Using Ansys Simulation for Multiphysics Challenges in Axial Flux Motor Development
Written by Claudiu COTOVANU
4MULTIPHYSICS
4MULTIPHYSICS is a fast-growing engineering company based in Cluj-Napoca, Romania, focused on the design and optimization of electric machines. With deep expertise in mechanical design, CFD, structural and dynamic simulations, the company specializes in advanced multiphysics analysis. It operates independently using high-performance computing infrastructure and is active in both commercial engineering services and European R&D consortia.
Task Description
As part of the European MAXIMA project, 4MULTIPHYSICS took on the task of designing a high-efficiency axial flux electric motor for the automotive industry. The goal was to create a cost-effective and environmentally sustainable electric machine with reduced reliance on critical raw materials. The project presented complex engineering challenges, including high power density requirements, thermal management in compact volumes, and mechanical reliability under dynamic loading.
Pic. 1 Radial flux vs. axial flux
Solution
ANSYS Fluent and CFX: These tools were used to model and solve coupled thermal and fluid problems in the axial flux motor architecture. CFD simulations helped design and optimize possible cooling strategies in line with the application’s thermal constraints.
ANSYS Mechanical: Used to evaluate and optimize the rotor’s structural behavior under high centrifugal forces and axial loads, supporting reliable operation during extreme duty cycles.
Rolling Bearings Inside Ansys: Enabled the implementation and simulation of a complex bearing arrangement, allowing assessment of its impact on rotor dynamics, axial stiffness, and overall mechanical performance under variable thermal and rotational conditions.
Pic. 2: Trapped stator between the rotors
Benefits
20% reduction in motor losses compared to a reference motor from 2020, contributing to increased system efficiency.
2% improvement in WLTP consumption through smart motor control based on the digital twin model.
Projected 32% reduction in CO₂-equivalent emissions, driven by lower operational losses, reduced aluminium use, and improved magnet recyclability.
Achieved a target manufacturing cost below €6/kW, making axial flux motors viable beyond niche applications.
Pic. 3: Rotor design for the dual-stator topology