Apparent relative permeability of a solenoid coil core

□How to Use
　Enter either the dimensional ratio (in meters) calculated as “core length ÷ core diameter,” or
　the relative permeability (μr) of the core material. The apparent relative permeability (μa) will be displayed in the far right column of the table.
　Items shown in the table other than those mentioned above are calculated during the process of determining μa. Please refer to the paper for details.

□What Can Be Inferred from the Calculation Results
・Even if a very large value (such as 10,000) is specified for the relative permeability, μa will plateau.
・When the relative permeability is set to 1, μa in the region where the dimensional ratio is greater than 1 approximates the Nagaoka coefficient (though with an error of less than 10%).
　*In addition to the above, if you have any other interesting observations, we would appreciate it if you could post them in the “Customer Feedback” section.

□Notes on Calculation Accuracy and Reliability
・Although the calculation formula includes an infinite series, setting the number of terms (n) to 11 resulted in an error of an order of magnitude that is practically negligible
　(less than 1‰); therefore, we have fixed n at 11.
　*Results for n=10 and n=11 are included for verification.
・Please note that we cannot rule out the possibility of errors in the calculation formula or results.