Expression Settings

Expressions may be in the form of a simple pml expression or alternatively a pml function. In all cases, except temperatures and pressures, there may be multiple expressions which are tested in sequence until a non zero result is obtained.

Expressions are evaluated after navigating to the component for which data is required, so the variable !!ce may be used freely in expressions.

Functions are pml2 functions defined with a fixed set of parameters. For example wall thickness is defined as a function which gets the current tube wall thickness or alternatively the wall thickness from the current component. When a function is called, it is called from an object called a stressgroup which has a member !this.node which represents the ppoint for which information is being gathered. The member !this.node is a stressnode object which has members:

• .bore

• .Component

• .ComponentType

• .Connection

• .ConnectionType

• .Position

• .wallthickness

• .point

• .OutsideDiameter

• .insulationmat

• .insulationthickn

• .material

• .weight

• .ltubelength

• .bendradius

• .AlphaAngle

• .temperature

• .pressure

• .sif

• .restlines

• .caselist

• .modified

• .restraint

• .Type

• .Stiffness

• .Gap

• .Friction

• .load

• .deflection

• .rotation

• .status

• .bendtype

All of these may be used by the user function provided they are passed to it as shown below:

!!psifindwall(!this.node.component,!this.node.point)

Here the parameters are a dbref and current ppoint.

Note:
!this.node.component could have been replaced by !!ce as the system would be at that component at the time it was run.