Flexcom > Data Inputs > $LOAD CASE

Purpose

To specify Stokes V regular wave loading.

Theory

Refer to Stokes V Wave for further information on this feature.

Keyword Format

Blocks of lines which define the wave loading parameters.

Block defining a regular Stokes wave:

[OPTION=SUPERPOSE]

Height, Wave Period [, Direction] [, Equivalent Airy Wave Amplitude] [, Equivalent Airy Wave Period]

A non-zero Equivalent Airy Wave Period with no Equivalent Airy Wave Amplitude (or an amplitude of 0) is invalid.

Table Input

Stokes – 5th Order

Input:	Description
Wave Height:	The Stokes V wave height (crest to trough).
Wave Period:	The Stokes V wave period.
Direction:	The wave direction, measured anti-clockwise from the global-Y direction. All waves in Flexcom emanate from the origin. The default direction is 0°.

Stokes – Equivalent Airy

Input:	Description
Wave Height:	The Stokes V wave height (crest to trough).
Wave Period:	The Stokes V wave period.
Direction:	The wave direction, measured anti-clockwise from the global-Y direction. All waves in Flexcom emanate from the origin. The default direction is 0°.
Equivalent Airy Wave Amplitude:	The amplitude of the Airy wave used to determine vessel response to the Stokes V wave.
Equivalent Airy Wave Period:	The period of the Airy wave used to determine vessel response to the Stokes V wave. The default is the Stokes V wave period.

Stokes – Superposition of Harmonics

Input:	Description
Wave Height:	The Stokes V wave height (crest to trough).
Wave Period:	The Stokes V wave period.
Direction:	The wave direction, measured anti-clockwise from the global-Y direction. All waves in Flexcom emanate from the origin. The default direction is 0°.

Notes

(a)If your analysis includes vessel response to a Stokes V wave:

•Using the Fifth Order option means that the order of the response will be 5th order.

•Using the Equivalent Airy Wave option means that the response will be first order (sinusoidal).

•Using the Superposition of Harmonics option means that that response will be calculated as a superposition of 5 individual components.

(b)You can specify an equivalent Airy wave amplitude without inputting a corresponding period, in which case the Stokes V wave period is used by default. Specification of an Airy wave period without a corresponding wave amplitude is invalid. Of course if an analysis does not include vessel response to waves, equivalent Airy wave parameters are immaterial and unused.