Experimental and numerical simulation of the effect of free particles dispersed within microchannels on pool boiling heat transfer

•We have obtained a new heat transfer surface with composite structure, is applied to pool boiling experiment, with very good heat transfer capability.•Compared to a polished surface, this surface can increase CHF by 192%, increase HTC by 333%, and reduce ONB by 86%.•A high-speed camera was used to film the pool boiling process with the movement of the bubbles observed.•A computer was used to simulate and calculate the physical model, which has the same dimensions and surface structure as the actual sample, after the simulated calculations the same conclusion as the experiment was drawn. Pool boiling represents an efficient method of heat transfer. In this experiment, porous media with microchannels are prepared using the high-temperature sintering method for copper powder. The investigation focuses on the impact of various proportions of free particles dispersed within the microchannels on the heat transfer performance during deionized water pool boiling. The microchannels within the porous media maintain consistent width and depth. The findings reveal enhancements in critical heat flux (CHF) and heat transfer coefficient (HTC). Notably, the heat transfer surface featuring 20 % free particles dispersed within the microchannels (FPPM-20 %) exhibits the most significant strengthening effect. This is evidenced by a reduction of ΔT by 5 °C, an increase in CHF by 192 %, and an increase in HTC by 333 % compared to the polished copper surface. The physical model with the same structure is simulated using ANSYS, yielding results consistent with the experimental findings.