ColdGas Simulator Rocket Vibration Study

There is considerable benefit to be obtained from a cold-flow experimental simulation of an axially vibrating rocket motor chamber. While the base pressure and temperature of the internal gas will be considerably lower than that for a solid, hybrid or liquid rocket engine, there are various flow and structural parameters that can be correlated between the two cases. The CGS/RVS, employing an ABS pipe attached to an axial shaker, is being developed for assessment of axial pressure wave strength resulting from various axial structural oscillation frequencies and displacement amplitudes. Radial vibration of the structure resulting from the passage of an axial pressure wave is an additional factor of interest. High-frequency pressure transducers and accelerometers positioned at various positions provide the required experimental data. This information can be used to validate CFD code results, and identify discrepancies due to factors not modelled in the numerical simulations. Correlation to potential problems that might be encountered by actual motors undergoing free or forced structural oscillations can then be made.