Horizontal Wind Model 14

Implement Horizontal Wind Model 14

• Library:

• Aerospace Blockset / Environment / Wind

• 

Description

The Horizontal Wind Model 14 block implements the U.S. Naval Research Laboratory (HWM™) routine to calculate the meridional and zonal components of the wind for a set of geographic coordinates: latitude, longitude, and altitude.

Limitation

For code generation, use this block only for targets whose type is int 32 or higher.

Ports

Input

First — geodetic latitude (μ), longitude (l), and geopotential altitude (h)

three-element vector of doubles

The input specifies the geodetic latitude (μ), longitude (l), and geopotential altitude (h) where the block implements the model.

Latitude and longitude values are in degrees.

The altitude value is in the units you selected in the Units parameter. Specify the altitude element as a value between 0 and 500 km. Values are held outside the range 0 to 500 km.

Second — day of year

scalar double

The input specifies the day of year in Coordinated Universal Time (UTC). The input specifies the day as a value between 1 and 366 (for a leap year). Values are wrapped within 1 to 366 days.

Third — elapsed seconds

scalar double

Contains elapsed seconds since midnight for the selected day, in UTC.

Fourth (Optional) — Ap index

scalar double

Contains the Ap index for the Universal Time (UT) when the block evaluates the model. Select the index from the NOAA National Geophysical Data Center, which contains 3 hour interval geomagnetic disturbance index values. If the Ap index value is greater than zero, the software takes into account magnetic effects during model evaluation.

Output

First — wind velocity vector

1-by-2 vector of doubles

The wind velocity vector contains the meridional and zonal wind components in that order.

Parameters

Units — input and output units

Metric (MKS) (default) | English (Velocity in ft/s) | English (Velocity in kts)

Input and output units for wind speed and velocity, specified as:

Units	Wind Speed	Wind Velocity
Metric (MKS)	Meters per second	Meters per second
English (Velocity in ft/s)	Feet per second	Feet per second
English (Velocity in kts)	Knots	Knots

Programmatic Use

Block Parameter: units

Type: character vector

Values: 'Metric (MKS)' | 'English (Velocity in ft/s)' | 'English (Velocity in kts)'

Default: 'Metric (MKS)'

Model — horizontal wind model

Quiet (default) | Total | Disturbance

Select the horizontal wind model type for which to calculate the wind components.

• Quiet

  Calculate the horizontal wind model without the magnetic disturbances. For this model type, do not input an Ap index value.

• Total

  Calculate the combined effect of the quiet and magnetic disturbances. For this model type, input Ap index values greater than or equal to zero.

• Disturbance

  Calculate the effect of magnetic disturbances in the wind. For this model type, input Ap index values greater than or equal to zero.

Programmatic Use

Block Parameter: model

Type: character vector

Values: 'Quiet' | 'Total' | 'Disturbance'

Default: 'Quiet'

Action for out-of-range input — block behavior

Error (default) | Warning | None

Specify the block behavior when the block inputs are out of range.

Value	Description
Error (default)	MATLAB® returns an exception, and model simulation stops. For Accelerator and Rapid Accelerator modes, setting the action to Error has no effect and the model behaves as though the action is set to None.
Warning	Warning in the Diagnostic Viewer, and model simulation continues. For Accelerator and Rapid Accelerator modes, setting the action to Warning has no effect and the model behaves as though the action is set to None.
None	No action. The block imposes upper and lower limits on an input signal.

Programmatic Use

Block Parameter: action

Type: character vector

Values: 'None' | 'Warning' | 'Error'

Default: 'Error'

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2016b

R2021b: Horizontal Wind Model 14 Block Possible Changed Returned Values

The Horizontal Wind Model 14 block now accepts:

• day port values that are decimal, negative, 0, or greater than 366.

• sec port values that are 0 or greater than 86400.

As a result, the output values from this block might change from previous releases.