Engee documentation

Aerodynamic Forces and Moments

Calculation of aerodynamic force and moment.

aerodynamic forces and moments

Description

Block Aerodynamic Forces and Moments calculates the components of aerodynamic force and aerodynamic moment relative to the aircraft centre of gravity in the linked coordinate system using the following formulas.

Aerodynamic force components:

where

  • - is the longitudinal force coefficient;

  • - normal force coefficient;

  • - shear force coefficient;

  • - velocity head;

  • - characteristic area.

Components of aerodynamic moment:

where

  • - is the roll moment coefficient;

  • - yaw moment coefficient;

  • - pitching moment coefficient;

  • - characteristic linear dimension of the aircraft;

  • - average aerodynamic chord of the wing;

  • , , - coordinates of the centre of gravity;

  • , , - coordinates of the centre of pressure.

Ports

Input

# Coefbody — aerodynamic coefficients
`vector 6 to 1

Details

Coefficients of aerodynamic force and moment components along the axes in a coupled coordinate system, given as a vector. Elements of the vector:

  1. - longitudinal force coefficient.

  2. - normal force coefficient.

  3. - transverse force coefficient.

  4. - roll moment coefficient.

  5. - yaw moment coefficient.

  6. - pitching moment coefficient.

Data types

Float64.

Complex numbers support

No

# qbar — velocity heads
`vector 3 to 1

Details

Velocity heads calculated from the components of aircraft velocity along the axes of a coupled coordinate system, given as a vector.

Data types

Float64.

Complex numbers support

No

# CG — centre of gravity coordinates
`vector 3 to 1

Details

The coordinates of the centre of gravity of an aircraft. Measured in units of length, given as a vector.

Data types

Float64.

Complex numbers support

No

# CP — centre of pressure coordinates
`vector 3 to 1

Details

The coordinates of the centre of pressure of an aircraft, given as a vector. Measured in units of length.

Data types

Float64.

Complex numbers support

No

Output

# Fbody — aerodynamic forces
`vector 3 to 1

Details

The components of the aerodynamic force relative to the centre of mass of an aircraft in a coupled coordinate system, given as a vector. Elements of the vector:

  1. - longitudinal force.

  2. - normal force.

  3. - transverse force.

Measured in units of force.

Data types

Float64.

Complex numbers support

No

# Mbody — aerodynamic moments
`vector 3 to 1

Details

The components of the aerodynamic moment relative to the centre of mass of an aircraft in a coupled coordinate system, given as a vector. Elements of the vector:

  1. - roll moment.

  2. - yaw moment.

  3. - pitching moment.

Measured in units of moment.

Data types

Float64.

Complex numbers support

No

Parameters

Parameters

# Reference area — characteristic area

Details

The characteristic area of an aircraft. It is measured in units of area. For aircraft, the wing area is usually taken as the characteristic area.

Default value

1.0

Program usage name

S

Tunable

No

Evaluatable

Yes

# Reference span — mean aerodynamic chord of the wing

Details

The average aerodynamic chord of a wing. Measured in units of length.

Default value

1.0

Program usage name

b

Tunable

No

Evaluatable

Yes

# Reference length — characteristic linear dimension

Details

The characteristic linear dimension of an aircraft. It is measured in units of length. For aircraft, the characteristic linear dimension is usually taken as the wingspan.

Default value

1.0

Program usage name

cbar

Tunable

No

Evaluatable

Yes

Additional options

C code generation: Yes