# Actuator line NREL5MW in convectively unstable ABL with rigid blades. This benchmark problem describes the simulation of a single NREL5MW turbine using an actuator line model in a turbulent, slightly convective unstable atmospheric boundary layer. In contrast to the [flexible NREL5MW](https://exawind.github.io/exawind-benchmarks/amr-wind/actuator_line/NREL5MW_ALM_BD/README.html) turbine case, this simulation uses rigid blades with no deformation, and no turbine controller is used, so the turbine spins with fixed rotor speed and fixed blade pitch. **Contents** - [Simulation description and setup](#simulation-description-and-setup) - [Postprocessing](#postprocessing) - [Code performance](#code-performance) - [Results](#results) ## Simulation description and setup Full details provided in [**setup documentation**](setup/README.md). The characteristics of the NREL5MW turbine used in this study are are defined in the technical report [NREL/TP-500-38060](https://www.nrel.gov/docs/fy09osti/38060.pdf). The basic properties are included below | Turbine property | Value | | --- | --- | | Rotor diameter | 126 m | | Hub-height | 90 m | | Rated power | 5 MW | | Rated wind speed | 11.4 m/s | | Rated rotor speed | 12.1 rpm | | Cut in wind speed | 3 m/s | | Cut out wind speed | 25 m/s | An OpenFAST turbine model is used to calculate the blade aerodynamics. A fixed controller is used, so the blade pitch is a constant 0 degrees and rotor speed is fixed to 12.1 rpm. The NREL5MW turbine is placed in a 5km x 5km x 2km domain with a total mesh size of 70.5 million elements. The background mesh resolution is 10m, with two levels of refinement to reach 2.5m resolution at the rotor disk. For the blade-resolved problem, an additional two levels of refinement are used in the AMR-Wind domain.  This atmospheric inflow for this case is generated via the [convectively unstable](../../atmospheric_boundary_layer/convective_abl_nrel5mw/README.md) benchmark case. ## Code performance Full details provided in [**performance documentation**](performance/README.md). The job was run on an HPC cluster using 8 nodes/896 CPU's and run for 23.3 hours wall-time: | Parameter | Value | |--- |--- | | Number of nodes | 8 | | Number of CPUs | 896 | | Wall-time | 21.6 hours| | CPU-hours | 19316.9 | ## Postprocessing Full details provided in [**postprocessing documentation**](postprocessing/README.md). A full set of postprocessing scripts is provided to extract results and images from the AMR-Wind simulations. These scripts and notebooks will provide the ability to generate - velocity contour visualizations - turbine performance results - blade loading profiles - downstream wake profiles ## Results Full details provided in [**results documentation**](results/README.md). A description of the AMR-Wind results is included in the results documentation. When appropriate, these will include comparisons against results from other codes and other simulation fidelities of the same NREL5MW turbine case.