The influence of gas-dynamic processes on acoustic radiation in the interaction of impinging jet with the flat plate
Heading:
| 1Nikolin, SO, 1Sokol, GI 1Oles Honchar National University of Dnipropetrovsk, Dnipro, Ukraine |
| Space Sci. & Technol. 2020, 26 ;(3):20-31 |
| https://doi.org/10.15407/knit2020.03.020 |
| Publication Language: Russian |
Abstract: The spacecraft launch is one of the most important phases of the flight missions since the complex gas-dynamic interactionprocesses of a high-temperature supersonic jet which is flowing from the nozzle of the propulsion system with the structural elements of the launchpad are typical for this phase of flight. These processes entail the occurrence of turbulent flows accompanied by shock waves, the waves’ discharge, and contact discontinuities. As a result, elements of the launch pad and the walls of the flame duct undergo intense gas-dynamic and thermal loads. Instabilities and transients generate acoustic and vibration fluctuations. The last ones affect the structural elements of ground structures, the state of the payload, and the ecosphere around the launch pad. Therefore, the correct prediction of these loads at the preliminary design phase of the rocket and launch facilities can significantly increase the strength and stability of the spacecraft elements, increase their reliability, as well as provide measures to reduce noise levels in the rocket launch area.
The objective of the study is the impact of the distance between the nozzle exit and a flat obstacle on the gas-dynamic characteristics of the impinging jet and the resulting acoustic radiation. The gas-dynamic processes that occur when a supersonic jet flows onto a barrier are described using the Navier-Stokes system equations. The equations express the laws of conservation of mass, momentum, and energy for an ideal gas. Calculation of acoustic processes was performed in two stages using the Fox Williams-Hawkings integral method and Fourier series expansions. At the first stage, the gas-dynamic problem was solved in a steady-state mode using the SST k- turbulence model. The second stage was acoustic in transient mode using the DES turbulence model. The results of calculations were some gas-dynamic and acoustic characteristics of the supersonic underexpanded jet flowing onto a flat plate presented in the form of diagrams and graphs. The results demonstrated that an increase in distance between the nozzle exit and the plate leads to the appearance of complex turbulent flows, which in turn cause the increase in acoustic radiation levels. This is due to the fact that oscillations of the turbulent sublayer and the presence of shock waves and rarefaction waves are the main sources of noise when a jet flows onto a flat plate. The intensity of noise sources also increases with increasing distance between the nozzle and the plate. However, if we consider the far acoustic field, changes in this distance weakly affect the overall sound pressure level possibly due to receivers are far outside the computational domain. In this case, the used FW-H method works worse. |
| Keywords: acoustic pressure, flat plate, Mach number, pressure coefficient, sound pressure level, underexpanded jet |
References:
1. Antsupov A. V., Blahosklonov V. I., Pimshtein V. H. (1973). The interaction of the overexpanded gas jet with a flat barrier. Scientific Notes TsAGI, 4, No. 1, 84-87 [in Russian].
2. Buhmastov M. V., Sidelnikov R. V. (2014). Development of methods for assessing the jet blast noise impact on the launch vehicle. Science of SUSU '14: 66 nauchnaia konferentsiia (15-17 aprelia 2014 hoda) - 66th Scientific Conference (pp. 108-112). Cheliabinsk: Izdatelskii tsentr YuUrHU [in Russian].
3. Hinzburh I. P., Sokolov E. I., Uskov V. N. (1976). Types of wave structure in the interaction of an underexpanded jet with an infinite flat barrier. Applied mechanics and technical physics, No. 1, 45-50 [in Russian].
https://doi.org/10.1007/BF00857748
4. Hubanova O. I., Lunev V. V., Plastinina L. I. (1971). On the central separated-flow region in the interaction of a supersonic underexpanded jet with a barrier. Izv. AN SSSR, MZhH. - The Academy of Sciences of USSR Review, FM, No. 2, 135-138 [in Russian].
5. Kudin O. K., Nesterov Yu. N., Tokarev O. D., Flaksman Ya. Sh. (2013). Experimental study of the flow of high-temperature jet of dusty gas on the barrier. Scientific Notes TsAGI, 44, No. 6, 105-115 [in Russian].
https://doi.org/10.1615/TsAGISciJ.2014011135
6. Melnikova M. F., Nesterov Yu. N. (1971). The impact of a supersonic off-design jet on a flat barrier normal to the axis of the jet. Scientific Notes TsAGI, 2, No. 5, 105-108 [in Russian].
7. Naberezhnova H. V., Nesterov Yu. N. (1982). Unsteady flow in the region of interaction of an underexpanded jet with a barrier. Scientific Notes TsAGI, 13, No. 4, 134-140 [in Russian].
8. Nikolin S. A., Prihodko A. A. (2018). Numerical simulation of the interaction of an underexpanded supersonic gas jet with a flat barrier. Reporter of the Dnipro University, 26, No. 4, 73-80 [in Russian].
9. Poliakova N. S. (2012). The accuracy evaluation of methods for calculating aerodynamic noise using the ANSYS FLUENT software. Master's thesis. Saint Petersburg [in Russian].
10. Akamine M., Okamoto K., Gee K. L., Neilsen T. B., Teramoto S., Okunuki T., Tsutsumi S. (2018). Effect of nozzle-plate distance on acoustic phenomena from supersonic impinging jet. AIAA J. 56, No. 5, 1943-1952.
https://doi.org/10.2514/1.J056504
11. Alvi F. S., Ladd J. A., Bower W. W. (2002). Experimental and computational investigation of supersonic impinging jets. AIAA J. 40, 599-609.
https://doi.org/10.2514/2.1709
12. ANSYS Inc., Canonsburg, PA. Product Documentation Release 14.0, 2010.
13. Bahman-Jahrom I., Ghorbanian K., Ebrahimi M. (2019). Experimental investigation on acoustic wave generation due to supersonic hot jet impingement on an inclined flat plate. J. Appl. Fluid Mech. 12, No. 4, 1063-1072.
https://doi.org/10.29252/jafm.12.04.29261
14. Dewan Y. (2013). A preliminary study of acoustic prediction technology based on detached eddy simulations for supersonic jets impinging on flat plates. Master's thesis. Daytona Beach.
https://doi.org/10.2514/6.2013-3097
15. Fukuda K., Tsutsumi S., Fujii K., Ui K., Ishii T., Oinuma H., Kazawa J., et al. (2009). Acoustic measurement and prediction of solid rockets in static firing tests // 15th AIAA/CEAS Aeroacoustics Conference (30th AIAA Aeroacoustics Conf.) (May 11-13, 2009). - Miami, Florida, 2009.
https://doi.org/10.2514/6.2009-3368
16. Acoustic loads generated by the propulsion system (1971). Hampton, Virginia: NASA.
17. Bahman-Jahrom I., Ghorbanian K., Ebrahimi M. (2019). Experimental investigation on acoustic wave generation due to supersonic hot jet impingement on an inclined flat plate. J. Appl. Fluid Mech. 12, No. 4, 1063-1072.
https://doi.org/10.29252/jafm.12.04.29261
18. Worden T. J., Gustavsson J. P. R., Shih Ch., Alvi F. S. (2013). Acoustic measurements of high-temperature supersonic impinging jets in multiple configurations. 19th AIAA/CEAS Aeroacoustics Conf. (May 27-29, 2013). Berlin, 2013.
https://doi.org/10.2514/6.2013-2187