4.18.1. Nomenclature
ABLSolver |
atmospheric boundary layer solver |
AWAE |
ambient wind and array effects (module) |
\(a(r)\) |
axial induction factor, distributed radially |
\(a_K\) |
coherence decrement parameter |
BEM |
blade-element momentum |
\(b_K\) |
coherence offset parameter |
\(C^\text{O}_\text{HWkDfl}\), \(C^\text{OY}_\text{HWkDfl}\), \(C^\text{x}_\text{HWkDfl}\), and \(C^\text{xY}_\text{HWkDfl}\) |
calibrated parameters in the horizontal wake-deflection correction |
\(c_\text{max}\) |
maximum blade chord length |
\(C_\text{Meander}\) |
calibrated parameter for wake meandering |
\(C_\text{NearWake}\) |
calibrated parameter in the near-wake correction |
\(C_\text{WakeDiam}\) |
calibrated parameter in the wake-diameter calculation |
\(C^\text{DMax}_{\nu \text{Amb}}\), \(C^\text{DMin}_{\nu \text{Amb}}\), \(C^\text{Exp}_{\nu Amb}\), and \(C^\text{FMin}_{\nu Amb}\) |
calibrated parameters in the eddy-viscosity filter function for ambient turbulence |
\(C^\text{DMax}_{\nu \text{Shr}}\), \(C^\text{DMin}_{\nu \text{Shr}}\), \(C^\text{Exp}_{\nu \text{Shr}}\), and \(C^\text{FMin}_{\nu \text{Shr}}\) |
calibrated parameters in the eddy-viscosity filter function for the wake shear layer |
\(^\text{AzimAvg}C_t(r)\) and \(^\text{FiltAzimAvg}C_t(r)\) |
azimuthally averaged thrust-force coefficient (normal to a rotor disk), distributed radially, and its low-pass time-filtered value |
\(Coh_{i,j}\) |
magnitude of partial coherence between points \(i\) and \(j\) |
DLL |
dynamic-link library |
DWM |
dynamic wake meandering |
\(D_\text{Grid}\) |
Assumed rotor diameter when generating TurbSim inflow |
\(D^\text{Rotor}\) and \(^\text{Filt}D_{n_p}^\text{Rotor}\) |
rotor diameter and its low-pass time-filtered value at wake plane \(n_p\) |
\(D_{n_p}^\text{Wake}\) |
wake diameter at wake plane \(n_p\) |
FLORIS |
FLOw Redirection and Induction in Steady state |
\(f\) |
frequency |
\(f_c\) |
cutoff (corner) frequency of the low-pass time filter |
\(\vec{f}_{n_b}(r)\) |
aerodynamic applied loads distributed radially per unit length for blade \(n_b\) |
\(f_\text{max}\) |
maximum excitation frequency |
\(F_{\nu \text{Amb}}(x)\) |
eddy-viscosity filter function associated with ambient turbulence |
\(F_{\nu \text{Shr}}(x)\) |
eddy-viscosity filter function associated with the wake shear layer |
HFM |
high-fidelity modeling |
HPC |
high-performance computer |
\(I\) |
three-by-three identify matrix |
\(K\) |
velocity components \(u\), \(v\), and \(w\) |
\(k_{\nu \text{Amb}}\) |
calibrated parameter for the influence of ambient turbulence in the eddy viscosity |
\(k_{\nu \text{Shr}}\) |
calibrated parameter for the influence of the wake shear layer in the eddy viscosity |
LES |
large-eddy simulation |
MFoR |
moving frame of reference |
MPI |
message-passing interface |
NaN |
not a number |
NREL |
National Renewable Energy Laboratory |
\(N\) and \(n\) |
number of discrete-time steps and discrete-time-step counter |
\(N_b\) and \(n_b\) |
number of rotor blades and blade counter |
\(N_{n_p}^\text{Polar}\) and \(n^\text{Polar}\) |
number of points in the polar grid of wake plane \(n_p\) and point counter |
\(N^\text{Wake}\) and \(n^\text{Wake}\) |
number of wakes overlapping a given wind data point in the wind domain and wake counter |
\(N_P\) and \(n_P\) |
number of wake planes and wake-plane counter |
\(N_r\) and \(n_r\) |
number of radial nodes and radii counter |
\(N_t\) and \(n_t\) |
number of wind turbines and turbine counter |
OF |
OpenFAST (module) |
OpenMP |
open multiprocessing |
\(\vec{p}^\text{Hub}\) |
global position of a rotor center |
\(\vec{p}^\text{Plane}_{n_p}\) |
global position of the center of wake plane \(n_p\) |
RAM |
random-access memory |
RSS |
root-sum-squared |
\(r\) and \(r^\text{Plane}\) |
radius in the axisymmetric coordinate system |
\(\hat{r}^\text{Plane}\) |
radial unit vector in the axisymmetric coordinate system |
\(S\) |
global \(X\)-, \(Y\)-, and \(Z\)-coordinate |
SC |
super controller (module) |
SOWFA |
Simulator fOr Wind Farm Applications |
\(t\) |
simulation time |
\(TI_\text{Amb}\) and \(^\text{Filt}TI_{\text{Amb}_{n_p}}\) |
ambient turbulence intensity of the wind at a rotor and its low-pass time-filtered value for wake plane \(n_p\) |
\(u^d\) |
discrete-time inputs |
\(V_\text{Advect}\) |
advection speed of the synthetic wind data |
\(\vec{V}_\text{Amb}^\text{High}\) |
ambient wind across a high-resolution wind domain around a turbine |
\(\vec{V}_\text{Amb}^\text{Low}\) |
ambient wind across a low-resolution wind domain throughout the wind farm |
\(\vec{V}_\text{Dist}^\text{High}\) |
disturbed wind across a high-resolution wind domain around a turbine |
\(\vec{V}_\text{Dist}^\text{Low}\) |
disturbed wind across a low-resolution wind domain throughout the wind farm |
\(V_\text{Hub}\) |
mean hub-height wind speed |
\(\vec{V}_{n_p}^\text{Plane}\) and \(^\text{Filt}\vec{V}_{n_p}^\text{Plane}\) |
advection, deflection, and meandering velocity and its low-pass time-filtered value of wake plane \(n_p\) |
\(V_r\) |
radial velocity in the axisymmetric coordinate system |
\(V_{r_{n_p}}^\text{Wake}(r)\) |
radial wake-velocity deficit at wake plane \(n_p\), distributed radially |
VTK |
Visualization Toolkit |
\(^\text{DiskAvg}V_x^\text{Rel}\) and \(^\text{FiltDiskAvg}V_x^\text{Rel}\) |
rotor-disk-averaged relative wind speed (ambient plus wakes of neighboring turbines plus turbine motion), normal to the disk, and its low-pass time-filtered value |
\(V_x\) |
axial velocity in the axisymmetric coordinate system |
\(V_{x_{n_p}}^\text{Wake}(r)\) |
axial wake-velocity deficit at wake plane \(n_p\), distributed radially |
\(^\text{DiskAvg}V_x^\text{Wind}\) and \(^\text{FiltDiskAvg}V_{x_{n_p}}^\text{Wind}\) |
rotor-disk-averaged ambient wind speed, normal to the disk, and its low-pass time-filtered value at wake plane \(n_p\) |
\(w_{n^\text{Wind}}\) |
weighting in the spatial averaging for wind data point \(n^\text{Wind}\) |
WD |
wake dynamics (module) |
WISDEM |
Wind-Plant Integrated System Design & Engineering Model |
\(x\) and \(x_{n_p}^\text{Plane}\) |
downwind distance from a rotor to wake plane \(n_p\) in the axisymmetric coordinate system |
\(X\), \(Y\), and \(Z\) |
inertial-frame coordinates, with Z directed vertically upward, opposite gravity, X directed horizontally nominally downwind (along the zero-degree wind direction), and Y directed horizontally transversely |
\(\hat{X}\), \(\hat{Y}\), and \(\hat{Z}\) |
unit vectors of the inertial-frame coordinate system, parallel to the X, Y, and X coordinates |
\(x^d\) |
discrete-time states |
\(X^d(\quad)\) |
discrete-time state functions |
\(\hat{x}^\text{Disk}\) |
orientation of a rotor centerline |
\(\hat{x}_{n_p}^\text{Plane}\) |
orientation of wake plane \(n_p\) |
\(y^d\) |
discrete-time outputs |
\(Y^d(\quad)\) |
discrete-time output functions |
\(z_\text{bot}\) |
bottom vertical location of synthetic turbulence inflow grid |
\(\alpha\) |
low-pass time-filter parameter |
\(\Delta t\) |
discrete time step (increment) |
\(\gamma^\text{YawErr}\) and \(^\text{Filt}\gamma_{n_p}^\text{YawErr}\) |
nacelle-yaw error of a rotor and its low-pass time-filtered value at wake plane \(n_p\) |
\(\nu_T\) |
eddy viscosity |
\(\rho\) |
air density |
2D |
two dimensional |
3D |
three dimensional |