This paper was presented at the 2024 ASPE Annual Conference in Houston, Texas.
All posts by Samir Nayfeh
Paper on Passive Magnetic Springs
This paper was presented at the 2025 ASPE Annual Conference in San Diego, CA.
Automating ANSYS APDL Execution Using Python
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.
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Eddy Currents Induced by Motion Through a Magnetic Field
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.
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Eddy Currents Induced by a Time-Varying 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.
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Setting Views and Lighting in ANSYS CFD Post
This post shows how to set exact view orientation, zoom, pan, and lighting in CFD post. This is especially useful for making consistent figures for reports or presentations.
This picture below is a stream-ribbon visualization of a swirling flow, viewed using the built in “Isometric View (Z up).” The view is centered too low and the lighting angle is not favorable.
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Design of Constraint Systems Based on Minimax Properties of Eigenvalues
There is a neat correspondence between the mathematical concept of a constraint and the practice of exact-constraint or kinematic machine design. This leads to some really useful insight for people designing machines with dynamics in mind. The PDF below is the extended abstract for a paper that Justin presented in Austin last week at the ASPE annual meeting.
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Expansion and Stiffness of Thin Adhesive or Rubber Layers
Thin layers of adhesive, plastic, or rubber are often employed in precision machines for joining, shimming, and sealing. These layers are often the most compliant and most dimensionally unstable elements of an assembly, so it is important to understand their behavior.
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Strain, Speed, and Microslip
Microslip in rolling motion is often very complicated, but the net effect can sometimes be estimated pretty easily based on strain and the resulting changes in velocity.
Units of Power Spectral Density
The power spectral density (PSD) is one of the primary ways we characterize random or broadband signals. In many cases, a PSD is read from a signal analyzer and used qualitatively to describe the frequency content of a signal. But to do anything quantitative with a PSD, we need to understand its units.
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