REDUCING SHIP NOISE POLLUTION THROUGH SPECTRAL IDENTIFICATION OF DIESEL GENERATOR VIBROACOUSTIC PROCESSES
https://doi.org/10.33815/2313-4763.2026.1.32.071-086
Abstract
The paper presents the results of an experimental vibroacoustic investigation of a marine diesel generator operating under three characteristic conditions: idle running mode, partial load of 18 kW, and working load of 36 kW. The relevance of the study is associated with current international requirements aimed at reducing underwater radiated noise generated by ships, improving the environmental safety of maritime transport, and enhancing onboard diagnostic methods for marine power plants. Particular attention is devoted to low-frequency spectral components related to shaft rotational dynamics, cyclic irregularity, structural vibration transmission, and tonal acoustic excitation. Experimental measurements included simultaneous acquisition of acoustic and vibration signals obtained from low-frequency acoustic channels and structural vibration sensors installed on the diesel-generator system. Digital signal processing was performed using the Discrete Fourier Transform and Fast Fourier Transform algorithms with subsequent narrowband spectral analysis in the frequency range of 0-200 Hz. Additional processing included RMS evaluation, harmonic order identification, and comparative analysis of acoustic and vibration spectra. The results demonstrated that the most informative spectral components correspond to frequencies of 25.1, 50.2, 100.2, 150.4, and 175.5 Hz. These frequencies are associated with shaft rotational orders, piston-group inertial forces, cyclic combustion irregularity, torsional oscillations, and structural resonance processes. It was established that the 18 kW operating condition provides the most balanced spectral structure, while the 36 kW mode is characterized by increased harmonic saturation and higher rotational non-uniformity. The proposed integrated vibroacoustic approach can be applied for onboard condition monitoring of marine power plants, early detection of developing mechanical defects, evaluation of structural vibration processes, and operational reduction of ship-generated underwater radiated noise.
References
2. Wang, L. S., Robinson, S. P., Theobald, P. D., Lepper, P. A., Hayman, G., & Humphrey, V. F. (2013). Measurement of radiated ship noise. Proceedings of Meetings on Acoustics, 17, 070091. https://doi.org/10.1121/1.4792663.
3. Gloza, I. (2008). Vibration and radiated noise of a small ship. Hydroacoustics, 11. https://bibliotekanauki.pl/articles/331545.
4. International Organization for Standardization (2000). ISO 6954:2000. Mechanical vibration – Guidelines for the measurement, reporting and evaluation of vibration with regard to habitability on passenger and merchant ships. ISO. https://www.iso.org/standard/28883.html.
5. International Organization for Standardization (2016). ISO 20283-5:2016. Mechanical vibration – Measurement of vibration on ships – Part 5: Guidelines for measurement, evaluation and reporting of vibration with regard to habitability on passenger and merchant ships. ISO. https://www.iso.org/standard/68125.html.
6. International Organization for Standardization (2016). ISO 17208-1:2016. Underwater acoustics – Quantities and procedures for description and measurement of underwater sound from ships – Part 1: Requirements for precision measurements in deep water used for comparison purposes. ISO. https://www.iso.org/standard/62408.html.
7. American Bureau of Shipping (2017). Guidance notes on noise and vibration control for inhabited spaces. ABS. https://ww2.eagle.org/content/dam/eagle/rules-and-guides/current/other/ 209_noisevibrationcontrolinhabitedspaces/Noise_and_Vibration_GN_e-Sept17.pdf.
8. American Bureau of Shipping (2006). Guidance notes on ship vibration. ABS. https://www.vibrationdata.com/tutorials/abs_ship_vibration.pdf.
9. Kluczyk, M., & Grządziela, A. (2019). Marine diesel engine common rail injectors monitoring with vibration parameters. Diagnostyka, 20(3), 37–44. https://doi.org/10.29354/diag/109793.
10. Varbanets, R., Minchev, D., Kucherenko, Yu., Zalozh, V., Kyrylash, O., & Tarasenko, T. (2024). Methods of real-time parametric diagnostics for marine diesel engines. Polish Maritime Research, 31(3), 71–84. https://doi.org/10.2478/pomr-2024-0037.
11. Varbanets, R. A., Minchev, D. S., Kucherenko, Yu. M., & Zalozh, V. I. (2024). Real-time parametric diagnostics of marine diesel engines [Parametrychna diahnostyka sudnovykh dyzelnykh dvyhuniv u rezhymi realnoho chasu]. Dvyhuny vnutrishnoho zghoriannia, 1, 69–76. https://doi.org/10.20998/0419-8719.2024.1.09 [in Ukrainian].
12. Kluczyk, M., & Grządziela, A. (2020). Vibration diagnostics of marine diesel engines malfunctions connected with injection pumps supported by modelling. Naše More, 67(3), 209–216. https://doi.org/10.17818/NM/2020/3.4. 13. Drewing, S., & Witkowski, K. (2021). Spectral analysis of torsional vibrations measured by optical sensors, as a method for diagnosing injector nozzle coking in marine diesel engines. Sensors, 21(3), 775. https://doi.org/10.3390/s21030775.
14. Minchev, D., Varbanets, R., & Kucherenko, Yu. (2024). Vibroacoustic diagnostic features of marine diesel engines under transient operating conditions. Journal of Marine Science and Engineering, 12(4), 652. https://doi.org/10.3390/jmse12040652.
15. Kucherenko, V. Yu., & Bulgakov, M. P. (2025). Modern methods and research directions for reducing ship hydroacoustic noise [Suchasni metody ta napriamky doslidzhen shchodo znyzhennia rivnia hidroakustychnykh shumiv sudna]. Rozvytok transportu, 1(24), 31–43. https://doi.org/10.33082/td.2025.1-24.03 [in Ukrainian].
16. Kucherenko, V. (2025). The impact of proactive ship handling on reducing the ship’s vibration and hydroacoustic noise. Visnyk Pryazovskoho derzhavnoho tekhnichnoho universytetu. Seriia: Tekhnichni nauky, 51, 263–274. https://doi.org/10.31498/2225-6733.51.2025.344963.
17. Welch, P. (1967). The use of fast Fourier transform for the estimation of power spectra: A method based on time averaging over short, modified periodograms. IEEE Transactions on Audio and Electroacoustics, 15(2), 70–73. https://doi.org/10.1109/TAU.1967.1161901.
18. International Organization for Standardization (2016). ISO 20816-1:2016. Mechanical vibration – Measurement and evaluation of machine vibration – Part 1: General guidelines. ISO. https://www.iso.org/standard/63180.html.
