Energy Functions Form

Use the Energy Function form to specify the parameters for displaying functions of input, kinetic, potential, model damping, link damper, link hysteretic, and error energy.

Choose the energy functions to be displayed by checking the check boxes.

- Input Energy check box. Work done on the structure by force and acceleration functions. In an exact solution, this would equal the sum of the Kinetic, Potential, Modal Damping, Link Damper, and Link Hysteretic energies.
- Kinetic Energy check box. A function of the sums of the masses and their corresponding velocity for the structure.
- Potential Energy check box. A function of the sums of the elastic constants and their corresponding displacement for the structure. The sum includes NLLink members.
- Modal Damping Energy check box. The energy absorbed through model damping.
- Link Damper Energy check box. The energy absorbed through NLLink damping.
- Link Hysteretic check box. The energy absorption by Plastic 1, Isolator1 and Isolator2 NLLink elements. Damper, Gap and Hook NLLink elements are not included.
- Error Energy check box. An estimate of the error in the analysis. It is the difference between the input energy and the sum of the remaining energy components.

Click the OK button to complete the definition of the energy plot function and return to the Plot Function form.
Define another function, or click the OK button to return to the Plot Function Trace Display Definition form. Refer to the Plot Functions topic for the additional steps required to display the energy plot function.

Access the Energy Functions form as follows:

Define a Time History function and a Time History Load case and run an analysis.
Click the Display menu > Show Plot Functions command to display the Plot Function Trace Display Definition form.
Click the Define Plot Functions button to display the Plot Functions form.
Select the Add Energy Functions option and click the Add Plot Function button to display the Energy Functions form.
Select the Add Energy Functions option from the Choose Function Type to Add drop-down list and click the Add Plot Function button, or highlight a previously defined energy function definition and click the Modify/Show Plot button to display the Energy Functions form.