Below we present a simple script for calculating the static deflection of a beam with a variety of boundary conditions and load types. The finite element method is implemented using Python with the numpy library and plot are made using matplotlib. This code can be easily modified for other boundary conditions or loads.
We often want to incorporate a finite-element solve into a larger program for design automation or optimization. The example below includes a Python function that runs an APDL script and then checks the output file for errors.
In a previous post, we built a quick model for eddy currents in a plate stationary in a time-varying magnetic field. Here we examine the induced currents and damping force that result from motion of the plate relative to the magnetic field.
In electric machines, there are two common causes of eddy currents: (1) time-varying currents in coils, and (2) motion of conductors relative to sources of magnetic field. In this post, we show how to estimate the current density arising from a time-varying magnetic field passing through a plate.
In this article, we compare the performance of a tuned-mass damper mounted at the end of a cantilever beam to the Lanchester damper which was shown in the previous article. The classic single-degree-of-freedom (SDOF) tuned-mass damper is sketched in the figure below. The design approach is to find the equivalent SDOF system for the cantilever beam’s mode of interest and then use the design formulas for an optimal SDOF TMD to determine the stiffness and damping of the absorber.
In this article, we show the robust and broadband performance of a Lanchester damper applied to a cantilever beam and how it achieves good performance without tuning and good performance over a number of modes, not just the primary mode.
Commonly, we need to save results from an Ansys Workbench study as a text file for post-processing in another program, such as Excel. One can right-click on a desired result and use Export, but that can be tedious if there a lot of results to save. With a snippet one inserts a Commands (APDL)object in the solution and writes APDL code to perform the desired functions.
For a bonded contact, which is the default for models opened in Ansys Workbench Mechanical, the contacts are modeled using elements TARGE170 and CONTA174. The thermal conductivity and stiffness of the contact elements are calculated by Ansys based on the properties of the two bodies. The controls only allow one to change the contact stiffness factor FKN which is a multiplier but not the actual stiffness of the joint (ie with SI units of N/m/m^2). However if one would like to set the value of the contact stiffness or thermal contact resistance, it can be done using Command snippets (also known as the Commands Object) for each contact. Continue reading Setting Mechanical Contact Stiffness and Thermal Contact Conductivity Values in Ansys Workbench using Command Snippets→