Engineering Solutions

Temperatures panel

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Temperatures panel
Temperatures panel

Use the Temperatures panel to create temperature constraints. This is accomplished by applying a load that represents temperatures to nodes, components surfaces, sets, points, or lines.

Temperatures are load config 5 and are displayed as a vertical line with the letter T at the top.

By default, temperatures are displayed relative to the model size. You can change this size by entering a different value in the relative size field. You can also use the uniform size option to have all loads displayed as the same size.

Finally, you can remove the on-screen text labels of all temperatures by deactivating the label loads checkbox.

Subpanels and Inputs

The Temperatures panel contains the following subpanels and command buttons:

Panel Inputs

Input

Action

entity selector

Use the switch to choose the entities to apply the temperature to: nodes, comps, surfs, sets, points, or lines.

In any case, the forces are applied to nodes; this selection simply determines how those nodes are selected. Geometric points select the nodes at which they exist. Comps select all of the nodes contained within the chosen component.

When nodes is selected, use the switch to change the selection mode.

nodes

Select individual nodes.

faces_edges_nodes

faces

Select all of the nodes on 2D and 3D faces.

If there are discontinuities on a 2D face, then only the nodes inbetween the discontinuities will be selected.

faces_edges_faces_nodes

2D faces ext

Select all of the nodes on a 2D face that contain discontinuities.

faces_edges_2d_face_ext_nodes

loops

Select all of the nodes on continuous free edges that make a closed loop simultaneously, such as the perimeter of a hole.

Only valid for SHELL elements.

faces_edges_loops_nodes

free edges

Select all of the nodes on free edges of elements.

If there are discontinuities on an edge, then only the nodes on the free edges inbetween the discontinuities will be selected.

Only valid for SHELL elements.

faces_edges_free_edges_nodes

free edges ext

Select all of the nodes on free edges of elements that contain discontinuities.

Only valid for SHELL elements.

faces_edges_free_edges_ext_nodes

edges

Select all of the nodes on free edges or shared edges (butt joints, L/corner joints, and T-joints) of elements.

If there are discontinuities on an edge, then only the nodes on the edge inbetween the discontinuities will be selected.

Only valid for SHELL elements.

faces_edges_edges_nodes

edges ext

Select all of the nodes on free edges or shared edges (butt joints, L/corner joints, and T-joints) of elements that contain discontinuities.

Only valid for SHELL elements.

faces_edges_edges_ext_nodes

value =

This switch actually presents a very different set of options depending on what you pick:

•	value =: Specify a numerical magnitude for the pressure.

•	constant components: Specify the X, Y, and Z components; the resulting pressure vector will be derived from these components.

•

curve, vector: This option for pressures that are time-dependent lets you specify the time history of the pressure using a vector entity.
When using this option, you may choose to apply the pressure normal to the elements, or use the plane and vector selector to specify a direction.
The curve selector is used to select the curve representing the load time history. This curve must already exist in the model.
The optional scale factor field allows you to scale the X vector of the curve.
Curves can be viewed and modified from within the XY Plots module.

•

curve, components: Type in the X, Y, and Z components to define the direction and magnitude--for example, (2,2,2) will be twice the magnitude of (1,1,1). Next, click the curve field twice to select from a list. Finally, specify a factor for the curve’s xscale.
Curves can be viewed and modified from within the XY Plots module.

•	equation: type the loading equation into the entry field that displays.

Equations allow you to create force, moment, pressure, temperature or flux loads on your model where the magnitude of the load is a function of the coordinates of the entity to which it is applied. An example of such a load might be an applied temperature whose intensity dissipates as a function of distance from the application point, or a pressure on a container walls due to the level of a fluid inside.

Functions must be of the form magnitude= f(x,y,z). The only variables allowed are x, y and z, (lower case) which are substituted with the coordinate values of the entity to which the load is applied. In the case of grid point loads (force, moment or temperature) the grid point coordinates are used. For elemental loads (pressure or flux) the element centroid coordinates are used. In the event that a cylindrical or spherical coordinate system is used, x, y and z are still used to reference the corresponding direction. Standard mathematical operators and functions can be used; however, any functions requiring external data will not be valid. See Functions and Operators for a complete list.

Note:

If your equation contains a syntax error, no warning message will be displayed, but any loads created will have a zero magnitude.

Examples:

A flat plate, 20 x 20 units, lying in the X-Y plane with the origin at the center. A linear function for an applied force
magnitude = 20 – (5*x+2*y):

load_equations_ex1

The same plate with a polynomial function

magnitude = x^2-2y^2+x*y+x+y:

load_equations_ex2

A curved surface with a polynomial function for an applied pressure magnitude = -((x^2+2*y^2+z)/1000). The pressure function is defined in terms of the cylindrical coordinate system displayed at the top edge of the elements.

load_equations_ex3

•	Linear interpolation: Use this option this to interpolate pressures from a saved file or existing loads.

Note:

Linear interpolation only works with shell elements.

Each row of the input file contains the pressure's x,y,and z coordinates followed by its magnitude. The data can be separated by a space or tab. Loads from files formatted as CSV (Comma Separated Values) or SSV (Space-Separated Values) text files can be interpolated.

You can then select the desired elements to which you wish to add loads, and pick 3 or more existing loads that enclose those elements. When you interpolate, a linear function is used to create additional loads on the selected elements, with magnitudes based on the magnitudes of the loads that you had selected:

pressures_linearinterpolate

The search radius is a search distance to find the loads which are within that distance from a centroid or node on which a load is being interpolated. The nearest 3 loads located within that distance are used to create the load at the centroid or node by linear interpolation. Linear interpolation uses a triangulation method, so if it finds fewer than 3 loads within that distance no interpolation takes place. While reading the initial loads from a file, if linear interpolation is not possible because the search radius is too small, the original loads are simply applied to the nearest centroid or node.

•

To interpolate and extrapolate pressures from existing loads, select field loads. You can then select the desired elements to which you wish to add loads, and any existing loads on which you wish to base additional forces. Field Loads will not overwrite any existing loads, so you can create an area of loads via linear interpolation and then use field loads to expand the load area without changing the loads already inside of the area.

When you create, HyperMesh uses a Green’s function with the given boundary loads in order to create the loads on all of the selected elements. For smoothness, the gradient at the boundary points is enforced to be zero. This ensures that the extrapolated loads remain lower than the input loads. For this reason it is recommended to use representative boundary values as input to be able to capture the peaks reasonably.

Note:

This version differs from linear interpolation both in the way that the load magnitudes are determined, and also in the fact that it can be applied to elements outside the boundaries of the chosen existing loads.

relative size / uniform size

This setting does not affect the temperature load, only the length of its graphical indicators. Use the toggle to choose between these options, then type in a numeric value.

•	relative size = display temperatures in a size relative to the model size (default 100).

•	uniform size = display all temperatures with the same size.

label loads

Choose whether or not to use text labels for each load.

load types

Click the button and pick the desired load type from the list. Available options depend on the current solver profile.

face angle / individual selection

Face angle

Value used to determine which of the selected elements are to have temperatures applied. For temperatures applied to faces, once the starting face has been identified, the normals of the adjacent remaining faces are tested. If the angle between the normals is less than the face angle, a temperature is applied to the adjacent element. This process continues until all of the free faces have been tested. For a temperature applied to edges, the process is similar except that the angle between edges is used instead of the angle between faces.

Only available when the entity selector is set to nodes and the selection mode is set to faces, 2d faces ext, free edges, free edges ext, edges, or edges ext.

Individual Selection

Select individual elements on a face or select individual free/shared edges of elements.

Only available when the entity selector is set to nodes and the selection mode is set to faces, free edges, or edges.

edge angle

Splits edges that belong to a given face.

When the edge angle is 180 degrees, edges are the continuous boundaries of faces. For smaller values, these same boundary edges are split wherever the angle between segments exceeds the specified value. A segment is the edge of a single element.

Only available when the entity selector is set to nodes and the selection mode is set to free edges, free edges ext, edges, or edges ext.

Panel Inputs

Input

Action

loads

Use this collector to select the loads you wish to modify.

value =

This switch actually presents a very different set of options depending on what you pick:

•	value =: Specify a numerical magnitude for the pressure.

•	constant components: Specify the X, Y, and Z components; the resulting pressure vector will be derived from these components.

•

curve, vector: This option for pressures that are time-dependent lets you specify the time history of the pressure using a vector entity.
When using this option, you may choose to apply the pressure normal to the elements, or use the plane and vector selector to specify a direction.
The curve selector is used to select the curve representing the load time history. This curve must already exist in the model.
The optional scale factor field allows you to scale the X vector of the curve.
Curves can be viewed and modified from within the XY Plots module.

•

curve, components: Type in the X, Y, and Z components to define the direction and magnitude--for example, (2,2,2) will be twice the magnitude of (1,1,1). Next, click the curve field twice to select from a list. Finally, specify a factor for the curve’s xscale.
Curves can be viewed and modified from within the XY Plots module.

•	equation: type the loading equation into the entry field that displays.

Equations allow you to create force, moment, pressure, temperature or flux loads on your model where the magnitude of the load is a function of the coordinates of the entity to which it is applied. An example of such a load might be an applied temperature whose intensity dissipates as a function of distance from the application point, or a pressure on a container walls due to the level of a fluid inside.

Functions must be of the form magnitude= f(x,y,z). The only variables allowed are x, y and z, (lower case) which are substituted with the coordinate values of the entity to which the load is applied. In the case of grid point loads (force, moment or temperature) the grid point coordinates are used. For elemental loads (pressure or flux) the element centroid coordinates are used. In the event that a cylindrical or spherical coordinate system is used, x, y and z are still used to reference the corresponding direction. Standard mathematical operators and functions can be used; however, any functions requiring external data will not be valid. See Functions and Operators for a complete list.

Note:

If your equation contains a syntax error, no warning message will be displayed, but any loads created will have a zero magnitude.

Examples:

A flat plate, 20 x 20 units, lying in the X-Y plane with the origin at the center. A linear function for an applied force
magnitude = 20 – (5*x+2*y):

load_equations_ex1

The same plate with a polynomial function

magnitude = x^2-2y^2+x*y+x+y:

load_equations_ex2

A curved surface with a polynomial function for an applied pressure magnitude = -((x^2+2*y^2+z)/1000). The pressure function is defined in terms of the cylindrical coordinate system displayed at the top edge of the elements.

load_equations_ex3

•	Linear interpolation: Use this option this to interpolate pressures from a saved file or existing loads.

Note:

Linear interpolation only works with shell elements.

Each row of the input file contains the pressure's x,y,and z coordinates followed by its magnitude. The data can be separated by a space or tab. Loads from files formatted as CSV (Comma Separated Values) or SSV (Space-Separated Values) text files can be interpolated.

You can then select the desired elements to which you wish to add loads, and pick 3 or more existing loads that enclose those elements. When you interpolate, a linear function is used to create additional loads on the selected elements, with magnitudes based on the magnitudes of the loads that you had selected:

pressures_linearinterpolate

The search radius is a search distance to find the loads which are within that distance from a centroid or node on which a load is being interpolated. The nearest 3 loads located within that distance are used to create the load at the centroid or node by linear interpolation. Linear interpolation uses a triangulation method, so if it finds fewer than 3 loads within that distance no interpolation takes place. While reading the initial loads from a file, if linear interpolation is not possible because the search radius is too small, the original loads are simply applied to the nearest centroid or node.

•

To interpolate and extrapolate pressures from existing loads, select field loads. You can then select the desired elements to which you wish to add loads, and any existing loads on which you wish to base additional forces. Field Loads will not overwrite any existing loads, so you can create an area of loads via linear interpolation and then use field loads to expand the load area without changing the loads already inside of the area.

When you create, HyperMesh uses a Green’s function with the given boundary loads in order to create the loads on all of the selected elements. For smoothness, the gradient at the boundary points is enforced to be zero. This ensures that the extrapolated loads remain lower than the input loads. For this reason it is recommended to use representative boundary values as input to be able to capture the peaks reasonably.

Note:

This version differs from linear interpolation both in the way that the load magnitudes are determined, and also in the fact that it can be applied to elements outside the boundaries of the chosen existing loads.

relative size / uniform size

This setting does not affect the temperature load, only the length of its graphical indicators. Use the toggle to choose between these options, then type in a numeric value.

•	relative size = display temperatures in a size relative to the model size (default 100).

•	uniform size = display all temperatures with the same size.

label loads

Choose whether or not to use text labels for each load.

load types

Click the button and pick the desired load type from the list. Available options depend on the current solver profile.

The following action buttons appear throughout the subpanels:

Button	Action
create	Creates the new load
create/edit	Creates the new load and opens its property card in edit mode.
reject	Reverts the most recent load creation.
review	Click this button, then pick the temperatures you want to review on your model. After you pick each temperature, the value of the temperature is displayed.
update	Changes the selected load(s) to use the currently-specified characteristics.
return	Exits the panel.

See Also:

Loads on Geometry

Alphabetical List of Panels