Energy-Based Acoustic Measurement System for Rocket Noise

Accurate estimates of the vibroacoustic loading placed on space vehicles and payloads during launch require knowledge of the rocket noise source properties. Given the extreme nature of acoustic environments near the plume, data sufficient to characterize the noise source region have been difficult to acquire. Without these data, structures may be designed to handle insufficient or excessive vibroacoustic loads, resulting in either an overbuilt structure (and extra weight), or an under-designed vibration isolation system that could result in damaged cargos. Current energy-based acoustic probe designs have limited frequency bandwidth due to physical limitations. A new set of probe designs is proposed that incorporate both a new physical probe design but also a more advanced signal processing methodology that will significantly increase the usable frequency bandwidth of the probes while reducing the manufacturing and maintenance costs of the probes. The probe system will also include the design of a complete data acquisition system capable of recording data under the harsh conditions present in typical rocket motor test firings.