The method for calculating magnetic field induced by current coils

In the simulation of electromagnetic fields in particle accelerators, it is often required to calculate the field from the coils with the current. For this one can use the Biot-Savart law. The paper presents a method for calculating the field from coils with the current, in the case where the coils can be represented in the form of a body formed by extrusion of a constant section along a smooth curve. The formulas that allow transforming the integral over the body of the current coil to the integral along the extrusion curve are presented. The analysis of the effectiveness of the proposed approach is given.