A simple 2D model of 121 QU8 elements is used in the example. It is a component on a conveyor belt used to carry coal. It has a single loadcase containing displacements, nodal stresses, gauss-point stresses, and loading data. This loading data is used to display the constraints, and the applied loads at the end of the exercise.

Figure 12.1: 10 line contours

Ten contour lines are displayed giving an overall impression of results values. Maximum and minimum values appear in the results monitor.

14 values are contoured : this would be the maximum number of contour lines that could be displayed on a 16 colour device such that each contour line would have a unique colour

PRESENT CONTOUR VALUES 0 .2E5 .5E5

Figure 12.2: Contouring by Values

Contour lines are displayed at the specified value or values.

Contours by FROM and TO :

PRESENT CONTOUR FROM 0 TO .1E6 LEVELS 9

Contour lines are displayed at both the FROM and TO values, while there are 9 intermediate contours displayed.

PRESENT CONTOUR FROM 0 TO .1E6 STEPS .2E5

Contour lines are displayed at both the FROM and TO values, while intermediate contours are displayed with the specified increment starting from the FROM value upwards.

PRESENT CONTOUR FROM .1E6 TO 0 STEPS -.2E5

Colours are reversed by reversing FROM and TO values, and giving a negative step. This is used to colour smaller values in red, as with safety factors or the highlighting of compressive stresses

Change to a display of the complete mesh

VIEW MESH

Present a simple contour display by DATUM and STEP on which to investigate advanced features of contouring, including control of colour modulation, annotation, and keylines

PRESENT CONTOUR DATUM 0 STEPS .4E5

PRESENT OPTIONS CONTOUR LINES MODULATE 3

3 colours are used in the colour modulation of the contour lines

PRESENT OPTIONS CONTOUR LINES MODULATE 5

5 colours are used in the colour modulation of the contour lines

PRESENT OPTIONS CONTOUR LINES MODULATE ALL

All available contouring colours on the current graphics device are used in the colour modulation of the contour lines

PRESENT OPTIONS CONTOUR LINES ANNOTATE 1

Every contour line segment is annotated as it is drawn; this can give a very crowded picture

PRESENT OPTIONS CONTOUR LINES ANNOTATE 2

Every second contour line segment is annotated as it is drawn element by element

PRESENT OPTIONS CONTOUR LINES ANNOTATE 10

Every tenth contour line segment is annotated as it is drawn element by element

PRESENT OPTIONS CONTOUR LINES ANNOTATE OFF

Annotation is switched off: this can be useful if many contour lines are displayed

PRESENT OPTIONS CONTOUR LINES ANNOTATE 5

The default is annotation every fifth contour line segment

PRESENT OPTIONS CONTOUR LINES KEYLINE 2

Figure 12.3 Keyline set to 2

Every second contour line is a keyline and is annotated : lines in between are not annotated

PRESENT OPTIONS CONTOUR LINES KEYLINE 4

Every fourth contour line is a keyline and is annotated : lines in between are not annotated

PRESENT OPTIONS CONTOUR LINES KEYLINE 1

The default is that every line is a keyline and is annotated every fifth contour line segment

PRESENT OPTIONS CONTOUR FILL

Solid colour can be used on graphical displays that are capable of area fill

PRESENT OPTIONS CONTOUR FILL MAX

It is possible to fill each element in a colour representative of the highest result value occurring within the element

PRESENT OPTIONS CONTOUR FILL MIN

It is possible to fill each element in a colour representative of the lowest result value occurring within the element

PRESENT OPTIONS CONTOUR FILL ALL

The default for contour fill is that all results will be used to contour each element face

PRESENT OPTIONS CONTOUR EDGES

The mesh can be displayed using colour modulation so that each edge is coloured so that it is representative of the result values along that edge

PRESENT OPTIONS CONTOUR EDGES MAX

Colours are modulated so that each edge is coloured so that it is representative of the highest result value within that edge

PRESENT OPTIONS CONTOUR EDGES MIN

Colours are modulated so that each edge is coloured so that it is representative of the lowest result value within that edge

PRESENT OPTIONS CONTOUR EDGES ALL

The default is that the full range of result values within the edge will be used for colour modulation along the edge

Select contour lines and an outline view

PRESENT OPTIONS CONTOUR LINES

VIEW EDGES

Turn off all contour annotation

PRESENT OPTIONS CONTOUR LINES ANNOTATE OFF

Select 30 levels of contour

PRESENT CONTOUR LEVELS 30

This results presentation mode can be used to give a feeling of the flow of the stress and the rate of change of stresses within the model

PRESENT CONTOUR LEVELS 60

The closeness of the contour lines gives an indication of stress gradient

PRESENT CONTOUR LEVELS 100

The maximum number of line contours allowed are 100 levels : which are possibly too many levels for this model

PRESENT OPTIONS CONTOUR FILL

Figure 12.4: Contour fill plot

If there are not sufficient colours to permit a requested operation, the colours will be mapped, and a warning will be issued

PRESENT CONTOUR LEVELS 13

With contour fill, one more colour than the number of colours specified will be required to colour code the picture

So far in this tutorial, only nodal values have been used for contouring. Elementwise nodal values or gauss-point values may also be used

UTILITY TABULATE LOADCASES

RESULTS GAUSSIAN G SXX

PRESENT CONTOUR LEVELS 13

If elementwise values, or gauss-point values are used there will typically be discontinuities at the element boundaries

DRAWING CONTENTS TEXT POSITION

results discontinuities here

DRAWING CONTENTS POINTER POSITION

Text and pointers can be added to the picture to draw attention to points of interest

EYE ZOOM IN .5 .424 .684 .619

Discontinuities can indicate where the mesh needs to be refined further. Averaged nodal values will smooth out these discontinuities.

DRAWING CONTENTS TEXT DELETE ALL;

DRAWING CONTENTS POINTER DELETE ALL;

PRESENT OPTIONS CONTOUR FILL MAX

In this display the highest gauss-point result within the element determines the colour used for contouring.

PRESENT OPTIONS CONTOUR FILL ALL;

RESULTS CALCULATE VONMISES

PRESENT CONTOUR LEVEL 13

A display of von mises equivalent stress calculated from the gauss-point values using contour fill

RESULTS CALCULATE P-STRESS P1 2DSORT

PRESENT CONTOUR LEVELS 12

Repeat with principal stress P1 and twelve levels of contour

RESULTS CALCULATE P-STRESS P2 2DSORT

PRESENT CONTOUR LEVELS 12

Repeat with principal stress P2 and twelve levels of contour

The display of constraints superimposed on the deformed mesh

VIEW OPTIONS DEFORM ALL

LABEL MESH CONSTRNTS

The display of the applied loading using 3D vectors

RESULTS NODAL END ALL

PRESENT OPTIONS VECTORS 3D-HEADS

PRESENT VECTORS

A dotted outline representation is useful to superimpose the undeformed mesh on the picture

EYE LOCATE

Figure 12.5: Loads and Constraints