A Study on the Pressure Behavior Inside Propellant Line of Satellite

Abstract

One of the way to derive design parameters of the fuel feeding system in satellite propulsion system is to analyze unsteady flow of liquid propellant (hydrazine). During steady thruster firing the flow rate is constant: if a thruster valve is abruptly shut down among a set of thrusters, pressure spikes much higher than the initial tank pressure occur. This renders the fuel flow unsteady, and the fluid pressure and flow rate to oscillate. If the pressure spikes are high enough, there are possibilities that propellant explosively decomposes, thruster valves are damaged, and adiabatic detonation of the hydrazine propellant is potentially incurred. Reflected shockwaves could also affect the calibration and operation of the pressure transducers. These necessitate the analysis of unsteady flow in the propulsion system design, and pressure behavior inside the propellant line obtained through some governing parameter variation is presented in this work.

Keywords

• satellite
• propulsion system
• propellant
• pressure drop
• unsteady flow
• MOC