Analysis of the thermal management of electric vehicle charging inlet dependence on the material properties

The demand for quick charging of the electric car causes an increase in the value of the electric current, which results in the requirement of safe thermal management due to a temperature rise. The research presented was aimed on validation whether proposed charging inlet thermal monitoring system solution meets the safety requirements and to which extend the system depends on the material properties. Experimental and numerical analyses of the steady and transient charging process of the prototype unit were conducted for a system containing a new type of material, namely elastomer. Physical properties of this material were measured by the authors and applied in the numerical model, which improved the results by 14–56%. Agreement with the experimental data at level of 67–98% was obtained (in comparison to original 45–86%). The numerical analysis was conducted in Simcenter FloEFD. Temperature value correspondence changed from 3.6 K to 2.2 K for steady-state scenario and from 13.2 K to 3.1 K for transient scenario. The high alignment with experiment was possible to achieve due to taking into account the influence of compressibility on the thermal conductivity value. It changed about 50% (from 1.6 W/(m∙K) to 0.8 ± 0.4 W/(m∙K)) when the elastomer was compressed by 8–10% level. Due to research conducted, the potential of elastomer for thermal control of the charging inlet was confirmed. Moreover, a tool for the analysis of the thermal control system of the electric car charging inlet was constructed. It takes into account the importance of material properties and enables quick validation of the designed inlet toward its level of readiness and safety.