Fwd: Please pass to Baiju Bhatt

[Keith Henson]

No reply for a week.

Not surprising, the standard in recent years seems to be to ignore
email contacts.

Keith


---------- Forwarded message ---------
From: Keith Henson <hkeith...@gmail.com>
Date: Wed, Dec 11, 2024 at 6:26 PM
Subject: Please pass to Baiju Bhatt
To: <con...@aetherflux.com>


Hi Baiju

You may know me by reputation,

https://en.wikipedia.org/wiki/L5_Society

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

I worked for years on power satellites and moderate the Google Group
Power Satellite Economics. That group has most of the people who are
active on the subject. You are welcome to use it for recruiting or
research.

The Aetherflux website mentioned that you are or were looking for a
thermal engineer. I am retired and not looking for a job, but am
willing to remotely consult, paid or unpaid.

Large power satellites have huge heat rejection needs. A solution was
to use tapered plastic tubes full of low-pressure,
low-temperature condensing steam. In multi-GW sizes, this got the
mass down to around a kg/kW.

There are some tricks in radiator design that date back to the paper
Eric Drexler and I wrote in 1979. You should put the heat sources on
both ends of the radiator tubes and operate them in pairs.

When I was working on the design spreadsheets I was surprised to find
that the system mass went down with a lower temperature. The reason is
that the vapor pressure of water (and the heavy wall thickness) goes
down faster than T exp 4th goes up over the range for liquid water.

If you want a visual of what such a radiator would look like,
https://www.youtube.com/watch?v=VEkZkINrJaAr Beamed Energy
Bootstrapping. About 5 minutes into the video there are construction
details for a 1.5 GW radiator, 60 tubes at 25 MW per tube.

The lightweight reflectors between the tubes keep them from "viewing"
each other and send all the radiation into space. The radiator is
edge-on to the sun and has a (not shown) sunshade around it to keep
sunlight off the radiator.

Each tube terminates in a centrifugal slinger that sorts out the
liquid water and sends leftover steam plue new steam into the paired
radiator tube.

I have also considered lasers, for powering a Skylon-type vehicle to
orbit. https://htyp.org/design_to_cost#Space_laser

If you want me to talk to your technical people, I can do so on Zoom,
Skype, or phone, 626 264 7560,

Best wishes,

Keith