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Old June 30th 20, 05:40 PM posted to rec.aviation.piloting
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Default ZeroAvia's Val Miftakhov makes a compelling case for hydrogen aviation

Larry Dighera wrote:
On Tue, 30 Jun 2020 00:00:07 -0000, wrote:

Larry Dighera wrote:
On Tue, 23 Jun 2020 23:36:54 -0000,
wrote:


snip

Don't forget the energy required to do something with the
hydrogen to make it usefull, such as compression.


Liquid H2 doesn't require compression, only cooling; LH2 is stored at
ambient atmospheric pressure.


What part of "such as" did you not understand?

You do in fact have to compress hydrogen to get LH2 in significant
quantities.

Did you think you just put it in a -430 F refrigerator?

https://en.wikipedia.org/wiki/Liquid_hydrogen

Try doing a google search for liquid hydrogen production to see
what it actually takes to produce LH2 in significant quantities.

You are correct to mention the power required to produce LH2. It is
surprising how little power is required by a cryo-cooler. The
cryo-cooler in this video https://www.youtube.com/watch?v=7PWESWqhD8s
only required ~150 Watts for ~one hour to produce ~four oz of liquid
air.


Whoop de ****ing do, yet another tiny garage lash up of surplus
equipment.

The energy required to cool a mass by 500 F is a themodynamics problem.

To know the true energy requirement, you also need to know the
energy efficiency of your cooling device.

And again, if airports won't offer MOGAS, what in the world makes
you think there is any motivation to install a hydrogen production
facility?


You are thinking in the immediate present; I'm thinking in the future.


I am thinking about known physics and engineering.

While you are fantasizing, be sure to include dilithium crystal
warp drive.

snip irrelevant BLM comment

--
Jim Pennino