Regulation mechanism of bionic wireless power device thermal management system based on nanofluids and magnetic field

Thickness of thermal boundary layer on surfaces with different wavy frequencies. [Display omitted] •Disordered temperature jumps under magnetic field excitation is studied.•Heat transfer mechanisms near the wall of the tunnel are analyzed.•Thermal boundary layer changes under magnetic field excitation is studied.•Heat transfer characteristic is improved by 41.59% under magnetic field. For further optimal power conservation and dissipation performance of wireless power devices, this paper presented a cooling system that couples a wave bionic surface structure with composite magnetic nanofluids. Heat transfer mechanisms near the wall of the channel under magnetic field excitation have been developed. Effect of changes in the near-wall thermal boundary layer on the integral heat transfer was analyzed, and a comprehensive evaluation of the model performance was given. The outcomes revealed that as the flow approaches the crest, the difference in thermal boundary layer thickness for different flow Reynolds numbers becomes small, and in the flow region in the second half of the wave crest, the thermal boundary depth is no longer regular at different Reynolds numbers, which is due to the “detached flow”. “Detached flow” effectively breaks the thermal boundary enhancing the heat transfer performance. Temperatures excited by magnetic forces show disordered “jumps”, and the heat transfer characteristics are substantially improved by 41.59 % under magnetic field. Comprehensive evaluation index under magnetic field excitation is up to 1.54 for wave bionic surfaces with a frequency of 20 rad/s.