The Military Wants Ceramic Submarine Hulls

[kernals12]

Chrysler was able

What Chrysler vehicle used a turbine? A vehicle that was older than most members on this board. In a half-century since, there hasn't been improvements that could cause such a thing to become viable. Chrysler stopped development because of emissions and poor fuel economy. So what would a turbine contribute today?

Well a ceramic material that's ductile not brittle makes that possible, or at least it would if not for the imminent dominance of the electric vehicle.

[kalvado]

What correlation is there between ceramic hulls and automotive turbine engine development?  It isn't as though the turbine didn't get the old college try by auto manufacturers. 

probably the idea that technologies, including advanced materials, tend to trickle down from most demanding applications to more mundane.
composites may be a good example, which is still making its way into the general car market

Fair enough, but composite materials don't necessarily solve the issues of packaging a powertrain (as noted in the above comment).  Even the early nuclear car concepts never really got off the drawing board because there was no way to solve the exhaust issues.

It's not about power train, it's an example of advanced material.
Composite bodies for race cars seem to be a thing. Lighter, stronger, hard to repair, more expensive (at least for now). Composite planes are a thing right now.

What correlation is there between ceramic hulls and automotive turbine engine development?  It isn't as though the turbine didn't get the old college try by auto manufacturers. 

It's actually very interesting. Kerosene burns at about 3500 degrees fahrenheit, gasoline slightly more. Such heat will easily melt all but the most exotic metals. That's not a problem for piston engines because combustion is intermittent and it's easy to provide external cooling. Turbine engines don't have the same luxury, as combustion is continuous and the turbine blades are always going to be exposed to the heat. Engineers can only fix that problem by running the engines with lots of excess air. That keeps the engine from being destroyed, but it also hurts fuel economy because you need a bigger compressor to get the same amount of output.

Beginning in the late 60s, engineers looked at ceramics for the solution. They can handle much higher temperatures than metals (and they're also cheaper and lighter). If they could just get over ceramics' brittleness, they could make turbine engine more efficient than a diesel. But that never happened.

Still have to exhaust that heat somewhere.  That was a major issue with the turbine car concepts, stepping behind the exhaust could lead to a bad time. 

Heat in exhaust is lost energy. Noise, high fuel burn..
As far as I understand, small turbines are difficult due to more strict tip seal requirements. And that is a fast seal, unlike slower piston ring.
I believe there are turbine tanks, but not even heavy military support vehicles....

[02 Park Ave]

Parnelli Jones drove a turbine powered car for Andy Granatell (STP) in the 1967 Indy 500.

He led most of the race but failed to finish when he experienced a transmission failure eight miles from the checkered flag.

[kernals12]

I'm looking forward to ceramic cars and houses.

[kalvado]

I'm looking forward to ceramic cars and houses.

Bricks are a flavor of ceramic. Jus'saying.

[kernals12]

I'm looking forward to ceramic cars and houses.

Bricks are a flavor of ceramic. Jus'saying.

Hence what I said about DARPA sending us back to the stone age

[Scott5114]

Artificial diamonds are already mass produced. It takes 2 weeks under extremely high pressure under current processes, which is expensive. And even if that wasn't an issue, diamonds are very difficult to work with and they are quite fragile. Not very desirable for making a submarine hull.

They could always try using spades or clubs instead. (Not hearts, they're easily broken.)

[kernals12]

The great thing about ceramics is they are made from unbelievably abundant substances. 28% of the earth's crust is silicon (silicon nitride and silicon carbide). In the future, our cities may be made of the very dirt that was excavated to build them.

[kalvado]

The great thing about ceramics is they are made from unbelievably abundant substances. 28% of the earth's crust is silicon (silicon nitride and silicon carbide). In the future, our cities may be made of the very dirt that was excavated to build them.

Lol... Wait until you see rare earth ceramics.