Thermal Analysis and Temperature Monitoring of a Coil for Magnetic Orientation of Steel Fibers in Cement Composites

Abstract The study presents an experimental and numerical analysis of temperature variations in a coil used for the magnetic orientation of steel fibers in cement composites. The aim of the research was to assess the thermal safety of the coil during operation and to verify the consistency between experimental measurements and numerical simulations. The test setup consisted of a multilayer coil equipped with seven thermistors placed between the winding layers, enabling real-time temperature recording during a 16-minute power supply and subsequent natural cooling. Numerical analyses were performed in the ANSYS Maxwell environment using a coupled magnetostatic–thermal model that accounted for Joule losses and natural convection. Comparison of the experimental and numerical results showed good agreement (MAE = 1.43°C, MAPE = 3.36%). A nonuniform temperature distribution was observed in the winding, with central layers heating up by approximately 15% more than the outer ones. The results indicate that the analyzed coil, without active cooling, can operate safely only in an intermittent mode. The proposed temperature monitoring method and the regression-based temperature profile description can serve as a basis for the design and thermal optimization of coils used in the magnetic orientation of steel fibers in cement composites.