Re:Airbus pioneers a superconducting powertrain cooled by li...
by XorNot on Wednesday April 21, 2021 @10:22AM
(#26890059)
You still have to cool a combustion engine - hence why car's have radiators.
Combustion engine's are also limited by Carnot cycle engine efficiency - about 64% theoretically, no more then 50% in the real world. So you're still going to wind up having to dump progressively more heat from a fixed surface area.
Re:Airbus pioneers a superconducting powertrain cooled by li...
by ethbr0 on Wednesday April 21, 2021 @10:55AM
(#26890470)
(Post coffee) Cars have radiators to cool the operating structure (e.g. engine block), but that cooling's ancillary to power produced, no?
Carnot cycle was what I was grasping for.
Original point being that in a thermal engine, increasing your temperature gradient by increasing your high-temperature side (while holding exhaust constant) leads to more potential power.
Or IOW, a thermal engine that doesn't burn hot somewhere isn't going to produce much power.
(Electric being a completely different ball of wax)
In electric, heat is the enemy and inefficient.
In combustion, heat is a key component of the thermodynamic efficiency, unavoidable, and effectively only limited by material tolerances.
(I didn't major in physics, so someone keep me honest on the ceiling / floor efficiency equations for combustion engines?)