Document Type : Original Article

Authors

1 Master of Science, Sea-Based Energy Research Group, Babol Noshirvani University of Technology,

2 Professor, Sea-Based Energy Research Group, Babol Noshirvani University of Technology, Babol, Iran

3 Assistant Professor, Sea-Based Energy Research Group, Babol Noshirvani University of Technology, Babol, Iran

10.22044/rera.2026.16520.1441

Abstract

The performance of tidal turbines hinges on geometric characteristics and wave-current properties. This study investigates the performance of a three-bladed, 1:6 scale horizontal axis tidal turbine (HATT), with a particular focus on the underexplored influence of flow direction—a critical factor for bi-directional tidal sites. The effects of various variables, including pitch angle, flow direction, electrical load, and wave-current interaction under different tip speed ratios, were systematically studied. Power and moment of force coefficients (Cp and Cm) alongside their TSRs were considered as the objective functions. The wave characteristics of the Khoran Strait were scaled using Froude methodology. The Cp and Cm at the optimal pitch angle range for downstream flow do not exceed a maximum increase of 6.5% compared to the no-wave modes. When the HATT operates at its optimum variables, the power coefficient increased by 35% compared to the lowest level. However, due to the generator's characteristics, the increase in power and moment of force follows a non-linear trend. The variations in Cp and Cm at different TSRs also form a parabolic pattern. A key novel contribution of this study is the comprehensive comparison of upstream versus downstream flow configurations, revealing that the turbine's power and moment of force coefficients in the upstream flow state increase by 36.1% and 18.1%, respectively, compared to the same pitch angles in the downstream flow state, due to the absence of the nacelle impeding the current. This finding provides crucial design guidance for bi-directional tidal turbine installations.

Keywords

Main Subjects

[1] Kharkeshi, B.A., et al., Measuring and investigating the effect of sloshing on the performance of an OWC wave energy converter by means of a novel experimental approach. Ocean Engineering, 2023. 275: p. 114130.
 
[2] Faudot, C. and O.G. Dahlhaug, Prediction of wave loads on tidal turbine blades. Energy Procedia, 2012. 20: p. 116-133.
 
[3] Liu, B. and S. Park, CFD Simulations of the Effects of Wave and Current on Power Performance of a Horizontal Axis Tidal Stream Turbine. Journal of Marine Science and Engineering, 2023. 11(2): p. 425.
 
[4] Gaurier, B., et al., Flume tank characterization of marine current turbine blade behaviour under current and wave loading. Renewable Energy, 2013. 59: p. 1-12.
 
[5] Zhou, J., et al., Research on Wake Field Characteristics and Support Structure Interference of Horizontal Axis Tidal Stream Turbine. Energies, 2023. 16(9): p. 3891.
 
[6] Watanabe, S., M.M. Kamra, and C. Hu, An experimental study of surface wave effects on two interacting tidal turbines. Journal of Marine Science and Technology, 2023. 28(2): p. 387-398.
 
[7] Nuernberg, M. and L. Tao, Experimental study of wake characteristics in tidal turbine arrays. Renewable energy, 2018. 127: p. 168-181.
 
[8] Okulov, V., et al., Experiments on line arrays of horizontal-axis hydroturbines. Renewable energy, 2021. 163: p. 15-21.
 
[9] Mycek, P., et al., Experimental study of the turbulence intensity effects on marine current turbines behaviour. Part I: One single turbine. Renewable Energy, 2014. 66: p. 729-746.
 
[10] Mycek, P., et al., Experimental study of the turbulence intensity effects on marine current turbines behaviour. Part II: Two interacting turbines. Renewable Energy, 2014. 68: p. 876-892.
 
[11] Druault, P. and G. Germain, Experimental investigation of the upstream turbulent flow modifications in front of a scaled tidal turbine. Renewable Energy, 2022. 196: p. 1204-1217.
 
[12] Magnier, M., et al., Experimental study of the shear flow effect on tidal turbine blade loading variation. Renewable Energy, 2022. 193: p. 744-757.
 
[13] Capone, A., et al., Impact of cavitation and inflow perturbation on the performance of a horizontal-axis tidal turbine. Journal of Ocean Engineering and Marine Energy, 2023. 9(4): p. 731-743.
 
[14] Muchala, S. and R.H. Willden, Influence of support structures on tidal turbine power output. Journal of Fluids and Structures, 2018. 83: p. 27-39.
 
[15] Mason-Jones, A., et al., Influence of a velocity profile & support structure on tidal stream turbine performance. Renewable energy, 2013. 52: p. 23-30.
 
[16] Shoukat, G., et al., Experimental investigation of the influence of mast proximity on rotor loads for horizontal axis tidal turbines. Renewable Energy, 2022. 200: p. 983-995.
 
[17] Van Benthem, M., et al. The influence of surface waves on tidal turbine performance characteristics. in AGU Fall Meeting Abstracts. 2012.
 
[18] Draycott, S., et al., Experimental assessment of tidal turbine loading from irregular waves over a tidal cycle. Journal of Ocean Engineering and Marine Energy, 2019. 5: p. 173-187.
 
[19] Eskandari Shal, J., R. Shafaghat, and B. Alizadeh Kharkeshi, Investigating air compressibility effects in numerical modeling of oscillating water column wave energy converters: a case study on performance and accuracy. Coastal Engineering Journal, 2025: p. 1-19.
 
[20] Kanehira, T., et al., Development and experimental validation of a multidirectional circular wave basin using smoothed particle hydrodynamics. Coastal Engineering Journal, 2019. 61(1): p. 109-120.
 
[21] Zhang, Z., et al., Power fluctuation and wake characteristics of tidal stream turbine subjected to wave and current interaction. Energy, 2023. 264: p. 126185.
 
[22] Zhang, Y., et al., Quantifying the surge-induced response of a floating tidal stream turbine under wave-current flows. Energy, 2023. 283: p. 129072.
 
[23] Luznik, L., et al., The effect of surface waves on the performance characteristics of a model tidal turbine. Renewable energy, 2013. 58: p. 108-114.
 
[24] Ordonez-Sanchez, S., et al., Analysis of a horizontal-axis tidal turbine performance in the presence of regular and irregular waves using two control strategies. Energies, 2019. 12(3): p. 367.
 
[25] Ordonez Sanchez, S., et al. Effects of extreme wave-current interactions on the performance of tidal stream turbines. in 3rd Asian Wave and Tidal Energy Conference. 2016.
 
[27] Zang, W., et al., On the impact of waves and turbulence on the power fluctuations and wake structure of a tidal-stream turbine. Physics of Fluids, 2023. 35(5).
 
[28] Huang, B., et al., The effects of heave motion on the performance of a floating counter-rotating type tidal turbine under wave-current interaction. Energy Conversion and Management, 2022. 252: p. 115093.
[29] Zhang, Y., et al., The influence of waves propagating with the current on the wake of a tidal stream turbine. Applied Energy, 2021. 290: p. 116729.
 
[30] Lust, E.E., et al., The influence of surface gravity waves on marine current turbine performance. International Journal of Marine Energy, 2013. 3: p. 27-40.
 
[31] DUFOUR, M.-A., et al. Comparison of the experimental response of two horizontal axis tidal turbines to wave and current. in 25ème Congrès Français de Mécanique-CFM 2022. 2022.
 
[32] Allmark, M., et al., A phenomenological study of lab-scale tidal turbine loading under combined irregular wave and shear flow conditions. Journal of Marine Science and Engineering, 2021. 9(6): p. 593.
 
[33] Jiang, Y., et al., Structural analysis of a fibre-reinforced composite blade for a 1 MW tidal turbine rotor under degradation of seawater. Journal of ocean engineering and marine energy, 2023. 9(3): p. 477-494.
 
[34] Mullings, H., et al., Efficient prediction of tidal turbine fatigue loading using turbulent onset flow from Large Eddy Simulations. Journal of Ocean Engineering and Marine Energy, 2024. 10(3): p. 537-554.
 
[35] Van Ness, K., et al., Experimental comparison of blade pitch and speed control strategies for horizontal-axis current turbines. Journal of Ocean Engineering and Marine Energy, 2021. 7: p. 83-96.
 
[36] Zilic de Arcos, F., G. Tampier, and C.R. Vogel, Numerical analysis of blockage correction methods for tidal turbines. Journal of Ocean Engineering and Marine Energy, 2020. 6: p. 183-197.
 
[37] Apsley, D.D., T. Stallard, and P.K. Stansby, Actuator-line CFD modelling of tidal-stream turbines in arrays. Journal of Ocean Engineering and Marine Energy, 2018. 4: p. 259-271.
 
[38] Wallwork, J.G., et al., Tidal turbine array modelling using goal-oriented mesh adaptation. Journal of Ocean Engineering and Marine Energy, 2024. 10(1): p. 193-216.
 
[39] Wang, P., et al., Performance and reliability study of China's first megawatt-scale horizontal-axis tidal turbine. Applied Ocean Research, 2023. 138: p. 103648.
 
[40] Frost, C., et al., The effect of tidal flow directionality on tidal turbine performance characteristics. Renewable Energy, 2015. 78: p. 609-620.
 
[41] Farhoody, A. and R. Shafaghat, An experimental study to investigate the effect of pitch angle and wave characteristics on the performance of a horizontal axis tidal turbine. Applied Ocean Research, 2023. 138: p. 103646.
[42] Alamian, R., et al., Experimental assessment of a 100 W prototype horizontal axis tidal turbine by towing tank tests. Renewable Energy, 2020. 155: p. 172-180.
 
[43] A. Amiri, H., et al., Study of horizontal axis tidal turbine performance and investigation on the optimum fixed pitch angle using CFD: A case study of Iran. International Journal of Numerical Methods for Heat & Fluid Flow, 2020. 30(1): p. 206-227.
 
[44] Song, M., et al., Numerical and experimental investigation on the performance of three newly designed 100 kW-class tidal current turbines. International Journal of Naval Architecture and Ocean Engineering, 2012. 4(3): p. 241-255.
 
[45] Radfar, S., et al., A comprehensive insight into tidal stream energy farms in Iran. Renewable and Sustainable Energy Reviews, 2017. 79: p. 323-338.
 
[46] Rashid, A., Status and potentials of tidal in-stream energy resources in the southern coasts of Iran: A case study. Renewable and sustainable energy reviews, 2012. 16(9): p. 6668-6677.
 
[47] Zaker, N., et al., Dynamics of the Currents in the Strait of Khuran in the Persian Gulf. Journal of Shipping and Ocean Engineering, 2011. 1(2).
 
[48] Zanous, S.P., et al., Feasibility study of wave energy harvesting along the southern coast and islands of Iran. Renewable energy, 2019. 135: p. 502-514.
 
[49] Di Mascio, R. and G. Barton, The economic assessment of process control quality using a Taguchi-based method. Journal of Process Control, 2001. 11(1): p. 81-88.
 
[50] Alizadeh Kharkeshi, B., et al., Experimental & analytical hydrodynamic behavior investigation of an onshore OWC-WEC imposed to Caspian Sea wave conditions. International Journal of Maritime Technology, 2020. 14: p. 1-12.
 
[51] Zhang, J.Z., J.C. Chen, and E.D. Kirby, Surface roughness optimization in an end-milling operation using the Taguchi design method. Journal of materials processing technology, 2007. 184(1-3): p. 233-239.
 
[52] Kharkeshi, B.A., et al., Enhancing efficiency and measuring sloshing in oscillating water column (OWC) systems: An experimental investigation of novel inlet geometry optimization and innovative measurement method. Energy, 2023. 285: p. 129423.
 
[53] Zamani, M., R. Shafaghat, and B. Alizadeh Kharkeshi, Enhancing Performance Evaluation of Archimedes Screw Turbines under Optimal Conditions: A Focus on Flow Rate Analysis, Empirical Equations, and Comparative Scaling Methods. Iranica Journal of Energy & Environment, 2024. 15(2): p. 123-134.
 
[54] Khanjanpour, M.H. and A.A. Javadi, Optimization of a Horizontal Axis Tidal (HAT) turbine for powering a Reverse Osmosis (RO) desalination system using Computational Fluid Dynamics (CFD) and Taguchi method. Energy Conversion and Management, 2021. 231: p. 113833.
 
[55] Shi, W., et al., Cavitation observations and noise measurements of horizontal axis tidal turbines with biomimetic blade leading-edge designs. Ocean engineering, 2016. 121: p. 143-155.
 
[56] Chen, D., J. Jhang, and M. Guo, Application of Taguchi design method to optimize the electrical discharge machining. Journal of Achievements in Materials and Manufacturing Engineering, 2013. 57(2): p. 76-82.