Based on the application of micro-channel printed circuit heat exchangers in fields such as thermoelectric power generation and aerospace, a high-efficiency, low-resistance, and easy-to-manufacture transverse slotted channel is proposed using the theory of boundary layer re-development, and the heat transfer is enhanced. Numerical simulations are employed to study the flow and heat transfer characteristics of both straight and slotted channels. The mechanisms of heat transfer enhancement and flow resistance reduction in the transverse slotted channel are investigated. The results show that the entrance effect can significantly enhance heat transfer with a minimal increase in flow resistance. The transverse slotted channel creates multiple entrance effects in the slotted regions by inducing flow separation, which leads to periodic boundary layer redevelopment, thereby greatly enhancing local convective heat transfer. Additionally, due to the relatively small velocity gradient in the slotted regions, local resistance is effectively reduced. As a result, the proposed transverse slotted channel improves the heat transfer capability of the channel by 2.24%~2.59%, reduces the resistance by 6.66%~7.91%, and increases the overall heat transfer performance by 9.87%~11.02%.

printed circuit heat exchanger  /  entrance effect  /  transverse slotted channel  /  thermal-hydraulic performance  /  high-efficiency and low-resistance enhancement