Re: 39 days to Mars possible now with nuclear-powered VASIMR.

From	Thomas Koenig <tkoenig@netcologne.de>
Newsgroups	sci.space.policy, sci.astro, sci.physics, rec.arts.sf.science
Subject	Re: 39 days to Mars possible now with nuclear-powered VASIMR.
Date	2015-10-05 20:57 +0000
Organization	news.netcologne.de
Message-ID	<muuo8n$u15$1@newsreader4.netcologne.de> (permalink)
References	<mrpll4$bbk$2@dont-email.me> <MPG.304ab8e91e2164ea989898@news.eternal-september.org> <msqomf$t2m$2@dont-email.me> <mut0vc$sa2$2@dont-email.me>

Cross-posted to 4 groups.

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Robert Clark <rgregoryclark@gmSPAMBLOACKail.com> schrieb:

> Key for this is to get high efficiency conversion to electricity. What
> radiators do is dispense to space the heat that is not so converted. So if
> you had a system that only converted 5% of the thermal to electric energy,
> you would have to throw away 95% of the generated power. For large amounts
> of generated power the radiators needed would be large and heavy.

It is actually the opposite.

If your overall cycle gets rid of waste heat at high temperatures, you
can have small radiator areas - radiation power per area is proportional
to the fourth power of the absolute temperature of your cooling system,
and maximum efficiency of a reversible thermodynamic cycle (equivalent to
the Carnot cycle) is 1 - t_cool / t_heat.


> As a model for how the conversion would work look to the SSME hydrogen
> turbopumps. They were quite lightweight at 150 kw power per kg at high
> efficiency, ca. 80%.

Please learn about the difference between the efficiency of
a thermodynamic cycle and the efficiency of a single part of
a process.

Thread

39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-08-28 08:56 -0400
  Re: 39 days to Mars possible now with nuclear-powered VASIMR. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2015-08-28 19:29 -0400
    Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-09-09 22:10 -0400
      Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-10-05 01:16 -0400
        Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Greg \(Strider\) Moore" <mooregr@deletethisgreenms.com> - 2015-10-05 07:07 -0400
        Re: 39 days to Mars possible now with nuclear-powered VASIMR. Thomas Koenig <tkoenig@netcologne.de> - 2015-10-05 20:57 +0000
          Re: 39 days to Mars possible now with nuclear-powered VASIMR. gilber34 <fafa@invalid.com> - 2015-10-07 00:06 -0500
            Re: 39 days to Mars possible now with nuclear-powered VASIMR. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2015-10-07 06:07 -0400
              Re: 39 days to Mars possible now with nuclear-powered VASIMR. Rick Jones <rick.jones2@hp.com> - 2015-10-07 17:07 +0000
              Re: 39 days to Mars possible now with nuclear-powered VASIMR. gilber34 <fafa@invalid.com> - 2015-10-13 12:06 -0500
          Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-10-08 20:16 -0400
            Re: 39 days to Mars possible now with nuclear-powered VASIMR. Thomas Koenig <tkoenig@netcologne.de> - 2015-10-14 15:19 +0000
              Re: 39 days to Mars possible now with nuclear-powered VASIMR. Fred J. McCall <fjmccall@gmail.com> - 2015-10-14 08:30 -0700
                Re: 39 days to Mars possible now with nuclear-powered VASIMR. Thomas Koenig <tkoenig@netcologne.de> - 2015-10-14 16:57 +0000
                Re: 39 days to Mars possible now with nuclear-powered VASIMR. Fred J. McCall <fjmccall@gmail.com> - 2015-10-14 22:11 -0700
              Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-10-16 16:46 -0400
                Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-10-30 01:51 -0400
                Re: 39 days to Mars possible now with nuclear-powered VASIMR. Thomas Koenig <tkoenig@netcologne.de> - 2015-10-31 12:32 +0000
                Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-11-08 09:12 -0500
                Re: 39 days to Mars possible now with nuclear-powered VASIMR. Thomas Koenig <tkoenig@netcologne.de> - 2015-11-08 14:36 +0000
                Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-11-12 13:19 -0500
      Re: 39 days to Mars possible now with nuclear-powered VASIMR. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2015-10-13 08:19 -0400

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