Multiphysics Simulation Helps Miele to Optimize Induction Stove Designs

Christian Schröder
mieletec FH Bielefeld

Holger Ernst

The induction stove was designed to meet a consumer need for better precision and speed than traditional stoves. Designers were tasked with improving the energy efficiency of the induction coils-stovepot interaction considering both the thermal and electromagnetics of the system.

Miele, a world leader in domestic appliances and commercial machines, along with researchers from mieletec FH Bielefeld, used simulation to improve, verify, and optimize induction stove designs. To streamline the design process, Miele set out to reduce the number of prototypes. The engineers needed to deal with certain challenges in the design. For instance, the electrical current produces a troublesome high-pitched noise. In addition, the interaction of cookware with the coils’ magnetic field results in an attraction force that causes the cookware to move around when placed on the stovetop.

In order to obtain an accurate description of the induction stove-pot system, Miele solved for heat transfer together with the electromagnetic fields, and optimized to determine the best operating conditions. By using a parametric sweep simulating different alternating current frequency-coil geometry scenarios, they came up with a design that is almost silent to the human ear. Miele also simulated magnetic forces and found a configuration where the resulting net force does not cause the pot to move across the stove. With COMSOL Multiphysics, Miele was able to reduce their number of experiments by 80%, saving money and time.

The comparison between COMSOL Multiphysics results (magnetic flux density norm) and experimental field lines shows that simulation is accurate and can be used to test other coil designs before building a prototype.