Steady and Transient CFD Analysis of a Vertical Axis Ocean Current Turbine
Downloads
Vertical-axis turbines (VATs) are a promising hydrokinetic technology for harvesting renewable energy from ocean currents. Still, their performance depends strongly on design parameters and flow interaction at different azimuthal angles. This study evaluates the performance of a VAT using computational fluid dynamics (CFD) simulations carried out under both steady-state and transient flow conditions. ANSYS CFX is used in the steady-state analysis to estimate torque and power output at various flow velocities and rotational speeds (RPM). At the same time, ANSYS Fluent is applied in the transient analysis to examine time-dependent torque behavior and azimuthal effects under unsteady flow. The steady-state results show that torque and power increase with higher flow velocity and rotational speed, reaching maximum values of 37,079 Nm and 291.86 kW at 4 m/s and 40 RPM. The transient results indicate periodic torque oscillations that become more stable at higher flow velocities, with peak turbine efficiency at 3 m/s, followed by a decrease at 4 m/s due to possible hydrodynamic losses. These findings provide clearer insight into VAT performance under realistic operating conditions and may support future efforts to improve hydrokinetic turbine design.
Downloads
[1] Finkl, C. W., & Charlier, R. (2009). Electrical power generation from ocean currents in the Straits of Florida: Some environmental considerations. Renewable and Sustainable Energy Reviews, 13(9), 2597–2604. doi:10.1016/j.rser.2009.03.005.
[2] Ponta, F. L., & Jacovkis, P. M. (2008). Marine-current power generation by diffuser-augmented floating hydro-turbines. Renewable Energy, 33(4), 665–673. doi:10.1016/j.renene.2007.04.008.
[3] Nunez, E. E., García González, D., López, O. D., Casas Rodríguez, J. P., & Laín, S. (2025). Fluid–Structure Interaction of a Darrieus-Type Hydrokinetic Turbine Modified with Winglets. Journal of Marine Science and Engineering, 13(3), 548. doi:10.3390/jmse13030548.
[4] Hantoro, R., Prananda, J., Mahmashani, A. W., Septyaningru, E., & Imanuddin, F. (2018). Performance investigation of an innovative Vertical Axis Hydrokinetic Turbine - Straight Blade Cascaded (VAHT-SBC) for low current speed. Journal of Physics: Conference Series, 1022(1), 12022. doi:10.1088/1742-6596/1022/1/012022.
[5] Velásquez, L., Rengifo, J., Saldarriaga, A., Rubio-Clemente, A., & Chica, E. (2025). Optimization of Vertical-Axis Hydrokinetic Turbines: Study of Various Geometric Configurations Using the Response Surface Methodology and Multi-Criteria Decision Matrices. Processes, 13(7), 1950. doi:10.3390/pr13071950.
[6] Inácio, R. G. da S., da Rosa, I. A., Avila, V. H., Rocha, L. A. O., Isoldi, L. A., Dias, G. da C., Gonçalves, R. A. A. C., & dos Santos, E. D. (2025). Numerical Investigation of Hybrid Darrieus/Savonius Vertical Axis Wind Turbine Subjected to Turbulent Airflows. Journal of Marine Science and Engineering, 13(10), 1979. doi:10.3390/jmse13101979.
[7] Ghafoorian, F., Hosseini Rad, S., & Moghimi, M. (2025). Enhancing Self-Starting Capability and Efficiency of Hybrid Darrieus–Savonius Vertical Axis Wind Turbines with a Dual-Shaft Configuration. Machines, 13(2), 87. doi:10.3390/machines13020087.
[8] Prasanna Vasan, V., VB, S. N., Alwin Thomson, A., Lakshmi Balaji, S., Dhatchna Moorthy, K., Subramania Pillai, S., ... & Nadaraja Pillai, S. (2025). Numerical simulation on the dynamic characteristics of VAWT with different cavity layouts. International Journal of Numerical Methods for Heat & Fluid Flow, 35(10), 3605-3635. doi:10.1108/HFF-10-2024-0803.
[9] Wong, K. H., Lee, K. Y., Ng, J. H., Wang, X. H., & Fazlizan, A. (2025). The effects of inertia on a straight-bladed vertical axis wind turbine. IOP Conference Series: Earth and Environmental Science, 1500(1), 12005. doi:10.1088/1755-1315/1500/1/012005.
[10] Shanab, B., & Untaroiu, A. (2025). Enhancing Dual-Rotor Vertical Axis Wind Turbines With Auxiliary Augmentation: Impact of Deflector Angle Orientation. Journal of Solar Energy Engineering , 147(6), 4069863. doi:10.1115/1.4069863.
[11] Kord, K., & Bazargan, M. (2024). Numerical Investigation on J-Shaped Straight-Bladed Darrieus Vertical Axis Wind Turbines Equipped with Gurney Flaps. International Journal of Energy Research, 8992210. doi:10.1155/2024/8992210.
[12] Prabowoputra, D. M., Prabowo, A. R., Yaningsih, I., Tjahjana, D. D. D. P., Laksono, F. B., Adiputra, R., & Suryanto, H. (2023). Effect of Blade Angle and Number on the Performance of Bánki Hydro-Turbines: Assessment using CFD and FDA Approaches. Evergreen, 10(1), 519–530. doi:10.5109/6782156.
[13] Stoessel, L., & Nilsson, H. (2015). Steady and unsteady numerical simulations of the flow in the Tokke Francis turbine model, at three operating conditions. Journal of Physics: Conference Series, 579(1), 12011. doi:10.1088/1742-6596/579/1/012011.
[14] Zimmer, G. (2008). Modelling and simulation of steam turbine processes: Individual models for individual tasks. Mathematical and Computer Modelling of Dynamical Systems, 14(6), 469–493. doi:10.1080/13873950802384001.
[15] Huang, W. D., Fan, H. G., & Chen, N. X. (2012). Transient simulation of hydropower station with consideration of three-dimensional unsteady flow in turbine. IOP Conference Series: Earth and Environmental Science, 15(5), 52003. doi:10.1088/1755-1315/15/5/052003.
[16] Rezaeiha, A., Montazeri, H., & Blocken, B. (2018). Towards accurate CFD simulations of vertical axis wind turbines at different tip speed ratios and solidities: Guidelines for azimuthal increment, domain size and convergence. Energy Conversion and Management, 156, 301–316. doi:10.1016/j.enconman.2017.11.026.
[17] Revuz, J., Hargreaves, D. M., & Owen, J. S. (2012). On the domain size for the steady-state CFD modelling of a tall building. Wind and Structures, 15(4), 313–329. doi:10.12989/was.2012.15.4.313.
[18] Ghasemian, M., Ashrafi, Z. N., & Sedaghat, A. (2017). A review on computational fluid dynamic simulation techniques for Darrieus vertical axis wind turbines. Energy Conversion and Management, 149, 87–100. doi:10.1016/j.enconman.2017.07.016.
[19] Stival, L. J. L., Brinkerhoff, J. R., Vedovotto, J. M., & de Andrade, F. O. (2022). Wake modeling and simulation of an experimental wind turbine using large eddy simulation coupled with immersed boundary method alongside a dynamic adaptive mesh refinement. Energy Conversion and Management, 268, 115938. doi:10.1016/j.enconman.2022.115938.
[20] Wang, L., Dong, M., Yang, J., Wang, L., Chen, S., Duić, N., Joo, Y. H., & Song, D. (2024). Wind turbine wakes modeling and applications: Past, present, and future. Ocean Engineering, 309, 118508. doi:10.1016/j.oceaneng.2024.118508.
[21] Lintermann, A. (2020). Computational meshing for CFD simulations. Clinical and Biomedical Engineering in the Human Nose: A Computational Fluid Dynamics Approach. Springer Singapore, Singapore. doi:10.1007/978-981-15-6716-2_6.
[22] diputra, R., Budisetyawan, D., Firdaus, N., Prabowo, A. R., Erwandi, & Rasgianti. (2024). Dynamic Characteristics of Trimaran Type Floating Ocean Current Power Plant. 2024 International Conference on Technology and Policy in Energy and Electric Power (ICTPEP), 140–144. doi:10.1109/ICT-PEP63827.2024.10733472.
[23] Fertahi, S. ed D., Belhadad, T., Kanna, A., Samaouali, A., Kadiri, I., & Benini, E. (2023). A Critical Review of CFD Modeling Approaches for Darrieus Turbines: Assessing Discrepancies in Power Coefficient Estimation and Wake Vortex Development. Fluids, 8(9), 242. doi:10.3390/fluids8090242.
[24] Huang, H., Sun, T., Zhang, G., Li, D., & Wei, H. (2019). Evaluation of a developed SST k-Ω turbulence model for the prediction of turbulent sl-ot jet impingement heat transfer. International Journal of Heat and Mass Transfer, 139, 700–712. doi:10.1016/j.ijheatmasstransfer.2019.05.058.
[25] Mohamed, M. H., Ali, A. M., & Hafiz, A. A. (2015). CFD analysis for H-rotor Darrieus turbine as a low speed wind energy converter. Engineering Science and Technology, an International Journal, 18(1), 1–13. doi:10.1016/j.jestch.2014.08.002.
[26] Longest, P. W., & Vinchurkar, S. (2007). Effects of mesh style and grid convergence on particle deposition in bifurcating airway models with comparisons to experimental data. Medical Engineering & Physics, 29(3), 350–366. doi:10.1016/j.medengphy.2006.05.012.
[27] Paz, C., Suárez, E., Conde, M., & Vence, J. (2020). Development of a Computational Fluid Dynamics Model for Predicting Fouling Process Using Dynamic Mesh Model. Heat Transfer Engineering, 41(2), 199–207. doi:10.1080/01457632.2018.1522108.
[28] Zukas, J. A., & Scheffler, D. R. (2000). Practical aspects of numerical simulations of dynamic events: Effects of meshing. International Journal of Impact Engineering, 24(9), 925–945. doi:10.1016/S0734-743X(00)00012-9.
[29] Gobat, J. I., & Grosenbaugh, M. A. (2006). Time-domain numerical simulation of ocean cable structures. Ocean Engineering, 33(10), 1373–1400. doi:10.1016/j.oceaneng.2005.07.012.
[30] Welahettige, P., & Vaagsaether, K. (2018). Comparison of OpenFOAM and ANSYS Fluent. Proceedings of the 9th EUROSIM Congress on Modelling and Simulation, EUROSIM 2016, the 57th SIMS Conference on Simulation and Modelling SIMS 2016, 142, 1005–1012. doi:10.3384/ecp171421005.
[31] Xiao, Q., Liu, W., & Incecik, A. (2013). Flow control for VATT by fixed and oscillating flap. Renewable Energy, 51, 141–152. doi:10.1016/j.renene.2012.09.021.
[32] Arini, N. R., Turnock, S. R., & Tan, M. (2022). The Effect of Trailing Edge Profile Modifications to Fluid-Structure Interaction of a Vertical Axis Tidal Turbine Blade. International Journal of Renewable Energy Development, 11(3), 725–735. doi:10.14710/ijred.2022.44669.
[33] Ayachi Amar, A., Berkache, A., Amroune, S., Noura, B., & Boumehani, A. (2022). Numerical Modeling of Dynamic Stall in a Vertical Axis Wind Turbine. Academic Journal of Manufacturing Engineering, 20(4), 135–143.
[34] Fernández-Jiménez, A., Álvarez-Álvarez, E., López, M., Fouz, M., López, I., Gharib-Yosry, A., Claus, R., & Carballo, R. (2021). Power performance assessment of vertical-axis tidal turbines using an experimental test rig. Energies, 14(20), 6686. doi:10.3390/en14206686.
- This work (including HTML and PDF Files) is licensed under a Creative Commons Attribution 4.0 International License.



















