calculate external_work command

Purpose

This command calculates the external work of a mesh (examples).

Syntax

calculate external_work keyword/value pairs

Keywords

Description

mesh

mandatory keyword, ID of a mesh command

mode

available options: all or torque_only or force_only
default: all

id

user-assigned name for the command call

particle_group

ID of the group of particles on which the command is applied
default: all

Examples

calculate external_work mesh dredge
calculate external_work mesh mixer mode torque_only id mixerTorque
calculate external_work mesh dredge mode force_only particle_group rocks

Description

This command calculates the external work that is performed my a mesh. The external work is defined as the time integral of the scalar product of force with velocity plus the scalar product of torque times angular velocity.

In case the keyword mode is defined with a value other than all only the selected component is integrated, i.e. for force_only and torque_only only the force or the torque is used in the integration, respectively.

If the torque of the mesh shall be taken into account it is mandatory to set the reference_point_torque in the mesh command.

Output information

This command calculates a global scalar which contains the value of the external work, the force or the torque (depending on the mode). This value can be used by any command that uses a global scalar value as input. See Section_howto 15 for an overview of Aspherix® output options.

When using the output_settings command the global scalar of the command is automatically written to the simulation_data.csv / result_monitor.csv file.

Alternatively, also the write_to_file command can be used to output the data to a specified file.

Example for saving the result to a separate file

calculate external_work mesh mes1 id external
calculate external_work mesh mes1 mode force_only id external_force
calculate external_work mesh mes1 mode torque_only id external_torque
write_to_file file ext.txt string "id_time id_external id_external_force id_external_torque" &
   string "time work force torque"