FLORIS v4

[misi9170]

FLORIS v4.0

FLORIS v4 brings significant additional flexibility to FLORIS while streamlining the underlying solving code.

Major updates, along with associated pull requests, are listed below.

API rework

Main user class

In an acknowledgement that for most users, the FlorisInterface is, for all intents and purposes,
FLORIS itself, we have renamed this class FlorisModel, and nominally instantiate it as fmodel.
The uncertainty interface and parallel interface have been renamed for consistency.

• Add utilities for floris models by @paulf81 in Add utilities for floris models #840
• Update uncertainty interface to 4d, new API by @paulf81 in Update uncertainty interface to 4d, new API #821

set() run() paradigm

Switches from steps reinitialize(), calculate_wake() to the simpler set(), run() pair.
Control setpoints are now also entered through set(), and remembered on the fmodel object, and
run() takes no arguments but must be called prior to querying for any power outputs.

• Move FlorisInterface .reinitialize() / .calculate_wake() to .set() / .run() by @rafmudaf in Move FlorisInterface .reinitialize() / .calculate_wake() to .set() / .run() #823

Wind data objects

set() is now strict about requiring equal lengths for all arguments. To facilitate simpler provision of wind data
to the FlorisModel, we have built "wind data" objects (TimeSeries, WindRose, WindTIRose) to handle broadcasting, storing frequencies of occurrence, etc.

• Adds classes to structure wind energy data for FLORIS by @paulf81 in Adds classes to structure wind energy data for FLORIS #775
• Add CSV reader for WindRose by @paulf81 in Add CSV reader for WindRose #848
• Save WindData onto FlorisModel and simplify post-run() calls by @misi9170 in Save WindData onto FlorisModel and simplify post-run() calls #849
• Drive layout optimizations using WindData objects by @paulf81 in Drive layout optimizations using WindData objects #822

Market value

As well as computing annual energy production, FLORIS now facilitates the use of computing the annual value of
energy when value is stored on the wind data objects. This may also be used for layout optimization.

• Enabling layout optimization for value by @ejsimley in Enabling layout optimization for value #862

Turbines

Turbine modeling

The underlying code for modeling turbine operation has been significantly updated, and turbines are now specified
in terms of their thrust coefficient and absolute power (specified in kW).

• Replace Cp with power in turbine definition and throughout FLORIS by @misi9170 in Replace Cp with power in turbine definition and throughout FLORIS #765
• Update reference wind turbines in the default turbine library by @misi9170 in Update reference wind turbines in the default turbine library #771

Turbine operation

Additionally, the operation of turbine has been made more flexible to allow various types of operation (e.g. wake steering, derating, active wake mixing).

• Update to more flexible turbine operation model definitions by @misi9170 in Update to more flexible turbine operation model definitions #770
• Clarify turbine definition terms by @misi9170 in Clarify turbine definition terms #815
• Remove small variations in above rated power by @paulf81 in Remove small variations in above rated power #784

Active wake mixing with Helix

Utilizing new turbine operation models, the Helix wake mixing strategy has a preliminary implementation that models both effects on turbine power and thrust coefficient and effects on wake recovery.

• Added helix model and examples by @jfrederik-nrel in Added helix model and examples #842

Derating and shut off

The ability to derate turbines by providing a derating limit, as well as the ability to shut off turbine entirely,
has been added using new turbine operation models.

• Add de-rating op model by @paulf81 in Add de-rating op model #783
• Add support to shut off turbines by @paulf81 in Add support to shut off turbines #799

Multidimensional turbines

Support for multidimensional turbine power/thrust curves has been broadened and is now available in all wake models.

• Update multidim turbine files to use absolute turbine power by @bayc in Update multidim turbine files to use absolute turbine power #818
• Support multidimensional turbine definitions in all wake models by @misi9170 in Support multidimensional turbine definitions in all wake models #812

Code base and structural changes

4-dimensional underlying arrays

To streamline operation of the underlying solving code, data structures have been reduced to 2 or 4
dimensions: n_findex x n_turbines x (n_grid_1 x n_grid_2).
The "findex" dimension now holds all "conditions" for FLORIS to solve, and collapses the separated
n_wind_directions x n_wind_speeds found in FLORIS v3 into a single dimension.

• Convert core data structures and tools to use 4D arrays by @rafmudaf in Convert core data structures and tools to use 4D arrays #764
• Update yaw and layout optimization tools for 4D by @bayc in Update yaw and layout optimization tools for 4D #790
• Convert turbulence intensity from single value to n_findex length array by @paulf81 in Convert turbulence intensity from single value to n_findex length array #782

Rework of package structures

To clear up confusing naming, much of the user interface tools have been moved up to the base floris package,
while the solve code is now in the floris.core package.

• Rename floris.simulation, floris.tools to floris.core, floris by @rafmudaf in Rename floris.simulation, floris.tools to floris.core, floris #830

Miscellaneous improvements

Various improvements of note have been made across the repository, including improvements to documentation and reorganizing the examples.

• Change from Apache to BSD 3-clause license by @paulf81 in Change from Apache to BSD 3-clause license #810
• Collect all layout visualization tools in FLORIS by @paulf81 in Collect all layout visualization tools in FLORIS #805
• Refactor examples by @paulf81 in Refactor examples #843
• Build out v4 documentation by @misi9170 in Build out v4 documentation #860

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Full Changelog: v3.6...v4.0

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Developer checklist

Release checklist:

• Update the version in
  • README.md
  • floris/VERSION
• Verify docs builds correctly
• Create a tag in the NREL/FLORIS repository