floris 0.0.0

A wind turbine wake modeling software

For questions regarding FLORIS, please contact Jen Annoni, Paul Fleming, or Rafael Mudafort.

Background and objectives

This FLORIS model is designed to provide a computationally inexpensive, controls-oriented model of the steady-state wake characteristics in a wind farm. This can be used for real-time optimization and control. This version of FLORIS implements a 3D version of the Jensen, original FLORIS (Gebraad et. al. 2016), and Gaussian wake model. Literature on the Gaussian model can be found in the following papers:

1. Niayifar, A. and Porté-Agel, F.: A new 15 analytical model for wind farm power prediction, in: Journal of Physics: Conference Series, vol. 625, p. 012039, IOP Publishing, 2015.

2. Dilip, D. and Porté-Agel, F.: Wind Turbine Wake Mitigation through Blade Pitch Offset, Energies, 10, 757, 2017.

3. Abkar, M. and Porté-Agel, F.: Influence of atmospheric stability on wind-turbine wakes: A large-eddy simulation study, Physics of Fluids, 27, 035 104, 2015.

4. Bastankhah, M. and Porté-Agel, F.: A new analytical model for wind-turbine wakes, Renewable Energy, 70, 116–123, 2014.

5. Bastankhah, M. and Porté-Agel, 5 F.: Experimental and theoretical study of wind turbine wakes in yawed conditions, Journal of FluidMechanics, 806, 506–541, 2016.

Architecture

An architecture diagram as in input to draw.io is contained in the repository at FLORIS/florisarch.xml.

Generally, a user will not have to write Python code in order to express a wind farm, turbine, or wake model combination. Currently, an example wake model, turbine, and wind farm is expressed in examples/example_input.json.

Dependencies

The following packages are required for FLORIS

• Python3

• NumPy v1.12.1

• SciPy v0.19.1

• matplotlib v2.1.0

• pytest v3.3.1

After installing Python3, the remaining dependencies can be installed with pip referencing the requirements list using this command:

pip install -r requirements.txt

Installation

Using pip, FLORIS can be installed in two ways

• local editable install

• using a tagged release version from the pip repo

For consistency between all developers, it is recommended to use Python virtual environments; this link provides a great introduction. Using virtual environments in a Jupyter Notebook is described here.

Local editable installation

The local editable installation allows developers maintain an importable instance of FLORIS while continuing to extend it. The alternative is to constantly update python paths within the package to match the local environment.

Before doing the local install, the source code repository must be cloned directly from GitHub:

git clone https://github.com/wisdem/floris

Then, using the local editable installation is as simple as running the following command from the parent directory of the cloned repository:

pip install -e FLORIS/

Finally, test the installation by starting a python terminal and importing FLORIS:

import floris

pip repo installation

The Floris version available through the pip repository is always the latest tagged and released version. This version represents the most recent stable, tested, and validated code.

In this case, there is no need to download the source code directly. FLORIS and its dependencies can be installed with:

pip install floris

Executing FLORIS

floris is an importable package and should be driven by a custom script. We have provided an example driver script at example/example_script.py and a Jupyter notebook detailing a real world use case at example/FLORIS_Run_Notebook.ipynb.

Generally, a Floris class should be instantiated with a path to an input file as the sole argument:

Floris("path/to/example_input.json")

Then, driver programs can calculate the flow field, produce flow field plots, and incorporate the wake estimation into an optimization routine or other functionality.

Testing

In order to maintain a level of confidence in the software, FLORIS is expected to maintain a reasonable level of test coverage. To that end, there are unit, integration, and regression tests included in the package.

Unit tests are currently included in FLORIS and integrated with the pytest framework.

See the testing documentation at tests/README.rst for more information.

Future work

Coming soon

License

Copyright 2017 NREL

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.