GENERATION OF ONE DIMENSIONAL ELEMENTS ON THE PARALLEL BRACKET

OBJECTIVE:

1. How to create different types of one dimensional elements.
2. Getting familiar with the one dimensional menu bar.

PROCEDURE:

Creating a Rod element with only translational degree of freedom and RBE2 link -

• Import the IGES file using the import geometry option under import solver deck tool.
• To represent the enitre 3D component as a surface, create a midsurface from the given model. Go to geometry menu page and select the midsurface tool to extract a midsurface.
• Create components and put midsurface in different components to toggle the properties independently. We can do this by clicking right mouse button in tab bar and select create option from the drop down menu.
• Create material and property for the brackets by clicking right mouse button in the tab bar. Provide card image as PSHELL, thickness as 2mm and we can create steel as material.
• Provide washers split to the holes by clicking on quick edit tool. Take offset as 5 units.
• Generate a 2D mesh by automesh tool in the two dimensional menu page. Put the element size as 5 units and mesh type as mixed. Select the whole surface and hit the mesh button to create the mesh.
• Define property for ROD as well, provide card image as PROD, steel as material and 'boxsection' as beamsection.
• Hyperbeam is used to create beam cross sections.Click Hyperbeam and check the standard section radio button and select hyperbeam as standard section library and "thinwalled box" as standard section type.Pressing the create button will take you to hyperbeam. Fill the dimensions a=12mm, b=10mm and t=0.75mm. Click the model view button to get back in hyperworks.
• Now to create an RBE2 element press the rigids tool button in the 1D menu panel. To create multiple elements(RBE2 Links) select multiple nodes and calculate nodes in sub-options. Provide the translational degree of freedom by unchecking the box. Select the nodes around the holes and press create button to generate RBE2 links.
• Select rods tool in 1D menu page to create a rod element. Select the nodes and put element type as CROD & property rod to create the rod element.

BAR, ROD & BEAM ELEMENTS

Define a Beam element with all Degree of freedoms and RBE3 link-

• Create property for beam similar to as we did for rod. PBEAM as card type, steel as material and 'I section' as beamsection.
• Now click Hyperbeam and check the standard section radio button and select hyperbeam as standard section library and "standard I section" as standard section type. Pressing the create button will take you to hyperbeam. Fill the dimensions a=8mm, b=10mm, c=8.5mm, t1=0.75, t2=0.6, t3=0.6. Click the model view button to get back in hyperworks.
• To create an RBE3 link press the rigids tool button in the 1D menu panel. To create multiple elements(RBE3 Links) select multiple nodes and calculate nodes in sub-options. Provide the degree of freedoms by unchecking the box. Select the nodes around the holes and press create button to generate RBE3 links.
• Select beams tool in 1D menu page to create a beam element. Select the nodes and put element type as CBEAM & give property beam to create the beam element. Select nodes to provide orientation as well.

Cross-section of different one dimensional elements

Generate a Bar element with only X and Y DOF's and RBE3 links-

• Firstly we need to create property for Bar element. Click right mouse button in the tab bar and enter PBAR as card type, steel as material and 'standard channel' as beamsection.
• Click Hyperbeam and check the standard section radio button and select hyperbeam as standard section library and "standard Channel" as standard section type. Pressing the create button will take you to hyperbeam. Fill the dimensions DIM1=5mm, DIM2=1.2mm, DIM3=10mm and DIM4=1.2mm. Click the model view button to get back in hyperworks.
• To create an RBE3 link press the rigids tool button in the 1D menu panel. To create multiple elements(RBE3 Links) select multiple nodes and calculate nodes in sub-options. Provide the degree of freedoms by unchecking the X and Y dialog box. Select the nodes around the holes and press create button to generate RBE3 links.
• Select bars tool in 1D menu page to create a bar element. Select the nodes and put element type as CBAR & give property bar to create the bar element. Select nodes to provide the orientation as well.

One dimensional spring elements

Apply the mass of magnitude 10 with RBE2 link-

• Create an RBE2 element by pressing the rigids tool button in the 1D menu panel. To create multiple elements(RBE2 Links) select multiple nodes and calculate nodes in sub-options. Provide the translational degree of freedom by unchecking the box. Select the nodes around the holes and press create button to generate RBE2 links.
• Now to create mass select masses tool in the 1D menu page. Select the node on which you want to provide mass.
• Define property corresponding to the node i.e BRACKET_1 as in our case. Give Element type as CMASS1 and mass magnitude as 10units. Hit the create button to generate the mass.

Join the two components with Spring Elements-

• Select the Springs tool in the 1D menu page. Then, Select end nodes where you want to create spring element.
• Choose element type as CELAS1 to create the spring element.

CONCLUSION:

1. Got an understanding about one dimensional elements creation.
2. Achieved the desired elements type with proper cross-section.