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“Inside-out Wankel” rotary engine delivers 5X the power of a diesel

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Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#151

Post by rgmerk »

astral303 wrote: post #74
mywittyname wrote: post #10

A non-turbo diesel is an interesting choice of competitor. The big selling point of the Kohler motor is that it's almost silent - even the valve train is belt-driven to reduce noise. Not sure a rotary engine screaming at 6500RPM is comparable here to a diesel with a peak torque at 2000 and peak power at 3600. > LiquidPiston has been working on these X-engines for nearly 20 years now, I'm guessing they will never actu…

rotary engines do not really scream at peak power... this is why Mazda has plans to use rotary at peak power to generate electricity for their hybrid EVs. re 20 years to make a new engine point, compare investment $ in traditional ICE across the car industry vs investment $ into rotary or other alternative engines (the former is order of magnitudes more)

As cool as the rotary engine is, Mazda’s attempt at a rotary hybrid is flogging the deadest of dead horses.

Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#152

Post by m463 »

mywittyname wrote: post #10

A non-turbo diesel is an interesting choice of competitor. The big selling point of the Kohler motor is that it's almost silent - even the valve train is belt-driven to reduce noise. Not sure a rotary engine screaming at 6500RPM is comparable here to a diesel with a peak torque at 2000 and peak power at 3600. > LiquidPiston has been working on these X-engines for nearly 20 years now, I'm guessing they will never actu…

btw: I had a mazda rotary engine car, and the 7000rpm shown on the tach seemed exciting compared to a piston engine... except it wasn't really true. It really ran at 1/3 that speed.

Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#153

Post by digdugdirk »

bmelton wrote: post #54
digdugdirk wrote: post #44

Earlier quoted context omitted.

Mazda really seems like the only company innovating in the ICE space (this, wankel rotary engines, skyactive engines) and their cars look damn good these days too. On top of that, they make fun cars. With buttons and knobs on the dash! I'm glad they're still around doing their thing.

Agreed, but there's also Koenigsegg, which has managed to eliminate the need for cams, and complete heads from ICEs, replacing them with their 'freevalve' tech (which basically replaces the timing chain with computers so that instead of having one or two modes that a camshaft can opt into, you can precisely dial in bespoke timings for every RPM, or every RPM and speed, or ever RPM / speed / gear combination. They've…

Absolutely love Koenigsegg, and their new engines are probably the current state of the art in (small scale) production ICE engines.

I just feel like Mazda doesn’t get enough credit for the innovation they manage to accomplish at a truly mass produced scale. It's almost like they're too "normal" to get the attention they deserve.

Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#154

Post by m463 »

93po wrote: post #30
shadycuz wrote: post #21

Earlier quoted context omitted.

The engine is the size of a push mower. > XTS-210 is about the size of a basketball, weighs in at 19 kg (42 lb), and displaces 210 cc. So you are talking about a 26HP lawn mower. While the Camry might make more power at its normal size. It would not if you scaled it down to the size of a basketball. I'm guessing it would make 1-3HP at that size.

A Traxxas 5407 TRX 3.3 engine used in RC cars makes 1.42 horsepower, weighs 305 grams, and fits in the palm of your hand. This is 1hp per 0.46 pounds of engine weight, nearly three times better than the camry engine. Granted an RC engine runs on a mixture of fuel and nitromethane, and doesn't have any reasonable durability compare to a Camry engine. But it also only costs $200.

I'm not familiar with that engine, but I remember having little glow-plug engines and they didn't even have piston rings. (and were not efficient)

Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#155

Post by heelix »

rgmerk wrote: post #151
astral303 wrote: post #74

Earlier quoted context omitted.

rotary engines do not really scream at peak power... this is why Mazda has plans to use rotary at peak power to generate electricity for their hybrid EVs. re 20 years to make a new engine point, compare investment $ in traditional ICE across the car industry vs investment $ into rotary or other alternative engines (the former is order of magnitudes more)

As cool as the rotary engine is, Mazda’s attempt at a rotary hybrid is flogging the deadest of dead horses.

We will be driving an old RX7 in the '24 hours of Lemons' this year. Looking forward to pushing it in a nice casual race. Mechanically, we were not at a point where it was solid enough for 2022. I think the rotary engine was the only thing that was working. :)

Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#156

Post by DesiLurker »

tda wrote: post #112
DesiLurker wrote: post #107

I know this is targeted towards military/aviation applications (now, initially it was different), but, I honestly cannot understand why there is so little research on just making a hyper-efficient low-maintenance engine that runs at maybe 2 optimal rpms and powers a small battery bank plus electric motor (i.e.. typically series hybrid). None of these gas engines will come anywhere near the power-per-pound & torque ou…

Are you aware you are essentially describing the original Toyota Prius? the engine is optimised for constant low rpm/low torque/high efficiency, whilest relying on the battery/electric motor for torque and temporary extra power

yes I am well aware of Prius series configuration but it is still a regular engine shrunk down and fine tuned. What I am asking for is something very ground up redesigned for maximizing one thing only efficiency of energy conversion. couple of examples of this are Aquarius engines or [1]. basically you cut out all the unnecessary stuff and all the maintenance/repair plus cost with it. Current engines are complex because they are operating over a large range or rpms and optimizing for other factors like torque etc. the you have losses in mechanical power transfer at each stage. Cut that all out and make something thats super easy to manufacture & replace and you have added another 50 years to ICE.

1: https://www.youtube.com/watch?v=u4b0_6byuFU

Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#157

Post by aidenn0 »

pas wrote: post #73
aidenn0 wrote: post #64

Earlier quoted context omitted.

And precisely 1/18 the MTBF

but it fails gracefully, right? (only one engine fails at a time) it's like RAID, great until the RAID card itself fails

It's probably most like losing power in a single cylinder; the effects vary from engine to engine.

Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#158

Post by jacquesm »

heelix wrote: post #155
rgmerk wrote: post #151

Earlier quoted context omitted.

As cool as the rotary engine is, Mazda’s attempt at a rotary hybrid is flogging the deadest of dead horses.

We will be driving an old RX7 in the '24 hours of Lemons' this year. Looking forward to pushing it in a nice casual race. Mechanically, we were not at a point where it was solid enough for 2022. I think the rotary engine was the only thing that was working. :)

Good luck with the seals! Between rotary and Stirling I find it hard to pick a favorite and both of them have similar problems despite the completely different geometry.

Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel

#160

Post by jacquesm »

aidenn0 wrote: post #157
pas wrote: post #73

Earlier quoted context omitted.

but it fails gracefully, right? (only one engine fails at a time) it's like RAID, great until the RAID card itself fails

It's probably most like losing power in a single cylinder; the effects vary from engine to engine.

They tend to seize and when they do and you gang them they'll likely break stuff in the other ones unless you add a freewheel or some other luxury like that.
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