Session

session4

Location

Space Dynamics Laboratory, Auditorium Rm A

Start Date

5-9-2022 10:50 AM

End Date

5-9-2022 11:00 AM

Description

The Delta IV Heavy is an orbital heavy class launch vehicle that has been in operation since 2004. In this study, the overall sound power level and other acoustic properties of the Delta IV Heavy launch vehicle will be calculated and analyzed. Five data acquisition systems with a wide frequency bandwidth were placed in a far-field arc around a 2021 launch. Using a weighted mean to compare results across stations, a maximum overall sound pressure level (OASPL) of 140 dB and an average maximum polar directivity angle of 69 deg were calculated. An overall sound power level of 198 dB and radiation efficiency of 0.3% were also calculated. Given the asymmetry of the vehicle boosters, a preliminary investigation of the azimuthal directivity of the vehicle is explored with suggestions made for future studies. All determined source characteristics of the Delta IV Heavy vehicle are compared to prior launch vehicle acoustics studies, in order to identify useful models and methods for understanding rocket noise.

Available for download on Tuesday, May 09, 2023

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May 9th, 10:50 AM May 9th, 11:00 AM

Acoustic Analysis of the Delta IV Heavy Launch Vehicle

Space Dynamics Laboratory, Auditorium Rm A

The Delta IV Heavy is an orbital heavy class launch vehicle that has been in operation since 2004. In this study, the overall sound power level and other acoustic properties of the Delta IV Heavy launch vehicle will be calculated and analyzed. Five data acquisition systems with a wide frequency bandwidth were placed in a far-field arc around a 2021 launch. Using a weighted mean to compare results across stations, a maximum overall sound pressure level (OASPL) of 140 dB and an average maximum polar directivity angle of 69 deg were calculated. An overall sound power level of 198 dB and radiation efficiency of 0.3% were also calculated. Given the asymmetry of the vehicle boosters, a preliminary investigation of the azimuthal directivity of the vehicle is explored with suggestions made for future studies. All determined source characteristics of the Delta IV Heavy vehicle are compared to prior launch vehicle acoustics studies, in order to identify useful models and methods for understanding rocket noise.