SONIC BOOM ANALYSIS UNDER ATMOSPHERIC UNCERTAINTIES BY A NON-INTRUSIVE POLYNOMIAL CHAOS METHOD

SONIC BOOM ANALYSIS UNDER ATMOSPHERIC UNCERTAINTIES BY A NON-INTRUSIVE POLYNOMIAL CHAOS METHOD

Shimoyama, K.; Ono, D.; Hashimoto, A.; Jeong, S.; Obayashi, S.

Full Article:

This study performed the sonic boom analysis considering atmospheric uncertainties at low computational costs. Non-intrusive polynomial chaos (NIPC) method was applied to the sonic boom analysis method solving an augmented Burgers equation. NIPC can approximate statistical behavior under uncertainties from a few samples. The augmented Burgers equation can consider the rise time of sonic boom unlike the waveform parameter method, which is commonly used for sonic boom analysis. Compared to Monte Carlo (MC) method, NIPC offered equivalent accuracy for the present sonic boom analysis even with much smaller sample size. It is confirmed that this method is adequate for practical use. In addition, the present simulation results revealed that temperature uncertainty has an impact on the local rise in sonic boom pressure, and humidity uncertainty has an impact on the entire sonic boom waveform, while wind uncertainty has almost no impact. This is because temperature uncertainty affects thermal viscosity, and humidity uncertainty affects relaxation, while the present study assumed that wind direction was uniform within each atmospheric layer.

This study performed the sonic boom analysis considering atmospheric uncertainties at low computational costs. Non-intrusive polynomial chaos (NIPC) method was applied to the sonic boom analysis method solving an augmented Burgers equation. NIPC can approximate statistical behavior under uncertainties from a few samples. The augmented Burgers equation can consider the rise time of sonic boom unlike the waveform parameter method, which is commonly used for sonic boom analysis. Compared to Monte Carlo (MC) method, NIPC offered equivalent accuracy for the present sonic boom analysis even with much smaller sample size. It is confirmed that this method is adequate for practical use. In addition, the present simulation results revealed that temperature uncertainty has an impact on the local rise in sonic boom pressure, and humidity uncertainty has an impact on the entire sonic boom waveform, while wind uncertainty has almost no impact. This is because temperature uncertainty affects thermal viscosity, and humidity uncertainty affects relaxation, while the present study assumed that wind direction was uniform within each atmospheric layer.

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DOI: 10.5151/meceng-wccm2012-16766

Referências bibliográficas

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• [7] Uncertainty Quantification in Computational Fluid Dynamics, RTO-AVT-VKI Lecture, 2011.

Como citar:

Shimoyama, K.; Ono, D.; Hashimoto, A.; Jeong, S.; Obayashi, S.; "SONIC BOOM ANALYSIS UNDER ATMOSPHERIC UNCERTAINTIES BY A NON-INTRUSIVE POLYNOMIAL CHAOS METHOD", p-342-350. In: In Proceedings of the 10th World Congress on Computational Mechanics [= Blucher Mechanical Engineering Proceedings, v. 1, n. 1]. São Paulo: Blucher, 2014.
ISSN 23580828, DOI 10.5151/meceng-wccm2012-16766