Watch: See inside a (tiny) running rotary engine

Warped Perspective shows the inside of a running single-rotary Wankel engine

Watch: See inside a running rotary engine | Autoweek

 

As the title says. Enjoy

 

Whoops, I tried searching before posting, but I didn't find this thread.
Sorry for the duplicate...

 

Says this is a 2018 video. Linked just for fun here.Enjoy

 

there's a fair amount of liquid fuel in the chambers on some of those test runs!

 

The fuel is nitro, it's supposed to run rich, but that's excessive. In the comments he says he couldn't get it to run any leaner :/
Fundamentally it illustrates the rotary problem: long combustion chamber where optimal conditions for combustion exist only in the middle-ish. The rear of the face isn't doing a damn thing.

 

Yes but the two spark plugs, leading and trailing of our Mazda rotary engines,do help to spread that combustion over more of the rotor face than with this single glow plug in this model airplane engine.

 

Hmm, I wonder why not 3 spark plugs? Cost?

I mean, the 787B 26B engine had 3 spark plugs for each rotor and it looks like the new shoebox range extender also has 3 ignition wires attached to one side of the engine.

 

love it..thanks for posting.

Now RE noobs 'may' get a better understanding on how, particularly engine flooding, emissions, fuel economy, etc.
And why Mazda has huge engineering problems even getting close to regulatory targets for today's 'green' world.
And I am not going to spell it out if you cant see it.

Hydrogen was and is the future for a RE powered only car, but we know why it will probably never happen.

R I P

 

I have one of those engines powering a little Q500 type RC airtplane.
These engines need a minimum of 25% oil in the fuel, most of it being castor oil. So that fluid sloshing around could very well be oil.
As a matter of fact, when I quickly advance the throttle I can see a spray of white liquid coming out of the exhaust before the "normal" exhaust smoke is restored: that's a stream of hot oil being ejected...

 

10,000 rpm = meh ....

(Recommend skipping to 4:00 mark and viewing from there)

 

Well, 29000 rpm while not doing anything useful, like spinning a propeller to cool itself

I wonder how many seconds it would last if held at that speed, especially with no cooling other than the fuel itself...

 

It's just air-cooled rather than liquid-cooled. Forced convection would help, but probably not necessary.

The thing doesn't have much of a load on it, and I doubt it generates enough heat as it generates like 0.01 HP of mechanical power. The dude even put his finger on the engine and he doesn't get burnt.

 

Not to mention RC engines are terribly inefficient due to their small size; even the piston RC motors consume high amounts of fuel due to: poor fuel metering/injection control and small piston cross-sectional area. I would say any issues that afflict normal-sized engines are merely exaggerated in RC motors, in addition to the lubrication factors and use of nitro-meth mixtures.

 

I disagree. I have one of those engines and it is known to be a hot-running engine even when it is fitted with a propeller and installed in an airplane, where it gets plenty of cooling air. There is a recommendation not to run it on the ground for extended periods to avoid risking overheating issues.

Also, even if there is no "explicit" load on that engine, that means that it's using all of the power it produces at 29000 rpm into overcoming its internal friction and pumping losses. I have no idea how much power it may make at that RPM, but for sure it's more than 0.01hp. Bear in mind that, according to the manufacturer, it produces 1.27hp at 17000 rpm. Even if it the power curve drops significantly between 17000 and 29000 rpm, I doubt it can be producing less than 0.5hp at 29000 rpm. And that means 0.5hp worth of heat with zero cooling airflow. Not good...

True, the surface to volume ratio gets worse with smaller engines, just to say one thing.
That said, fuel efficiency is not as important for RC engines as it is for full size engines (at least up to a certain point). Reliability and power to weight ratio are more important. That's why some folks run alcohol fuel even with spark-ignition engines, where they could use much cheaper gasoline instead.