Ansoft HFSS Solids Menu

Transcription

1 Ansoft HFSS Use the commands on the Solids menu to: Draw simple 3D objects such as cylinders, boxes, cones, and spheres. Draw a spiral or helix. Sweep a 2D object to create a 3D object. 2D objects can be swept: Along a vector that you enter. Around the x-, y-, or z-axis. Along an open or closed 2D or 3D polyline (optionally, with a twist). Unite, intersect, split, or subtract 3D objects to create more complex objects. Cover 3D sheet objects to create 3D solids. When you choose Solids from the menu bar, the following menu appears: Maxwell Online Help System 162 Copyright Ansoft Corporation

2 Ansoft HFSS The commands in the Solids menu do the following: Box Draws a rectangle. Cylinder Draws a cylinder. Helix Draws a 2D or 3D helix by sweeping an existing 2D object (polyline or sheet). Sweep Draws a 3D object by sweeping a 2D object: Around Axis Around the x-, y-, or z-axis. Along Vector Along a vector that you specify. Along Path Along a 2D or 3D polyline. Along Path with Twist Along a 2D or 3D polyline with a twist. Unite Unites two objects into a single object. Intersect Takes the intersection of two objects, creating a new object. Subtract Subtracts one object from another, creating a new object. Split Splits an object on the XY, YZ, or XZ planes to produce two new objects. Cover Surfaces Covers the open faces of sheet objects to form solids. Maxwell Online Help System 163 Copyright Ansoft Corporation

3 Ansoft HFSS Use this command to draw a rectangular 3D object. > To draw a box: 1. Choose. 2. Select the point in the active window where you wish to place the box base vertex. The coordinates of this point appear in the side window. The object in the view window changes accordingly. Alternatively, you can use the keyboard to enter the coordinates of this point in the coordinates fields. 3. Choose Enter to accept the Box Base Vertex. 4. Enter the x, y, and z dimensions of the box in the Enter Box Size field in the side window. As you enter each value, the view window displays the change in dimensions. You can click on a point in the view windows to represent the opposite vertex, but entering the values gives you a more precise and controlled box. Note: If you create a box with a zero dimension, the software creates a rectangular sheet object. 5. Enter a name for the box in the Name field. 6. Select a color from the palette. 7. Choose Enter to accept the box or choose Cancel to cancel the action. Maxwell Online Help System 164 Copyright Ansoft Corporation

4 Ansoft HFSS Use this command to create a cylinder. Cylinders can simulate coils when you subtract a smaller cylinder from a large one. > To draw a cylinder: 1. Choose. 2. Select the point in the view window where you wish to place the center of the cylinder s base. The coordinates of this point are displayed in the side window. The object in the view window changes accordingly. Alternatively, you can use the keyboard to enter the coordinates of this point in the coordinates fields. 3. Choose the Cylinder axis to define the perpendicular axis of the cylinder. The axis will automatically be defined as the axis that is perpendicular to the plane in which the base rests. 4. Choose Enter to accept the Base center. 5. Enter the radius and height of the cylinder in the Radius & Height fields in the side window. Note: If you create a cylinder with height of zero, the software creates a circular sheet object. 6. Select Num Segments to approximate the shape of a cylinder using line segments. Otherwise, it is treated as a true surface. Enter the number of segments to use when approximating a cylinder in the field under the Num Segments option. The number of segments must be greater than Enter a name for the cylinder in the Name field. 8. Select a color from the palette. 9. Choose Enter to accept the cylinder or Cancel to cancel the action. Maxwell Online Help System 165 Copyright Ansoft Corporation

5 Ansoft HFSS Use this command to sweep a polyline or sheet object to form a helix or spiral. The object that you sweep must have only straight edges. > To draw a helix: 1. Choose. A list of polyline and sheet objects in the model appears in the side window. Warning: Keep the following in mind when creating a helix: The object you select to sweep for the helix must be a segmented object. You cannot use an object with a true surface, such as an arc or spline. The objects you sweep to form the helix are deleted. 2. Select the object to sweep. The name of the object appears in the Helix Profile box. 3. Choose OK at the bottom of the list to select the item or Cancel to cancel the action. The following window appears: More 4. Select the Helix Axis. This is the axis about which the helix spirals. 5. Specify the Turn direction. This corresponds to the right-hand rule. Maxwell Online Help System 166 Copyright Ansoft Corporation

6 Ansoft HFSS 6. Enter the pitch of the helix in the Helix Pitch field. This is the distance between successive turns of the helix. The units for pitch are those you specified for the model. 7. Enter the Number of turns in the helix. This specifies the number of complete revolutions the object makes about the helix axis. 8. Enter the Number of segments per turn. The system approximates the curved surfaces of the helix using segments. This specifies the number of segments to use approximating each turn of the helix. Generally use no fewer than 12 or no more than 36 segments per turn. 9. Enter the Radius change per turn or accept the default. This specifies the amount to increase or decrease the radius of the helix each turn. The units for the radius are those you specified for the model. 10.Enter the name of the helix in the Name field. 11.Select a color from the palette. 12.Choose OK to enter the helix parameters or choose Cancel to cancel the action. The figure below shows a solid helix on the left, and a sheet helix to the right. Note that the sheet object was created with an open polyline: Maxwell Online Help System 167 Copyright Ansoft Corporation

7 /Around Axis /Along Vector /Along Path /Along Path with Twist Ansoft HFSS Use these commands to create a 3D object by sweeping a 2D object. Around Axis Along Vector Along Path Along Path with Twist Around the x-, y-, or z-axis. Along a vector that you specify. Along an open or closed 2D or 3D polyline. Along an open or closed 2D or 3D polyline with a twist. 2D objects that can be swept into a 3D object include: 2D objects created using Lines/Circle, Lines/Arc, Lines/Rectangle, or Lines/ Polyline. 2D objects created in the 2D Modeler. 2D objects created in PlotData by saving a plot as an.sm2 file. If you sweep an open object, the resulting object will be a surface with open ends. If you sweep a sheet object, the resulting object will be a solid. The 2D object need not be orthogonal to the sweep path. Note: In Ansoft HFSS version 7, the 2D objects being swept are not preserved. Therefore, if you wish to keep a copy of the 2D objects, do the following: 1. Make a copy of the objects, using Edit/Copy. 2. Perform the sweep. 3. Paste the 2D objects back into the project, using Edit/Paste. Maxwell Online Help System 168 Copyright Ansoft Corporation

8 /Around Axis /Along Vector /Along Path /Along Path with Twist Ansoft HFSS /Around Axis Use this command to sweep a planar object around an axis. Sweeping circles around an axis is a convenient way to create an open coil loop. Before using this command, keep the following guidelines in mind: The object must lie in the plane of the axis you are sweeping around. For example, if you are sweeping an object around the z-axis, the object must lie in the xz or yz plane. The normal of the object s plane faces must be perpendicular to the axis about which you are sweeping. The object may not cross the axis about which it is being swept. > To sweep the object around an axis: 1. Choose /Around Axis. A list of profiles appears in the Profiles field. 2. Select the object you wish to sweep. You may select more than one. 3. Choose OK to select the objects. Sweep controls appear in the side window. 4. Select the axis that you wish to sweep the object around. 5. Enter the angle through which to sweep the object in the Angle of sweep field. The value must be between -360 and 360 degrees. 6. Enter the number of legs the object is swept through in the Number of Steps field. For example, enter 4 for a square shape (for 360 degrees). Leave the default value of zero for a smooth, circular sweep, which creates a true surface. 7. Enter the draft angle in the Draft Angle field. This indicates the angle at which the profile expands or contracts as it is swept. The Extended and Round options become available. Note: The Draft Angle is only available if the sweep angle is greater than -360 degrees and less than 360 degrees. 8. If necessary, choose whether the sweep values will be Extended or Round. Extended values will leave the swept object with the sharp edges of the original object, while Round values will leave the swept object with rounded edges. 9. Choose Enter to accept your values or choose Cancel to cancel the action. A new sheet or solid object is drawn in the view windows. The new object has the name and color of the original profile. Maxwell Online Help System 169 Copyright Ansoft Corporation

9 /Around Axis /Along Vector /Along Path /Along Path with Twist Ansoft HFSS /Along Vector Use this command to sweep a polyline or sheet object along a vector. Sweeping an uncovered polyline results in an open sheet object; sweeping a sheet object results in a solid. You must use the Surfaces/Cover Outline or the command to create solids from polylines and sheet objects. > To sweep the object along a vector: 1. Choose /Along Vector. A list of all visible polylines and sheet object (profiles) appears in the side window. 2. Select the objects you wish to sweep. 3. Choose OK to accept the selection. The Enter Vector fields appear. 4. Enter the x-, y-, and z-components of the vector you wish to sweep the objects along. The length of the vector appears in the Vector Length field. If necessary, enter a new vector length. The coordinates change accordingly. 5. Choose Enter to accept the sweep or Cancel to cancel the action. A new sheet or solid object is drawn in the view windows. The new object has the name and color of the original profile. The following figure shows a polyline swept to create a 3D sheet object: Maxwell Online Help System 170 Copyright Ansoft Corporation

10 /Around Axis /Along Vector /Along Path /Along Path with Twist Ansoft HFSS /Along Path Use this command to sweep a polyline or sheet along a path defined by a polyline. Sweeping an uncovered polyline results in an open object; sweeping a sheet object results in a solid. Use the Surfaces/Cover Lines or the command to create solids from sheet objects and polylines. When you are sweeping an object along a path, keep in mind that one of the endpoints of the path must lie in the same plane as the object being swept. > To sweep the object along a path: 1. Create the polyline you want to use as a path. The red path in the following figure will be used to sweep the circle at its right end: More 2. Choose /Along Path. A list of all visible polylines and sheet objects appears in the side window. 3. Select the objects you wish to sweep along a path. 4. Choose OK to select the objects. A list of the polylines appears in the side window. These polylines will form the path along which you will sweep the object. 5. Choose the polyline to sweep the profile along. The name appears in the Sweep Path field. 6. Choose OK to select the polyline. Maxwell Online Help System 171 Copyright Ansoft Corporation

11 /Around Axis /Along Vector /Along Path /Along Path with Twist Ansoft HFSS 7. Enter the draft angle in the Draft Angle field. This is the angle at which the profile expands or contracts as it is swept. Leave the draft angle set to zero if you do not want the profile to expand or contract as it is swept. 8. If necessary, choose whether the sweep values will be Extended or Round. Extended values leave the swept object with the sharp edges of the original object, while Round values leave the swept object with smooth, rounded edges. 9. Choose Enter to accept the object or choose Cancel to cancel the sweep. The new object has the name and color of the original profile. The following figure shows the result of sweeping the circle in the previous figure along a polyline: Maxwell Online Help System 172 Copyright Ansoft Corporation

12 /Around Axis /Along Vector /Along Path /Along Path with Twist Ansoft HFSS /Along Path with Twist Use this command to sweep a polyline or closed profile along a path, twisting the profiles as they are swept. This is useful when generating irregularly shaped 3D objects. Sweeping an uncovered polyline results in an open object; sweeping a sheet object results in a solid. Use the Surfaces/Cover Lines or the command to create solids from sheet objects and polylines. When you are sweeping an object along a path with a twist, keep the following things in mind: If you are twisting the object you are sweeping (there is an Angle of Twist value other than zero), the path must be smooth and continuous, without any sharp bends. One of the endpoints of the path must lie in the same plane as the object being swept. > To sweep the object: 1. Create the polyline you want to use as a path. The red path in the following figure will be used to sweep the circle at its right end: More 2. Choose /Along Path With Twist. A list of visible polylines and sheet objects appears. 3. Select the object to sweep along a path. 4. Choose OK to select the object. A list of polylines appears. One of these polylines will form the path along which you sweep the object. Maxwell Online Help System 173 Copyright Ansoft Corporation

13 /Around Axis /Along Vector /Along Path /Along Path with Twist Ansoft HFSS 5. Select the polyline to use as a path. The name of the object appears in the Sweep Path field. 6. Choose OK to accept the selection. A hand-shaped icon appears, pointing to the blank fields in the side window. 7. Enter the angle of the twist in the path in the Angle of Twist field. This is the number of degrees the profile will rotate as it is swept through the complete path. The following figure shows a circle (with 8 segments) twisted through 180 degrees. 8. Choose Enter to accept the sweep parameters or Cancel to cancel the sweep. The new object has the name and color of the original profile. Maxwell Online Help System 174 Copyright Ansoft Corporation

14 Ansoft HFSS Use this command to join two or more overlapping objects into one solid object. This command unites the objects at the point of intersection. Note: > To unite two objects: 1. Choose. A list of visible Existing solids appears in the side window. 2. Select the names of the solids that you wish to unite. The united solid retains the name and color of the first solid. 3. Choose OK to accept the objects or Cancel to cancel the action. The objects are now united into one. If the objects do not overlap, an error occurs. For example, you will not be able to unite a sphere with a cylinder if they do not touch. The objects being joined are not preserved for later use. Therefore, if you wish to keep a copy of the 2D objects, do the following: 1. Make a copy of the objects, using Edit/Copy. 2. Perform the sweep. 3. Paste the 2D objects back into the project, using Edit/Paste. Use this command to form a new object by taking the intersection of two or more objects. Note: The objects being intersected are not preserved for later use. > To intersect the objects: 1. Choose. A list of visible solid objects appears in the side window. 2. Select the solids that you wish to take the intersection of. 3. Choose OK to accept the object or choose Cancel to cancel the action. The objects vanish, leaving only the new object that was formed from the intersection. Warning: If the objects you choose to intersect do not overlap, the result is a null object and both objects vanish. Maxwell Online Help System 175 Copyright Ansoft Corporation

15 Ansoft HFSS Use this command to subtract one group of objects from another. Note: The objects being subtracted are not preserved for later use. Therefore, if you wish to keep a copy of the 2D objects, do the following: 1. Make a copy of the objects, using Edit/Copy. 2. Perform the sweep. 3. Paste the 2D objects back into the project, using Edit/Paste. > To subtract one item from another: 1. Choose. A list of visible Existing solids appears in the side window. 2. Select the solids from which you wish to subtract. 3. Choose OK to select the objects. 4. Select the names of the solids that you wish to subtract from the first. 5. Choose OK to select the objects. The second group of objects is subtracted from the first one, resulting in new objects. The new objects retain the name of the first group of objects. Intersecting box and cylinder. Box subtracted from cylinder (cylinder selected first). Maxwell Online Help System 176 Copyright Ansoft Corporation

16 Ansoft HFSS Splits objects on the xy, yz, or xz plane. If you want the section plane to be elsewhere than the global coordinate system, set your local coordinate system first using the Coordinates/Move Origin or Coordinates/Rotates commands. Note: Unlike the seemingly similar Surfaces/Section command, the split objects are not left unchanged. Also unlike the Surfaces/Section command, sheet objects can be split into more than one object. > To divide an object into smaller pieces: 1. Choose. The cursor changes to a pointing icon. 2. Select the Split plane that you will use to split the object. 3. Select which fragments you want to keep Above the split plane, Below it, or all pieces on Both sides of the plane. Any fragments not identified for keeping are discarded. 4. Choose Enter to accept the split or Cancel to cancel the action. 5. Select the names of the existing solids that you want to split. 6. Choose OK to accept the solids or Cancel to cancel the action. The objects are divided along the split plane. Use this command to cover all open areas in the sheet objects of your model. For example, if you have a hollow cylinder which has open ends, this command will cover those ends to form a solid cylinder. The open edges must form closed polylines when taken by themselves. > To cover sheet objects to form a solid: 1. Choose. A list of sheet objects appears in the side window. 2. Select the sheets you wish to cover. 3. Choose OK to accept the cover or Cancel to cancel the action. The sheet objects are now solid objects. Maxwell Online Help System 177 Copyright Ansoft Corporation