Prev Chapter 6: Multi-Step Analysis Up Chapter 6: Multi-Step Analysis Subsection 6.1.1: Boundary Conditions Next
6.1 The Step Section
The multi-step analysis feature organizes the input file in a slightly different way: the Control section is no longer defined at the top of the file, and instead, a new Steps section is added to the bottom of the file, which will contain a list of analysis steps. Each analysis step requires its own step sub-section. In this step section, the user can redefine the control section, boundary section, loads, contact, and other model components. The following format is suggested when defining a multi-step analysis:
<febio_spec version="3.0"> <Module type="solid"/> <Material> <!-- materials go here --> </Material> <Mesh> <!-- mesh definition goes here --> </Mesh> <MeshDomains> <!-- mesh domains goes here --> </MeshDomains> <Boundary> <!-- global boundary conditions --> </Boundary> <LoadData> <!-- load curve data goes here --> </LoadData> <Steps> <step> <Control> <!-- local control settings --> </Control> <Boundary> <!-- local boundary conditions --> </Boundary> </step> </Steps> </febio_spec>
The first part of the file looks similar to a normal input file, except that the control section is not specified. Also, the Boundary, Loads, Constraints, Contact, sections should only contain global boundary conditions, i.e. boundary conditions that will remain active in all analysis steps.
At the end of the file the user defines as many step sections as needed. In each step section, the user can now define the control parameters and model components.