Parameters

This block contains various parameters which are used by other blocks within the project file.

The possible content of this block in not limited to physical properties of materials used in the experiment but also to values of boundary and initial conditions or source terms, physical constants, etc.

Where can the parameters be used?

The parameters defined in this block can be used in blocks:

• Media
• Process variables

Parameters vs properties

How to define a parameter?

To create a parameter within the <parameters> </parameters> tag, following template can be used:

<parameter>
    <name>...</name>
    <type>...</type>
</parameter>

Tags <name> </name> and <type> </type> are mandatory and define a human-readable name of a specific parameter and declare one of the available types with which it will be defined. Other tags depend on what is the content of <type> </type>. There are the following types available:

• Constant
• CurveScaled

Each of them will be discussed below. The same type can be used to define media properties in the media block.

Constant

This is the most basic type. It only requires the <value> </value> tag additionally where the value of the parameter is provided as a number. It will not change throughout the experiment. For example:

<parameter>
    <name>earth_acceleration</name>
    <type>Constant</type>
    <value>9.81<value>
</parameter>

For vectorial quantities, the individual entries need to be listed, e.g., <values>0.5 1 2</values>. This example will be interpreted as a 3D vector.

<parameter>
    <name>some_anisotropic_parameter</name>
    <type>Constant</type>
    <value>0.5 1 2</value>
</parameter>

CurveScaled

It requires the tags <curve> </curve> and <parameter> </parameter>. The first one contains the name of a curve defined in the <curves> </curves> block (for more detail see curves). Note that this is not the exact same type as Curve discussed in Media block.

Following variables are accessible from CurveScaled:

• spatial: x, y, z
• temporal: t

<parameter>
    <name>p_Dirichlet_right</name>
    <type>CurveScaled</type>
    <curve>p_Dirichlet_right_temporal</curve>
    <parameter>t</parameter>
</parameter>

<curve>
    <name>p_Dirichlet_right_temporal</name>
    <coords>0.0 10.0</coords>
    <values>0.0 10.0</values>
</curve>