Sounds like it could be awesome for some GA applications given the lack of weight budget and it seems like they did solve the issues with rotaries. Hopefully someone starts cramming them in some experimentals!
“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
#12My understanding is that everyone acknowledges that rotary engines are great, bt in comparison to piston based engines they have far shorter longevity.
I understand this too, however, the technology might be worth revisiting with modern techniques, I understand the power output is 'smoother', which can reduce vibration, some applications might need that?
Nearly all engines need some level of vibration reduction if anything just to prevent it from damaging itself.
Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel
#13My understanding is that everyone acknowledges that rotary engines are great, bt in comparison to piston based engines they have far shorter longevity.
They're not great, at all. They have very few moving parts and they are very smooth because there are no reciprocating parts. Other than that, they have emissions like 2-stroke engines because of the incomplete combustion and we have never been able to devise any kind of material to make the apex and side seals last anything like as long as piston rings. Piston engines are a terrible way to power vehicles, but everyt…
Wankel engines are great in one respect, power density. But they have terrible reliability and fuel efficiency.
Turbine engines also have great power density and terrible fuel efficiency, but they are very reliable.
Diesel engines are reliable and fuel efficient but heavy.
This one appears to have improved reliability and fuel efficiency over the Wankel without sacrificing power density.
Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel
#14Ok, so they're "shooting for" a performance of 1hp per 1.57 lbs of engine weight. A Toyota Camry engine produces 1hp for every 1.41 lbs of engine weight. It produces 1ft-lb of torque for every 1.94 pounds of engine weight, compared to 1.58 for the Camry.
How is this revolutionary motor being outdone by a mid-range sedan engine?
Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel
#15I guess the "inside out" is that the rotary block is also the fuel injector? Would have to read more to figure out how they get fuel into a thing moving at thousands of rpm.
Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel
#16Ok, so they're "shooting for" a performance of 1hp per 1.57 lbs of engine weight. A Toyota Camry engine produces 1hp for every 1.41 lbs of engine weight. It produces 1ft-lb of torque for every 1.94 pounds of engine weight, compared to 1.58 for the Camry. How is this revolutionary motor being outdone by a mid-range sedan engine?
Add 10,000 or 20,000 lbs to the vehicle weight, does it all scale the same?
Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel
#17My understanding is that everyone acknowledges that rotary engines are great, bt in comparison to piston based engines they have far shorter longevity.
My near-mint condition 2009 Mazda RX-8 never had a Wankel engine problem (over 100k miles). It would have easily lasted another 5 years without a doubt or hiccup. Wankels are usually excluded from all engine comparisons, because it's a considered a different class...for piston engine marketing reasons. I sold off my RX8 in 2018 because my fiancee and I moved to Seattle (passing emissions testing wasn't anything speci…
More antic-data: i worked with a guy whose brand new RX-8 needed two engines in the time we worked together. Granted, his was a 04 automatic, which is the worst combo. But still, Mazda didn't go out of their way to extend the engine warranties on the early RX-8s for no reason.
Did you happen to have an 08+ model with the updated engine and/or remove teh catalytic converter?
Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel
#18Ok, so they're "shooting for" a performance of 1hp per 1.57 lbs of engine weight. A Toyota Camry engine produces 1hp for every 1.41 lbs of engine weight. It produces 1ft-lb of torque for every 1.94 pounds of engine weight, compared to 1.58 for the Camry. How is this revolutionary motor being outdone by a mid-range sedan engine?
Add 10,000 or 20,000 lbs to the vehicle weight, does it all scale the same?
I'm not sure what your point is. The XTS-210 hasn't been put in a vehicle as far as I know.
Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel
#19I guess the "inside out" is that the rotary block is also the fuel injector? Would have to read more to figure out how they get fuel into a thing moving at thousands of rpm.
We do this all the time with cylinders, no? I don't see how this is any different.
Re: “Inside-out Wankel” rotary engine delivers 5X the power of a diesel
#20My understanding is that everyone acknowledges that rotary engines are great, bt in comparison to piston based engines they have far shorter longevity.
My '88 RX-7's engine went 120k miles before I decided to rebuild it and it still probably had a good 30k miles before it would have 'gone'.
This is completely normal through the 70s and 80s when these engines were popular. We didn't start getting million-miler cars until the Lexus LS400 came out.
The problem with the rotary is heat and the damage it does to other components. The RX-8's engine design was actually bad and doesn't adequately lubricate, but that gets 'fixed' in the last three model years.
The biggest reason that RX-7 owners have seal failures are often due to adding on too much power without adequately upgrading the fuel system. Keep in mind that Wankel engines are absurdly popular in the world of amateur aviation without any of the stigma.