Future Planetary Exploration |
Future Planetary Exploration |
Oct 20 2008, 07:11 PM
Post
#1
|
|
Member Group: Members Posts: 715 Joined: 22-April 05 Member No.: 351 |
I've started a new blog on this topic at http://futureplanets.blogspot.com/
This blog supplements UMSF by allowing on topic discussions that include politics and other topics not appropriate here. The first entry is up with some additional news on the MSL funding and schedule problems. -------------------- |
|
|
Dec 8 2010, 08:09 PM
Post
#2
|
|
Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
Here's a crazy idea for a power source. How about running a Stirling engine between the Venus atmosphere and a block of frozen water? As the water warms, melts, and evaporates, it could provide a heat sink. As the steam heats up, the engine would be less efficient, but the steam itself could power a piston or rotate the generator once its pressure is significantly higher than the exterior; steam at Venus temps should easily be 200+ bars (if allowed past planetary protection).
Basic b-o-t-e calculations (per kg of H2O) Starting at -200 C to 0 C, ~1.5 kJ/kg = 300 kJ Latent heat of melting = 334 kJ 0 to 100 C, ~4.2 kJ/kg = 420 kJ Latent heat of vaporization = 2260 kJ 100C to 460C, ~6.4 kJ/kg = 2350 Total heat required to raise from -200C to +460C = 5.66 MJ. A kg of gasoline, as a comparison, has about 44 MJ/kg. Now granted, you probably wouldn't get very high efficiency, and the whole time your cold area is going to get heat leaking in, but it is an interesting thought exercise. -------------------- Space Enthusiast Richard Hendricks
-- "The engineers, as usual, made a tremendous fuss. Again as usual, they did the job in half the time they had dismissed as being absolutely impossible." --Rescue Party, Arthur C Clarke Mother Nature is the final inspector of all quality. |
|
|
Lo-Fi Version | Time is now: 27th September 2024 - 02:59 AM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |