston as a generator. Pistons are hitting 40% nowadays. The only numbers Mazda has released is "20% better than 13b". Internet snooping suggests 13b is around 25 to 28%. 20% of that is at best 35%. that's ok for a gen 1 Prius in like, 1998.
I love your videos. You do the best job at breaking things down, so even guys like myself that aren't as familiar with rotary engines, can easily follow along and get a better grasp at what is going on.
Who would think that a white board and colored dry erase markers could do such an excellent job as a teaching aid? Lol!
Excellent presentation. Keep your energy-level up. Cheers!
This is exciting. I have owned 4 first-gen RX-7's (79, 81, 84, 85) and truly loved each of them! Loved the sound, driving feel, and look.
I hade a 83 & 87. The first gen was amazing. 2nd gen was cool but it was more fun in the first.
Lucky bugger
@YOU BLYAT Honestly, it killed me to have to sell my 84 first Gen when moving to Canada. It just was not cost effective at that point, and yeah it gets to -25 and even below -30 degrees with tons of snow here 😅 My Crosstrek is spectacular up here!
So many people have old great rx7 stories
'82 then '84GSL-SE.
Boss asked if I wanted the company car (911 Carrera) for the weekend - I said no.
A video about Mazda's new 3.3 I6 DIESEL would be interesting too, it's extremely efficient.
Nothing wrong with an efficient diesel-powered car!
@@nickvledder there is when it's the only option available
@@nickvledder efficient on the highway, but not elsewhere let's be honest. That's what DPFs are for.
@@nickvledder Well, maybe. Emission control is still a serious problem for cars and smaller light trucks, especially if the vehicle is just driven in town. Having to replace a $1300 (Rockauto price for our F350SD work trucks) DPF every few years is nobody's idea of a good plan. That is the primary reason our Fortune 100 electric company went to gasoline for anything under 18,000 GVWR in 2010.
Diesel makes sense in large trucks but not in light trucks or automobiles.
wtf I knew they had a new inline 6 but didn't know about dieselness. Mazda is having another big lump of weird innovation, I like it.
I applause Mazda's efforts of continued development and innovation with the ICE. One has to wonder if the both patents weren't designed specifically for this range extender, and the other patent with electric motor is foreshadowing a performance multi rotor powertrain. 🤔
Time will tell I guess 😊
I believe they had already applied for that patent a while ago with a very different set up, front wheels only motor powered and rear powered by motor and a triple rotary, with super capacitors charged from the rotary, via the rear drive motor.
I think the patents are designed purely as promotional material... it's not as if there was the risk of another major car maker copying any design that involves a Wankel engine!
(FTR, personally I actually like a lot what Mazda is doing here.)
The technique of speeding up or slowing down the rotor would be more difficult on a multi-rotor. Usually, a multi-rotor engines would have the rotors at different phase angles, therefore the ideal time to "speed up" the rotor would be different for different rotors! If you made all the rotors on the same phase, vibration would be increased.
No, because today we have Emissions Standards. And most of us don't want to top up the oil all the time. Mazda is circling the drain. Zoom Zoom is dead.
@@leftaroundabout Me too, I'm really thinking of picking one up as a commuting appliance to replace my Volt (while I can still get more than what I paid for it) and while I wait for Aptera to start production of my preorder. Plus I get to support rotary tech, they will only keep making them if spend our money on them.
This was a fantastic breakdown! Thank you!
that was honestly such a pleasure to watch!
I thought if the rotary or even piston engine was used purely as a generator then it would have a fixed RPM and therefore porting shape and valve timing are irrelevant
Yeah I really wished he addressed this. I don’t understand why the engine can’t just run at one rpm. There’s gotta be a reason
This is exactly my question. If you look at the Paris Dakar Audi E-Tron they use a DTM engine running SPECIFICALLY at the most efficient RPM.
load varies rpm varies, not as much as conventional, but still there.
I was wondering that as well. My best guess is that if you're out of battery and hit the accelerator, you'll need more power from the engine, which it could not provide at it's most efficient RPM, so it has to rev up. But if you're just cruising on the highway, you don't need a lot of power assist, so it can run at high load@low RPM
That's just my guess, though. I'd love to have EE answer this
Exactly my thought and my comment too.
I remember seeing an article about how great the rotary engine would be as a range extender for an electric drive train about 6 months ago. I wonder if the writer knew Mazda was planning on exactly that.
Since the REV version was afaik planned to start together with the BEV MX-30, yes the wirter probably knew that
I remember such articles from around the time Chevy announced the Volt, if not earlier.
I was always wondering why the rotary engine didn't become the norm for lawnmowers.
I assumed it was mainly a market dominance issue, because lawnmower engines have no performance ambitions and run at mostly constant speed, and reducing engine noise is an advantage there.
@@Dowlphin probably because they evolved from basic 2-stroke engines which gotta be much cheaper to produce then a rotary
Those articles have been around since like 2014
Great video!
I know that the Volt development team struggled with coming up with a good efficiency plan on their range extender. It was determined that the customer would not enjoy hearing the engine at some disjointed rpm from what the accelerator pedal was doing. Maybe this rotary version is dead quiet? It should vibrate less I would think.
This is a big issue with the Honda Accord Hybrid. I don't mind the disjointed RPM. It only takes about a week to get used to. But the Atkinson buzzy peak is where it operates most often. Optimizing for a single RPM is great for efficiency and should be done. But a single RPM should also be easy to optimize for low noise. Failure to do so, fails the entire design.
That's what the Volt consumer group didn't like. The disconnection between the peddle and the engine rpm.
Very awesome video. I was smiling the whole time you were explaining the video. God!!! I’m such a nerd but I love it. Thanks for all the info.
My uncle designed his own rotary and used it as a range extender in a electric Sunbeam alpine in the 70's... Finally the world catches up! For a range extender a rotary makes sense from a packaging standpoint, and by running it at fixed rpm, they can optimize engine performance. I don't see why they want all that other shenanigans.
I was about to say the same thing - in a generator, why do you need to vary anything? Just pick the most efficient RPM and design your generator around that number.
The load on the generator need not vary, since you are charging a battery with it. It's a known quantity that you have control over.
I was thinking the same but its mentioned that the engine will also directly power the drive motors 7:20 when needed so it would need to be variable to keep up with the direct demand of the drives.
This story is so incredible I almost not believe you. Like those kids in a sandbox making up stuff about their fathers or in an online debate where the strongest argument is always "my uncle works at Nintendo"
@@frozen-curmudgeon it says it can send power to the electric motor to power the wheels. In such a case it would mean that the battery is empty and can no longer power the motor, which means any extra electricity generated could just be used to charge the battery. Maybe they just don't want to run the rotary at max RPM all the time, and this just allows better efficiency when/if the battery is empty and more power is needed? Weird.
@@ldmtag My friend would tell me he had a dragon back home and I believed him.
*Mind Blown by all of this information*
Thank you so much for taking the time to explain this to all of us (as always).
This is REALLY interesting stuff, man! Pulsing load on a generator to achieve variable valve timing on a Rotary engine. I never dreamed of such ingenious tomfoolery!🤯😂🤣😂
Good to see a Rotary in the works again though.🙂
Thanks for this one! I love rotary engines, and its cool to see a modern reincarnation.
Just another hoax like 16X, RX9, Mazda2 Demio RE and the RX Vision Coupe
@@sandervanderkammen9230 that's a very optimistic mindset you keep there.
Fascinating stuff and all credit to Mazda for wringing out the last drop but boy, it's quite a journey in the process of doing so! It will be interesting to see how it translates to a real world scenario and I'm guessing we'll soon be finding out.
Neat. I've like the idea of engine just generating electricity since I heard about how the Volt did it. Doing it with a light weight rotary engine makes a lot of sense.
Considering most people only need 50-100 mile range daily, but may need 300+ mile range once per month, BEV with gasoline range extenders makes the most sense. I loved the idea of the Chevy Volt. It's a shame it wasn't marketed well, and that few other manufacturers haven't also developed similar cars and trucks.
I would love an EV F-150 (or similar) with a 100 mile battery range and a range extender with of 300 miles. This would also allow for better towing capabilities.
@@stevk5181 The issue with range extended BEVs is the battery itself.
If you have a range extender option, that means a much smaller battery pack (otherwise the whole arragement makes no sense). If you actually use the car in it's EV mode most of the time, that means you'll be cycling thru battery a lot more. More cycles means more degradation and much quicker death (or unusable capacity) of the battery.
And you have a system that is a lot more complex (you basically have 2 different drivetrains + generator) and isn't all that much cheaper or lighter, as real world options indicate.
In reality, at least for most folks, it's either pure EVs (with a big enough battery) or a regular ICE. Everything inbetween rarely actually make sense.
@@hojnikb finally someone who gets it. PHEV is 🤦
@@hojnikb Then the solution to the charge cycle problem is to use a chemistry with more cycles, Tesla's NCA has about 500 charge cycles, why not use the far safer LiFePO4 with somewhere over 2000 cycles at the cost of half its range? That's still twice the overall lifespan and it saves them loads of money since there's no cobalt in it, thus its also far cleaner to manufacture. Its also got a thermal runaway temperature of 270'C instead of NCA's 150'C (and NMC's 210) and it doesn't change rather than dropping when its fully charged. Or better yet, go full in on efficient generators and use supercapacitors, its even cheaper and the vehicle's peak acceleration can be far higher too.
@@Avetho
Ok lets do some maths. Assuming MX-30 actually used LFP packs (which it likely doesn't) and the cycle life would be 2000.
Now the battery capacity in mx30 is 17.8kWh. A rought estimation of 20kWh/100km of power use on avarage would mean you could drive on battery alone around 178,000km before the battery dies (or drops below its usable capacity). That's just 110,000 miles. That isn't much.
In reality, Mazda likely uses NCA pack still which 1/4 of that or just 27,500 miles. That's low, no matter how you turn it.
Not to mention, that most PHEVs don't use cooling or heating of pack, much means even quicker degradation.
Even a cheap decent full EV will have at least 3x the capacity, along with active cooling/heating for extended lifecycle. Which means in theory, the pack will last A LOT longer than in a PHEV.
Do you see now how PHEV make little sense if you constantly drive on its battery?
Loving how excited you are explain this. That shows love for what you do.
I guess Mazda would love to create another car with rotary as a main power source - preferably as a mild hybrid. Maybe modified MX-30 range extender could be matched with small electric engine acting both as a variable intake timing as in the patent mentioned in the video and additional power source during acceleration. They seem to be experimenting in that way and would love to bring back rotaries, maybe as a halo sports car.
I've driven RX8 and fell in love with the sounds, high revs, linear power output and responsivity of a rotary. Personally I drive more conventional Mazda, Inline-4 B6ZE Miata.
saw a story a couple years back about the mitre turbine range extender. looked like a good idea at the time. APU’s in passenger jets have been using something similar for a long time.
Range extenders are a failed concept
APU's in passenger jets are super inefficient, and building a jet engine is expensive
I worked as technician for mazda during the renesis engine's life cycle. Key points about the rotary engine and its "incredible efficiences"
- modern piston engines have a thermal efficiency of about 40%. The rotary is 7%
- the unburned fuel mixture is so prevalent that the exhaust manifold on a rotary has the name thermal reactor, because most of the fuel being burned is done between the engine and catalytic converter.
This is why the rotary engine can never be high production, as manufacturers are restricted by emissions, and cost per kg of co2 output.
The fact that there's no good way to lubricate the seals on the rotor without putting oil in the combustion chamber is also an issue
@@DoRC Also, the main byproduct of the poor combustion is also carbon build up, which breaks the seals.
@@virus640 Yeah I wonder if they're just depending on low engine run time in this application too ameliorate the problem. I'm sure the new coatings are better but you can't get around the fact that those seals aren't lubricated
I will address the errors in (all) the above statements, in the context of this new and inevitable application by Mazda. Lubrication issues are negated with modern materials (ceramics). Carbon build up is negated, particularly at steady loads, leaner fuel mix and more complete burn and more efficient flame front propagation (direct injection). This also lends to massive increases in efficiency and it is well known (and accepted) in aviation circles that the rotary engine is superior in terms of reliability and fuel efficiency when operating at optimal (steady state loads) to piston counterparts. Therefor, the rotary is an ideal, lightweight, compact and overall better application for generators. I am guessing the OP is not working for Mazda any more.
Sounds like a total piece of crap to me lol
What I'd really like to see some company do is make a range boosting hybrid like this with the smallest possible engine where you can drive it at highway speed for a reasonable distance with either a failed battery pack or a failed engine. If the engine fails you have a full EV, if the pack fails you have a full gas car, and it would still be usable as a daily driver errand car until you can get the failed part fixed. This means you're insulated against engine parts shortages and battery pack shortages in the supply chain, replacing the part is then only needed in order to get your full range and power back. And since both the pack and the engine are smaller than with most cars, the repair bill shouldn't be too steep in either case.
I love the way you get to explain complicated subject and make them simple to understand. I would love to see your insight on the Liquid Piston rotary Engine.
Beware of LiquidPiston, it is a notorious vaporware investment scam
Its a joy to watch your videos
I'm really looking forward to your breakdown of the mazda straight 6 motors! I haven't seen anyone tackle the mechanical/drivetrain setup yet, and I'm SO curious!
I cannot think of anyone I would rather have explain this complicated concept to me.
A phenomenal instructor right down to the body movements to transition whiteboard spots. Kudos!
Man you always find a way to break it down to it's very last compound! A little KRS1 bar... had many RX-7's love the rotary engine. Wish they would of found a way before the FD3 gen got cancelled. Great info and keep up the good work.
Superb!.. Mazda racing got me thinking about kinetics as a design frame of thinking...thus capturing most energy with exceptions.
Lots of big things this year for Mazda, can't wait to be racing them and seeing what else they release for us.
Canceled, just another clickbait hoax
Great explanation. I initially thought it was going to be similar to the Yamaha "Power Valve" used in their LC two-strokes (which allows for intake period variation into the crankcase). However, this is much more clever! Thanks.
Good luck on your future videos
I was waiting for this one as soon as I heard about the return, I did some research but couldn't really pin down why to use a rotary. I am going to watch the video now and hope you can actually explain the why.
Of all the cars created I always loved the rotary engine because of it's uniqueness, happy to see this come back!
Would love to see your take on the new Liquid Piston engine. Essentially an inversed rotary engine. Keep the great vids coming!
Right? Stationary seals, equally distributed heat across the engine, combustion from 3 angles instead of one, and a LOT lighter
I've seen those promotional videos and wondered how much of it was true. They seemed light on relevant facts.
Another great video from you! Many thanks! I would like your analysis of the LiquidPiston rotary. Cheers!
Thanks for the breakdown!
While I am kinda disappointed that it's not going to be a fire breathing beast, I feel this is a great use for their rotary engines, and maybe somewhere down the road somebody will get enough spare parts together to make a 4 rotor direct injection custom do-hickey that spits fireballs and shreds tires.
If you are looking for a direct injection 4 rotor that spits fireballs and shreds tires, then check out Rob Dahm he does this exact thing today and its quite amazing.
Wow! I didn't remember the last time I saw Jason so excited as in this video about a new engine! I like how he can transmit those huge amounts of enthusiasm into you hahhahha
He's happiest at his whiteboard.
Always glad to see some rotary news 🤘
Very kind, thank you!!
Wow, fascinating, and delivered so well!
I'm a nissan guy. Always loved mazda. Right now I'm extremely satisfied and impressed. I want one of those rotaries.
My first car in highschool was a RX8 so this engine always gets my attention. Thanks for the breakdown of the patents!!
I'm sorry.
@Alister McCallum I didn't own it long enough to have problems. It was sub 50k miles when sold. I wouldn't be surprised if it was in the junk yard by 80k based on reputation.
Crazy that it’s able to modulate load and torque that finely thousands of times per minute. For something incredibly light I can see but manipulating the rotor so quickly seems like a quite a feat to overcome. Hopefully it works well for them and super excited to see a range extender let alone one with a rotary!
I was thinking the same thing. Also seems like all that pulsed load would result in vibrations that would increase wear and decrease life of the motor. Even if the pulsing is isolated from the passenger compartment.
TBF ECUs already do hundreds of calculations per second for things like direct fuel injection timings, valve timing, knock sensing.
@@apostolakisl Would the pulsed load not be effectively the same as what a main bearing in a crankshaft of a piston engine goes through?
@@Appletank8 And a modern inverter/motor controller can do a per-cycle calculation to regulate torque. This is one reason EVs have such good traction control, they can literally change torque request in a single motor rotation.
Yeah, I'm thinking it can't be exactly as described. I don't know the moment of inertia to do exact calculations, but in order to change the RPM of the motor by any significant amount during a single intake period (a millisecond or two), it would require intense torque, like that of a train motor or cruise ship engine.
Excellent Explanation! Thank you!
Thank you for the information, Great video.
So fun!! Thanks for bringing back memories. "... piston engine goes boing-boing-boing but the Mazda goes hmmm". Mazda has always wanted to be different and this idea is very clever. Note: Regarding option 1 & 2, in most cases, generators and motors are the same thing. You can make a motor act like a generator and make a generator act like a motor so, they could even use the motor as an active assist if they direct power into it rather than out of it. I am not saying they will do, only that it is technically feasible. The challenge is that the electronics around a motor and generator are different and so adding the electronics to direct power into the generator to cause it to act like a motor would come at a cost and it would need to be worth it.
Keeping the rotary engine alive even just as a compact high-power (for the size) generator in an EV is to be applauded. This sounds like a good application of Mazda's expertise, I hope it works out well for them.
Respect to mazada.
Almost 100hp from something so tiny is amazing. Imagine with boost, or better yet 2 rotars. The hp/liter is amazing
The good part is that in a plug-in hybrid, a rotary engine can be used under very controlled conditions and should last a long time. I was thinking there's a lot of room for optimizing internal combustion engines for use with plug-in hybrids (which, in my opinion, should be the prevailing tech for the next few decades) and we should see some radically different designs to optimize for that use.
Wankel engines, by design, do not last a long time.
You were obviously very happy about this! Yay for engineering!
If you are going to use the engine as a range extender only - why bother with different RPM:s? One of the pros with a range extender is that you just have to run it at one RPM and can optimize it for that RPM.
Nice, I totally had that vibration question that he answered at the end. I wonder if this will ever show up in a standalone generator, and how it would compare in power, size, and efficiency.
The wankel/rotary engine has good power to size, but it's really bad with fuel efficiency. The rotor simply cannot achieve high compression, when compared to a standard piston engine.
If you want a standalone generator, just get a Honda.
Great description of the technolgy man. I wonder what the efficencies compare like between the old wankel and this new set up and a comparable hybrid piston set up are.
I had a 1996 Jeep Grand Cherokee that controlled the current flow to the alternator rotor thus controlling the current output of the alternator and it's mechanical load on the 4.0l motor. Also there was a temperature sensor under the battery which the ECU monitored and when the battery was cold the rotor received more current and thus warmed the battery up and kept it charged to maximum. The O2 heater uses more energy until open loop running conditions as well so this must not be new tech they are using but just a new combination... yet.
I'm glad Mazda is bringing back the rotary!! Thanks for the explanation on how it works.
It's just another hoax like the RX9
I'm excited to get hands on the new rotary engine in general. I'm curious to see if the irons will work with the old 13Bs or not. The slightly larger displacement and direct injection is also a nice technological step forward. I think in the aftermarket world these new rotaries could be very interesting.
I was thinking the same !!!
The single rotor displacement being bigger than the single rotor of the Renesis is interesting. It's suggests that it might be the dimensions of the 16X prototype, and one the advantages of those dimensions was that it was a narrower but longer rotor. Back to the width of the 12B for greater efficiency, since they found that the 13B width wasn't actually burning fully to the corners, but also more eccentricity for more leverage on the e-shaft and more torque as a result. Based on the numbers of the single rotor, I would suspect a dual rotor would be a noticeable improvement over the Renesis.
My thoughts exactly! We know that Mazda actually loves all the advancements that the aftermarket scene has brought to the rotary engine. So, hopefully, they kept that sentiment while designing the new rotary. Only time will tell, but you know that once the gearheads can get their hands on the new rotaries things are gonna get crazy.
@Lurch but the irons have porting, coolant passages, and oil galleries. It's a bit more involved than just plates. And yes it could be possible to design from scratch but a large majority of us don't have access to a cnc for experimentation.
Just happy they are bring the tech back if it is good and reliable they may be inclined to build one for a sports car
This will be a great museum piece.
I'd love to have you as a college professor. You're super entertaining and into the subject!
this is interesting. the rotary can also be used to warm up the battery too in sub freeze temp. Example: in sub freeze let the rotary run first to warm up the coolant that connects to the battery while also warming up the cabin
It's a really good idea. I've been saying Mazda should use a small rotary as a generator for about 15 years.
And it takes literally 5 minutes to do so. Not the hilarity you see in other videos of waiting 2 or 3 hours to start charging when it's below freezing. It would also supplement the plug-in charging if done right in cold weather. Your Tesla? Still waiting 30 more minutes to start chargning and you're down the road.
If you warm up the coolant, isn't that fluid really a heatant?
@@tar170 both to heat when cold or to cool when hot. Just need a valve to shut off the path from engine to battery and path from battery to radiator to cool
Rotaries have primary and secondary inlet ports, except the 192 regenesis, I think. These act as variable valve timing, primary always open and secondary above a set rpm.
Was just about to say the same thing. There's a cylinder that rotates inside the port that can change the port size. I believe the renesis has six different intake settings that act as a sort of pseudo VVT.
Neat! Useing the generator in this way is kinda like removing or adding weight to obtain a desired effect on the acceleration of a vehicle instead of adding or removing power.
i love Mazda's persistence
I love to see the progression of the idea! The first design with the additional motor was complex, confusing, and likely very expensive. Second design, simpler uses existing components. All you have to do is pulse width modulate the generator, and magically, you can now control the actual load of the engine!
Seems complicated. Can't we just teleport by thought alone where we want?
Jokes aside, thank you for the breakdown of the inner workings, I love learning how stuff works. 🙂
What an amazing solution using the generator to control the timing. Hope it works great. I miss the Wankel engine in Mazda vehicles. I would work on changes on the valve variable sizes to control the intake with a crescent rotary valve, this way they won’t need to change the speed of the rotary witch goes against it’s nature of nice easy rotation.
normally i hate when people talk to much but on this channel i love it
Closing the intake valve sooner at lower RPM also increases dynamic compression which creates more torque. It also creates less pumping losses at a given load to increase fuel efficiency.
wouldnt this be a Miller cycle?
@@Akira-nw4jl No, the miller cycle is much more involved than that.
It may not be the rotary we wanted, but it’s rotary we need🙏😂
Edit: Curious to see what level of efficiency this design actually achieves
Seeing as how rotaries are literally known for being the most thermally inefficient engine design. Which means they need much more fuel for the same power output as piston engines....
Not good
@@rahpowah01 true but i think ge means in a relative fashion to the rx7’s
Brilliant solution!
Its really interesting how complex they made the intake system, instead of the old simple way using variable intake runners they added a multi layer motor and inverter system that really adds load to all the parts instead
If only we had classes like this in high school
The only things highschool teaches children are to cut off their genitals and to fight FOR communism to violently destroy america from within.
That would be very much so a waste of class time despite your personal interest in the topic.
@@dzello id rather waste my time learning about this than learning something i don't enjoy
@@natgobrrOW And that's why this video is here, not in high school. Because if you want to learn that, you can use your time here.
Not exactly how we wanted it, but glad to see they're still improving on the doritos. The dream lives on. I'd be interested to learn how they've played around with these improvements in a combustion only design.
I think it's crazy they are using aluminum housings, I would think the coefficient of thermal expansion for aluminum would make them a no go. But I guess if everything is aluminum then it works out in the long run, especially considering the ceramic coatings.
@@anydaynow01 the housings where already aluminum in rotaries. It was just the caps that close the combustion chambers that weren’t
Fantastic work 👏 👍 👌
That was Insane
Crazy these motors are still being used!
P.S. Glad to see my old engine is still being used in your videos. That engine is still running strong!
Time stamp?
this one here is the lowest revving rotary ive ever heard of...LOL
In the late 90's and early 2000's, Arctic Cat started equipping their 2 strokes with devices called "Arctic Power Valves" (APV). They would press right up against the piston, keeping a small "exhaust manifold" volume, but after about 6,725 RPM, a cable pulls the valve away from the cylinder, effectively increasing the volume of the exhaust manifold, allowing more exhaust gas to leave the cylinder more quickly. It was a solution to provide more torque at low RPM without inhibiting high RPM power. Why do I bring this up? I can't see why Mazda couldn't have done something similar by adding a valve along the wall of the "cylinder" to effectively increase the size of the intake port to allow more air in at higher RPM.
I had the same thoughts. Intake and exhaust ports could simply change diameter to control the gas flow more precisely than manipulating with rotation speed. Maybe it would be too complicated or less effective in practice due to a) the necessity of installing variable port diameter inside of side housing b) the length between insides of combustion chamber and valve located on the outside of a port.
reminds me of Yamaha Powervalve System YPVS
As always a great video. I teach stuff like this for a living and hire others to teach. I wish I could clone you and keep them in classrooms.
I don’t use Telegram
Thanks for the details I really enjoy your videos. I personally think the near term (next 15 years) solution for improved fuel economy and reduction in emissions is a plug-in hybrid capable of 60-ish miles with range extending small engine. This would allow smaller batteries at around 25 kWh and perhaps a 6 gallon gas tank. If the driver recharged frequently they would barely use any gasoline, for most driving, but should be able to drive 250-300 miles, re-charge quickly and fill up the tank. This would permit drivers to become familiar with electric recharging, and the supply of material that goes into cars would stretch 3-4 X, the weight of the car could be reduced by 500 pounds, fuel economy would g way up emissions way down.