Unsteady Pressure Acquisition on the 1.75% Scale SLS Block 1B Cargo Liftoff Configuration

Time-varying pressure on the core of the Space Launch System (SLS) Block 1B Cargo vehicle was acquired using instrumentation typically used for steady, time averaged pressure. Resono Pressure Systems, Inc. in partnership with the University of Wyoming have developed a unique hardware and software system for measuring unsteady pressure, which was implemented in a large-scale wind tunnel test through a nonreimbursable Space Act Agreement with NASA. The technique was applied to 12 pressure ports on the 1.75% scale SLS wind tunnel model. Tubing lengths of approximately 14 inches separated the pressure transducer module from the pressure taps on the model surface, and surface-mount validation sensors (Kulites) were installed in close proximity to 5 of the 12 pressure ports. Up to about 500 Hz, the frequency response of pressure fluctuations agreed to within 1 dB of amplitude and 10° of phase difference compared to the simultaneously-acquired surface-mount transducers. Sample results using the reconstructed pressure from the full azimuthal ring of taps are presented.