PSI - Issue 68

Evgeniia Georgievskaia et al. / Procedia Structural Integrity 68 (2025) 559–565 Evgeniia Georgievskaia / Structural Integrity Procedia 00 (2025) 000–000

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• duration of slow (from the present value ℓ up to ℓ th ) crack growth periods and rapid (from ℓ th up to ℓ cr ) in lifetime determining components; • threshold for sensitivity of non-destructive testing methods, used for monitoring the metal condition during operation; • predicted HU operating modes. 6. Conclusion The article justifies the importance of taking into account the influence of high-frequency loads on the degradation processes of HU components and proposes an engineering approach to the estimation of HU’s lifetime under actual operation. The proposed approach allows for adequate prediction of the lifetime-determining component destruction time considering every aspect of the HU design and operating modes and the combined effect of low-frequency and high frequency loads on crack growth rates. This approach does not place high demands on computing equipment, cost and time of numerical simulation procedures giving a good engineering estimate of the residual lifetime in terms of crack length. For practical purposes, the crack length can be converted into residual lifetime for each specific HU operation scenario Т res (hours). The proposed approach may be a convenient tool to predict the time needed for repair or replacement of worn components. Acknowledgements The presented results were obtained as part of research work with co-financing from the Foundation for Assistance to Small Innovative Enterprises in Science and Technology (FASIE), Russia (grants No. 3288ГС1/55639, No. 4373ГС2/55639), as well as with technical and financial support from the Skolkovo Innovation center. Vagnoni, E., Gezer, D., Anagnostopoulos, I., Cavazzini, G., Doujak, E., Hočevar, M., Rudolf, P., 2023. The new role of sustainable hydropower in flexible energy systems and its technical evolution through innovation and digitalization. In Proc of the 36th Int Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems (ECOS, pp. 1767-1776. Jamali, R., Sohani, A., Hemmatpour, K., Behrang, M., & Ghobeity, A., 2022. Experimental study of pressure pulsation in a large-scale hydropower plant with Francis turbine units and a common penstock. Energy Conversion and Management: X 16, 100308. Goyal, R., & Gandhi, B. K., 2018. Review of hydrodynamics instabilities in Francis turbine during off-design and transient operations. Renewable energy 116, 697-709. Mohanta, R. K., Chelliah, T. R., Allamsetty, S., Akula, A., & Ghosh, R., 2017. Sources of vibration and their treatment in hydro power stations-A review. Engineering science and Technology, an international journal 20(2), 637-648. Liu, C., Chen, T., Kang, W., Kang, J., Zhou, L., Tao, R., & Wang, Z., 2023. Study on pressure pulsation and force characteristics of Kaplan turbine. Water 15(13), 2421. Egusquiza, E., Valero, C., Presas, A., Huang, X., Guardo, A., & Seidel, U., 2016. Analysis of the dynamic response of pump-turbine impellers. Influence of the rotor. Mechanical systems and signal processing 68, 330-341. Ru, S, Zhang, S, Zhou, K, Huang, X, Huang, W, Wang, Z., 2023. Numerical Study on the Flow and Structural Characteristics of a Large High Head Prototype Pump-Turbine under Different Operating Conditions. Processes 11(10): 2970. BS 7910: 2019 Guide to methods for assessing the acceptability of flaws in metallic structures. Makhutov, N., Petrenia, Y., Lepikhin, A., Moskvichev, V., Gadenin, M., & Tchernyaev, A., 2020. Laboratory, Bench, and Full-Scale Researches of Strength, Reliability, and Safety of High-Power Hydro Turbines. In Probability, Combinatorics and Control, pp. 35-52. Liu, X.; Luo, Y.; Wang, Z., 2016.A review on fatigue damage mechanism in hydro turbines. Renew. Sustain. Energy Rev. 54, 1–14. Georgievskaia, E., 2019. Hydraulic turbines lifetime in terms of fracture mechanics. Engineering Failure Analysis 105, 1296-1305. References International Hydropower Association (IHA), 2023 World Hydropower Outlook. Opportunities to advance net zero https://indd.adobe.com/view/4201016f-a51a-4f6f-998b-ec85219d1dfd .