A master programme thesis from Aalborg University
Numerical Modeling of Degas in EV Battery Cooling Plates: A Multiphase CFD Study
Author(s)
Term
4. term
Education
Publication year
2025
Submitted on
2025-05-27
Pages
72 pages
Abstract
Efficient thermal management in electric vehicles (EVs) is critical to battery performance and safety. Liquid-cooled battery plates are commonly used, but the presence of trapped air bubbles during coolant filling can degrade heat transfer and lead to localized overheating. This study presents a numerical framework for simulating the degassing process in EV battery cooling plates using the Volume of Fluid (VOF) method in STAR-CCM+. The model is validated against experimental data with image-based bubble detection, resulting in a correlation of 75% in the number of bubbles and 99% of total remaining air in the system. A comparison of three turbulence models (URANS, LES, DES) showed consistent air entrapment predictions, with LES providing the highest resolution of turbulent structures. Additionally, velocity magnitude was identified as an effective single-phase indicator for predicting regions prone to air retention, reducing computational cost of more than 90% in early-stage design evaluation. Design modifications informed by simulation results demonstrated improved degassing performance. The proposed framework enables reliable analysis of air removal in battery cooling systems and supports the optimization of geometry without extensive physical testing.
Keywords
CFD ; VOF ; Multiphase ; Image Processing ; Cooling Systems ; Bubbles ; Automotive ; Turbulence Modeling ; EVs
Documents
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