Mathematics

New Aerospace and Defense Research from University of Toulouse Discussed

  2012 APR 24 - (VerticalNews.com) -- According to the authors of recent research published in the Journal of Propulsion and Power, "The Hall-effect thruster application to compensate the atmospheric drag force for a spacecraft in a low orbit altitude is not possible because a large amount of propellant must he stored to compensate for the continuous force acting on the spacecraft for a long time, which increases the weight of the spacecraft and mission requirements. The goal of this study is to analyze, with the help of simple analytic scaling laws and a two-dimensional hybrid model of a Hall-effect thruster, the possibility of using the ambient atmospheric gas as propellant for a spacecraft or space vehicle positioned in the Earth's ionosphere."

  "In comparison with xenon propellant, the length of the ionization layer increases due to less favorable ionization cross sections of the atmospheric gases. The consequence is that the channel geometry and magnetic field strength adopted for xenon are no longer suitable for low-mass propellants. Analytical work and calculations show that a reduced magnetic field and a longer channel length lead to a benefit in the ionization of atmospheric gases. Calculations also show that propellant mass flow rates of about 3 mg. s(-1) for O and N-2 are necessary to produce a thrust of 20 mN to counteract the drag force at an altitude of 250 km. At this altitude, the density of molecules/atoms of ambient atmospheric gas is so rare that the incoming atmosphere flow inside the thruster channel is insufficient to generate the required thrust," wrote L. Garrigues and colleagues, University of Toulouse.

  The researchers concluded: "Results indicate that a complex system, based on a collector, tank, pump, and compressor, is necessary to reach sufficient pressure inside the thruster channel."

  Garrigues and colleagues published their study in the Journal of Propulsion and Power (Computational Study of Hall-Effect Thruster with Ambient Atmospheric Gas as Propellant. Journal of Propulsion and Power, 2012;28(2):344-354).

  For additional information, contact L. Garrigues, Univ Toulouse, F-31062 Toulouse, France.

  The publisher's contact information for the Journal of Propulsion and Power is: Amer Inst Aeronaut Astronaut, 1801 Alexander Bell Drive, Ste 500, Reston, VA 22091-4344, USA.

  Keywords: City:Toulouse, Country:France, Region:Europe, Mathematics, Aerospace and Defense

  This article was prepared by VerticalNews Mathematics editors from staff and other reports. Copyright 2012, VerticalNews Mathematics via VerticalNews.com.