Experimental study on the heat transfer and flow characteristics of phase change slurry in topology optimization cold plate

Liquid cooling with cold plates offers an efficient solution for battery thermal management. However, the geometric limitations of traditional cold plate designs and the limitations of conventional single-phase fluids relying on the sensible heat for heat storage hinder its practical application. This study addresses these challenges by combining the topology optimization cold plate (TCP) with phase change slurry (PCS), and experimentally investigates its adaptability at both design and off-design conditions. An experimental platform is established to comprehensively investigate the thermal energy storage characteristic of PCS and the effects of cold plate configuration, inlet temperature, volume flow rate and mass concentration on the flow and heat transfer characteristics of PCS in TCP. The results demonstrate that the PCS demonstrates superior thermal energy storage performance compared to water, primarily attributed to its enhanced latent heat absorption capacity. TCP achieves an 8.6 °C reduction for the maximum temperature compared to the rectangular channel cold plate (RCP). The PEC number for TCP is 1.3 times that of RCP at 20 wt% PCS, highlighting its overall better performance in heat transfer enhancement and flow resistance reduction at both design and off-design conditions. At 24 °C, 20 wt% PCS achieves the lower T_ave and T_δ due to effective heat absorption during phase change process even at the off-design condition. As the Q_v increases, the influence of mass concentration on the average temperature diminishes. At both design and off-design conditions, all the flow resistance factors of PCS are larger than that of pure water, attributing to the increase of PCS viscosity. This study can provide experimental support and technical reference for further research and practical application.