Wind speed correction under thrust similarity for an 18-MW FOWT: A wind-tunnel study

The global energy transition has positioned offshore wind power as a strategic priority in deep-water renewable energy development, with floating offshore wind turbines (FOWT) emerging as pivotal technological solutions. Traditional Froude scaling cannot ensure dynamic similitude of aerodynamic forces in wave-basin experiments. To reconcile this mismatch, a wind speed correction coefficient K is introduced and evaluated under an equal thrust criterion. Wind-tunnel tests on an 18MW turbine are conducted to build a quadratic surrogate of thrust as a function of wind speed and pitch, from which K is quantified across operating conditions. The results show a clear two-regime behavior: at low wind speeds, a ReynoldsPenalty Regime requires large wind-speed corrections, whereas at higher speeds a Correction Convergent Regime emerges in which the required correction shrinks as the discrepancy from the Froude-scaled progressively disappears. After applying K, the model's thrust matches the target thrust, confirming restored thrust similarity. This approach improves aerodynamic load fidelity in FOWT tests and provides more accurate wind input parameters for integrated multi-physics modeling and design optimization.