Test Bench for the Unsteady Characterization of a Pulsed Green Monopropellant Thruster

PulCheR is a R&D project funded by the European Union Seventh Framework Programme with the main aim of demonstrating the feasibility of a new propulsion concept in which the propellants are fed in the combustion chamber at low pressure and the thrust is generated by means of high frequency pulses. The characterization of this type of thruster has required to carefully design the test bench in order to allow the right assessment of the thruster performance. The unsteady behavior of the thruster has been the main difficulty during the design and the choice of transducers. The most difficult measurement concerns the assessment of the mass injected at each pulse inside the thruster. Because of this, two distinct test benches have been designed and two approaches at measuring the mass injected have been considered. The present article focuses on the challenges concerning the design of the test bench for the characterization of the PulCheR monopropellant thruster.