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Joined 2 years ago
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Cake day: July 24th, 2023

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  • Trusting the float on the back makes sense to be a hard one. It’s counterintuitive, the water comes over your face when you start, and you can’t hold on to anything. Might be worth getting a personal coach for a session just for that if you haven’t already. Someone supporting you might help with the anxiety as long as they’re encouraging and not pushy.


  • The problem isn’t a missing technology. it’s our political and economic system.

    I’m all for advancing tech but nothing is going to work until we fix our behavior. We use fossil fuels because they’re profitable and allow or growth-at-all-cost economy. There’s nothing for which they’re the only option. Only a few things for which they’re the best option; the power grid and transit aren’t on that list.


  • No. The heat of combustion increases the gas temperature. But this temperature increase is relative to the mass of the gas. The heat is relative to fuel/oxygen mass combusted. (Combustion energy + Ideal gas law)

    Add mass without adding combustion, you get lower pressure and temperature out. So you get less boost from the turbo and make more work for the compression cycle.

    The major point of the turbo is to use wasted heat to add more oxygen by packing more air in. So it’s a bit of an odd question to answer. The point is there’s a lot of energy wasted in a naturally aspirated engine’s exhaust. Turbos mostly use that wasted energy, and not power from the crank.

    Oh yeah, the turbo is going to have an efficiency ratio for converting exhaust pressure into boost. So that added backpressure on the exhaust is going to be offset in the intake stroke by that ratio. Not important to the point, hat a tidbit. These things are so complicated lol.



  • The exhaust gases are at a high pressure after combustion due to combustion heat. The turbo does indeed increase exhaust pressure, and therefore extracts some work from the crank but it’s extracting significantly more from the high pressure of the expanded hot gas. It’s not “free” because it’s energy that is usually just wasted in a naturally aspirated engine. There are many examples of engine configurations where a turbo is used to boost efficiency by reducing displacement.

    There were systems on old aircraft engines which used exhaust power recovery turbines geared directly to the crank. Those wouldn’t physically function under your concept.

    The increase in manifold pressure doesn’t just increase oxygen in the cylinder. It also increases the manifold pressure, or the total mass of gases. The increase of oxygen does allow for more fuel and total energy in the ignition event but the extra inert gas also expands when heated. So both play a factor in increasing mean effective pressure, and therefore energy output per cycle (power).

    Edit: im tired… Bad wording, adding inert gas to increase intake mass doesn’t help.








  • Ehhh… Well, in computer processing it does play a huge role in heat transfer requirements which has often driven transistor density.

    But fair to say efficiency is often more likely to create induced demand rather than a net reduction in consumption

    Higher fuel economy -> more cars interplanetary frigates

    Cheaper logistics -> more goods transported between systems

    Faster internet -> more galactic utilization

    More railways -> lower profit for the car speeder industry, uhh… Wait! I meant more transit by rail demand?

    Edit: forgot which sub…