Optimization of an immersion cooling 46.5 kW/46.5 kWh battery module using flow resistance network shortcut method

Immersion cooling technology the most important thermal management technology. Flow organization is the crucial strategy to improve the temperature uniformity. The flow resistance network shortcut method, which is efficient for the design of fluid flow, is also a potentially appropriate method for immersion cooling optimization. This study proved its applicability in a 46.5 kW/46.5 kWh battery module thermal management design. The flow resistance network can solve the velocity field in seconds, and the maximum relative error of the solution is only 6 %. Results show that, root mean square error (RMSE) of the flow rate between the mini-channels, which indicates the flow non-uniformity, are respectively 0.11 and 0.30 for Z-flow and U-flow at a volume flow rate of 32 L/min. To improve the uniformity, the randomized controlled trial (RCT) is introduced in the design of a uniform distribution of flow structures by the battery topology arrangement. The lowest RMSE of the Z-flow and U-flow reduces to 0.04 and 0.068, respectively. Then, we establish the optimized structure design and import it into Ansys Fluent. The temperature uniformity for Z-type flow and U-type flow is improved by 16.45 % and 56.16 %, respectively. The abovementioned method provides an efficient optimization for large-scale Battery thermal management system (BTMS) flow structure design.