Low thrust and low power propulsion systems options for small satellites

<p>The present work focuses on the study of low thrust propulsion systems. Cold gas, thermal and monopropellant systems with a blow down depressurisation mode have been taken in consideration in this study. Most of propellants that can be used for small satellite propulsion systems were selected here in order to give the propulsion engineer many propellant options with a good idea about the performance of each propellant, and this is important to make a good trade-off during the system design. For cold gas and thermal propulsion, the propellants taken into account in this study are: Oxygen (O2), Nitrogen (N2), Hydrogen (H2), Carbon dioxide (CO2), Helium (He), Xenon (Xe), Methane (CH4), Propane (C3H8) and Butane (C4H10). The purpose of this part is to determine numerically the temperature after heating, specific impulse (Isp), C* and isentropic parameter (γ) as a function of the consumed heat (which represents the power of the heater). After heating, 2D axisymmetric fluid flow (with variable specific heat Cp(T) ) inside the nozzle was selected in this study. For monopropellants, the decomposition of hydrazine (N2H4), hydrogen peroxide (H2O2) and nitrous oxide (N2O) have been studied numerically to determine all the thermochemical and performance parameters, using 2D frozen flow (with Cp(T)) inside the nozzle. As an application, 15 watts butane thruster and hydrogen peroxide monopropellant thruster have been analysed to estimate the performance (Isp). The results obtained were compared with experimental results; the comparison shows good agreement where the difference is less than 4 %.</p>