Back to Blog
Helium electric conductivity6/12/2023 ![]() System parameters and estimated operating ranges are summarized. Several different probes will be designed and implemented to verify the plasma kinetics model. Experiments will simulate the neutron generated plasma modeled by Bitteker, which takes into account the products of thermal neutron absorption in He-3, and includes various ion species in estimating the conductivity of the resulting plasma. The equivalent neutron flux that would produce the same ionization fraction in helium is 1x10(exp 12) n/sq cm/s. Spreading the electron beam over a four inch diameter window results in an electron flux of 1.5x 10(exp 13) e/sq cm/s. Initial experiments will utilize a 50 keV electron gun that can operate at up to a current of 200 micro A. These experiments will be focused on diagnosis of the plasma in a virtually static system results will be applied to future tests with a MHD system. High energy electrons will be used to simulate the effects of neutron-induced ionization of helium gas to produce a plasma. An experimental facility has been constructed at the Propulsion Research Center at the NASA Marshall Space Flight Center, using helium as the test fluid. Calculations suggest that nuclear-enhanced electrical conductivity increases as the neutron flux increases conductivity of pure He-3 greater than 10 mho/m may be achievable if exposed to a flux greater than 10(exp 12) neutrons/cm2/s.) However, this remains to be demonstrated experimentally. Although traditional MHD flows depend on thermal ionization to enhance the electrical conductivity, ionization due to nuclear interactions may achieve a comparable or improved conductivity enhancement while avoiding many of the limitations inherent to thermal ionization. The efficiency of a MHD generator is strongly dependent on the electrical conductivity of the fluid that passes through the generator power density increases as fluid conductivity increases. Robe Development for Electrical Conductivity Analysis in an Electron Gun Produced Helium Plasma The use of magnetohydrodynamic (MHD) power conversion systems, potentially coupled with a fission power source, is currently being investigated as a driver for an advanced propulsion system, such as a plasma thruster.
0 Comments
Read More
Leave a Reply. |