Comment by peter_d_sherman

https://www.comsol.com/paper/image/66162/big.png

From the following paper:

"Electromagnetic Simulation of Split-Core Current Transformer for Medium Voltage Applications" by N. Paudel, V. Siddharth, S. Shaw and D. Raschka (2018)

https://www.comsol.com/paper/electromagnetic-simulation-of-s...

Related:

Learn everything about the Split-Core Current Transformer:

https://innovatorsguru.com/split-core-current-transformer

Video about Current Transformers:

https://www.youtube.com/watch?v=32Vw40nUSwA&t=92s