TURBOS ON TURBOS ON TURBOS ON TURBOS.

"Cryptopygia - Front Wheel Drive is Best Wheel Drive" (cryptopygia) 01/13/2016 at 23:45 • Filed to: None

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And some doritos, for good measure...

BoxerFanatic, troublesome iconoclast. > Cryptopygia - Front Wheel Drive is Best Wheel Drive 01/13/2016 at 23:57

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Whiskey Tango Hotel???

Why not just use this?

Just cut out the middleman.

Axial > BoxerFanatic, troublesome iconoclast. 01/14/2016 at 00:00

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Three words:

High heat exhaust.

BoxerFanatic, troublesome iconoclast. > Axial 01/14/2016 at 00:03

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Yeah, because three scratch that, FOUR close coupled turbochargers on likely a peripheral port 20B rotary aren’t hot...

Zipppy, Mazdurp builder, Probeski owner and former ricerboy > Cryptopygia - Front Wheel Drive is Best Wheel Drive 01/14/2016 at 00:04

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Brapbrapbrapbapbapbrapbabababab. such an awesome idle.

Axial > BoxerFanatic, troublesome iconoclast. 01/14/2016 at 00:37

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The exit exhaust gases are not dangerously hot all the time, though. With a gas turbine, they are. Chrysler had trouble with it on their turbine car in the ‘60s. More recently, Jaguar had problems with it on the CX-75, which was one of the reasons they went for a high-strung four-pot on the cancelled production version instead.

It continues to be one of the biggest reasons why turbines still aren’t suited for automotive use, even when they’d otherwise be a great choice for an always-on hybrid-electric drive train.

Baeromez > Cryptopygia - Front Wheel Drive is Best Wheel Drive 01/14/2016 at 00:48

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samssun > BoxerFanatic, troublesome iconoclast. 01/14/2016 at 00:58

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Video says 4 turbo 4 rotor

Jewish Stig > Cryptopygia - Front Wheel Drive is Best Wheel Drive 01/14/2016 at 03:15

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Bro... do you even boost?

RangerSmith > Cryptopygia - Front Wheel Drive is Best Wheel Drive 01/14/2016 at 05:11

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Love me some RX-2!

BoxerFanatic, troublesome iconoclast. > samssun 01/14/2016 at 15:18

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Amazing, but still...

Turboshaft. So many fewer moving or critical stationary parts, and so much less plumbing.

Yes, that is a pencil next to that micro-turbine.

Yes, the exhaust is hot, but it is likely easier to incorporate multiple turbine stages to harness as much of the thermal energy as possible, and then diffuse the remaining exhaust with cool ambient air, possibly even with a turbofan-like bypass compressor into a positive pressure blown diffuser. It isn’t 1963 anymore, and technology has come a long way since the Chrysler Turbine car.

BMW experimented with a steam-medium thermal energy recovery system for a little while... using the exhaust of a piston engine to generate steam, and then harnessing the energy that way. theoretically there is technology that could be used to harness the excess heat output of a rotary or turbine engine.

Four rotors driving four turbos through intercoolers, with oil coolers, and water coolers, and coolers on top of coolers... is a lot of chances to fail. RX7s with sequential dual turbos were problematic enough to keep running reliably...

I have wanted to see a twin-charged rotary instead... a Rotrex variable-drive supercharger as a first stage, and a BIG high-volume turbocharger, rather than a sequential turbocharger. Turbos waste some thermal energy through the waste gate, in order to keep the compressor stage and engine happy. Superchargers are directly suited to the fluid dynamics of the engine, at least ideally, and especially at lower RPMs.

Otherwise, a blow-down turbine compounding unit. (turbine that runs on volume of flow, rather than thermally-induced pressure differential, that turns a gear set that adds kinetic energy to the rotary’s output through the eccentric shaft. somewhat like the turbine output stage of a turboshaft engine, but with an internal combustion engine as the heat source, rather than direct constant exposure to the combustion chamber)

But even that is more involved with more separate components than a turboshaft engine.

samssun > BoxerFanatic, troublesome iconoclast. 01/15/2016 at 05:34

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The two problems with turbines are that they get more efficient as you scale up, and they’re most efficient over a narrow speed range. So you either size for the average power you need, and it’s gutless, or you size for peak power, and it’s inefficient most of the time.

To me that says the only place a turbine would work is in a hybrid system where it could be sized for average output, running at a constant speed to charge your batteries which could dump a much higher amount of power through the motors when needed. But then you’re stuffing a turbine, motors, and heavy batteries in the same car...

It’s really hard to beat the reciprocating piston engine at the combination of efficiency, peak power, throttle response, and flexibility over a wide speed range. I think Leno’s car had something like 130hp / 425lbs-ft, between 20k & 40k rpm (imagine a redline only double your idle speed).

BoxerFanatic, troublesome iconoclast. > samssun 01/15/2016 at 12:22

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C-X75 actually was intended to be a hybrid drive, where the turbines were steady-state to run a generator power plant, the wheels were driven by traction motors.

I am not sure, but I have a feeling that power was scaled up or down by using one of the two turbines in lower-demand usage, and both for high demand, rather than throttling RPMs too much.

The only other thing I would say, would be some sort of clutch engagement that would kinetically engage the turboshaft output to the drivetrain at sustained high speeds, where electrical system heat and current draw start to degrade electrical efficiency. At sustained high speeds, direct kinetic drive is more efficient than two energy format transitions, kinetic->electric->kinetic.

Piston engines have more than a century of development, but still have a primary problem... reciprocation. wasting inertial energy at TDC and BDC on every stroke, for every piston and con-rod.

Rotary has it’s issues, but technical development can address them, especially in a series-parallel hybrid system, where the rotary isn’t lugging at low RPMS and high torque loading. It has some oscillation, but not the stop&reverse direction of a reciprocating engine, and FAR fewer moving parts.

But if there are going to be four turbines and four compressors, and a complete and utter nightmare of complexity and failure points surrounding that, there may as well be four compressor stages, and four turbine stages in a tube with a combustor between them, rather than a lot of plumbing to put an entire internal combustion engine between the compressor and turbine stages.

samssun > BoxerFanatic, troublesome iconoclast. 01/15/2016 at 18:25

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Lots of youtube turbo-turbines:

TheLOUDMUSIC- Put it in H! > Cryptopygia - Front Wheel Drive is Best Wheel Drive 01/17/2016 at 23:57

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bro do you even turbo?

Yes, there are 8. No, I don’t know why. All I know is that it is.