PC Micromagnetic Simulator Frequently Asked Questions


Q: What is PC Micromagnetic Simulator/SimulMag?
A: PC Micromagnetic Simulator (also known as SimulMag) is easy to use software for calculating a magnetic system of interacting objects using a single-domain approximation. This is a very brief summary of its capabilities. Visit http://math.nist.gov/oommf/contrib/simulmag/ for a fuller description of SimulMag.

Q: Is it a true three-dimensional program?
A: Yes. The full three-dimensional magnetization and field vectors are taken into account in the calculations. The geometric layout of the system being designed and the magnetization vectors of the elements making up a system are displayed in three dimensions.

Q: What magnetic calculation engine does it use?
A: SimulMag uses single-domain models to calculate the magnetic behavior of individual elements. Static and dynamic calculations are implemented. The static calculation is based on a semi-analytical Stoner-Wohlfarth model, while the dynamic method solves the Landau-Lifshitz torque equations. The elements interact via magnetostatic interactions and user specified exchange interactions. Fields due to applied currents are taken into account in the calculations. A complete description of the mathematical implementation of the physical model that represents the electromagnetic calculation aspects of the software can be found in Chapter 4 of the user's manual.

Q: How much hard drive space does it take?
A: SimulMag version 1.0 takes up about 1 megabyte of hard disk space when installed.

Q: How much RAM does it need?
A: A minimum of 4 megabytes of RAM is required.

Q: What operating system do I need (Win95, NT, Win31, OS2, UNIX)?
A: The operating systems Windows 95 and Windows NT 3.51 or higher are required to run SimulMag.

Q: What language was it written in?
A: SimulMag was written in Microsoft Visual Basic Version 5.0.

Q: Which is the best demo example?
A: The viewer software MMS Viewer, which is available for download from the web site, can be used to view designs and simulations created with the simulator, including viewing them online. An animation of recorded simulations is played back when loaded in the viewer. Several design examples illustrating the various capabilities of the software are available at http://math.nist.gov/oommf/contrib/simulmag/examples/examples.html.

Q: Do I really need to download the manual, or is it pretty easy to figure out?
A: Like most Windows programs, the workings of SimulMag is fairly easy to figure out without the user's manual. But familiarity with the user's manual will almost always be necessary in order to accomplish advanced designs and simulations and in interpreting generated output data. Every new user is encouraged to review the Section 2.4, "Design Example," in the user's manual.

Q: When I load an input file by double-clicking on it from my Windows desktop, a design and/or simulation get displayed, but I am unable to modify the design further or run a new simulation. What is happening?
A: In the Windows environment, the input files (the ones with the extension ".mms") are associated with the viewer program (MMS Viewer) and NOT with the simulator. As a consequence, if the viewer is already installed on your computer and you click on any of the input files in your desktop area, the viewer gets invoked. You cannot use the viewer to modify the contents of the files, because it merely reads and displays them. You use the simulator program (SimulMag) instead to accomplish a design and simulation. The viewer program can effectively be used as a browser plug-in for convenient online display of design examples that are posted on the Web. Any design so viewed can be stored to a local file using the viewer's main menu.

Go to PC Micromagnetic Simulator main page.


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Date created: February 10, 1999 | Last updated: April 27, 2011    Contact: Webmaster