In reply to thomas malloy's message of Thu, 3 Nov 2005 01:55:10 -0600: Hi, [snip] >Bruce posted; > >Podkletnov's device could be made into a >reactionless drive if we can get reliable mass production of his disks >and steady high voltage power supply. [snip] This is an ideal application for an isotope power supply. Because they produce particles at high energies, it is essentially only necessary to catch those particles, and a voltage equal to the energy of the particles (in eV) develops automatically. E.g. a 5 MeV beta particle results in a 5 MV power supply with no moving parts. For alpha particles, the voltage is halved. Consider also that the fuel mass is minimal, because of the high energy density. (Anywhere from 100000 to 1000000 times better than chemical fuel).
There are difficulties however. Alphas have very short range in solids, so the fuel layer would need to be very thin (1-2 microns). Beta's fare somewhat better in this regard. Furthermore, half of the particles will end up in their support electrode rather than at the collection electrode, resulting in loss of energy to heat. This heat has to be disposed of somehow (some can be converted into useful energy indirectly). Nevertheless, despite the inefficiencies, this is still way ahead of chemical propellant. Regards, Robin van Spaandonk http://users.bigpond.net.au/rvanspaa/ Competition provides the motivation, Cooperation provides the means.
