WireMag

WireMag is a C++ library for calculating the magnetic field in 3D space generated current in arbitrary wire shape.

Compile

This library uses CMake for compliation, by default using g++ (C11). To compile, make a new folder in the package directory:

mkdir build
cd build

Then call CMake to generate makefile:

cmake ..

A ‘Makefile’ will then be generated in the ‘build’ directory. To compile, just:

make

An executable ‘run’ will be generated under /build/bin, simply execute by:

./run

How it Works

To calculate the magnetic field at certain grid with certain wire shape, one has to create to first creat two object:

1. Object of class Wire: the shape of wire and it’s discritize resolution.
   There are also supplements class method to help creat common wire shapes with flexiable configuration parameters

   Wire w1;
   w1.path = *w1.solenoidPath(5.1e-3, 0.405e-3, 4, 2, 20);
   w1.pathTranslate(0, 0, -2.5e-3);
   w1.unit_length = 2e-3;
   w1.pathDiscretize();

2. Object of class Mesh: the mesh grid where the magnetic field will be calculated.
   The mesh grid creator can be used to create rectangular meshgrid:

   Mesh m;
   m.genMesh(0, -5e-3,  -5e-3, 0, 5e-3,  5e-3, 0.1e-3);
   m.save();

3. Calculate magnetic field based on Biot Savart Law. To do this pass the wire object and mesh object to class BiotSavartLaw initializer:

   BiotSavartLaw bst;
   bst.addWires(&w1);
   bst.addWires(&w2);
   bst.mesh = &m;
   bst.current = 500;
   bst.calculate();
   bst.saveWires();

4. After field data has been calculated, one can optionally choose to do post analysis, e.g. calculate the norm of the field or choose a slice for evaluation:

   bst.startAnalysis();
   //bst.sliceMeshX(0);
   bst.normField();
   bst.saveAsCSV();

Examples

Example of generated wire geometry:

Example of generated slice meshgrid:

Result of calculated field:

Status

Under development

TODO

• Make GUI window for user-firendly access
• Add plotting module using python
• Add unittest