Our new work has demonstrated that the bulk airflow within the ventilated channel of a rotating brake disc with pin-fins at realistic rotation speeds for braking (i.e., from 100rpm to 300rpm) follows a predominantly backwards sweeping inline-like path between the pin-fins. Internal local heat transfer is distributed non-uniformly on both inboard and outboard surfaces, with twice higher average cooling from the outboard surface than the inboard surface: this possibly exacerbates the thermal stresses, which leads to thermal distortion of the rotor (i.e., coning).
(Temperature distributions on ventilated channel surfaces of a “rotating” pin-fin brake disc mapped by thermochromic liquid crystal)
This work has been published as M.D. Atkins, F.W. Kienhöfer, T.J. Lu, T. Kim (2020), “Local heat transfer distributions within a rotating pin-finned brake disc” in the ASME Journal of Heat Transfer (https://doi.org/10.1115/1.4047836) as a result of international collaboration between MLMS at NUAA, China and University of the Witwatersrand, South Africa.
