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95th Percentile Power Density [W/m²]

Estimated extreme power density, outlier-tolerant and robust to cubic-velocity sensitivity

Description

95th percentile of the maximum power density (kinetic energy flux) across the water column calculated over the 1-year hindcast period, representing a robust, outlier-tolerant estimate of extreme energy flux at any depth under free-stream (undisturbed) conditions. Due to the cubic relationship between velocity and power density, extreme values are particularly sensitive to model artifacts, making the 95th percentile a more reliable metric than the absolute maximum for comparing extreme energy flux across sites. It is intended for IEC 62600-201 [@iec_62600_201] Stage 1 reconnaissance-level analysis and is intended to be input for extreme load analysis on tidal turbine components.

Equation

\[ P_{95} = \text{percentile}(95, \left[\max(P_{1,t}, ..., P_{N_{\sigma},t}) \text{ for } t=1,...,T\right]) \]

Where:

  • \(P_{i,t} = \frac{1}{2} \rho U_{i,t}^3\), power density with \(\rho = 1025\) \([\text{kg/m}^3]\)
  • \(U_{i,t} = \sqrt{u_{i,t}^2 + v_{i,t}^2}\), velocity magnitude at sigma level \(i\) at time \(t\) \([\text{m/s}]\)
  • \(N_{\sigma} = 10\), sigma layers
  • \(T\), 1 year of hindcast data

Properties

Property Value
Internal Name vap_water_column_95th_percentile_sea_water_power_density
Units W/m²