# Concept of I/O (input/output) parameter

## Introduction

In order to carry out a parametric analysis, it is necessary to define what the study variable quantities are: air gap size, material magnetic properties, etc.

In order to carry out a time dependent study (transient application), it is necessary to define what the study quantities are variable in function of time: instantaneous value of current in the coil, etc.

The definition of the variable quantities is carried out in Flux by means of the I/O (input/output) parameter.

## Concept of I/O (input/output) parameter

An I/O (input/output) parameter is a variable quantity of the study, whose variations are defined:

• by means of discrete values (the I/O parameter is then called controllable*)
• by another I/O parameter defined by means of a table of values
• by means of other I/O parameters defined by formulas
Note: * A controllable I/O parameter is a parameter, which is capable to control a solving process. (see § Concept of scenario and solving process control).

## Examples

The corresponding I/O (input/output) parameters given in the previous example (see § Parametric analysis: examples) are presented in the tables below.

Parametric analysis I/O parameter Examples of values
Name Type
(1) geometric airgap controlled 0.7, 0.9, 1.1 and 1.3 mm
(2) physical mur controlled 100, 1000 and 4000
Time dependent study I/O parameter Examples of values
Name Type
(3) time dependent study (transient application) time controlled 0, 0.005, 0.010, 0.015, … s
current formula

current = 25 * Valid(time,0.02)

Time dependent study I/O parameter Examples of values
Name Type
(3) time dependent study (transient application) time controlled 0, 0.005, 0.010, 0.015, … s
current tabuled time current
0 0
0.019 0
0.02 25
0.04 25