used the mathematical theory of heat transfer and numerical calculations to study ventilated brake  
Figure 1: Vertilated brake discs for high-speed trains. discs. The results showed that the faster air circulates through the internal structure of a ventilated brake disc, the higher its heat dissipation rate during braking [14]. [PERSON] et al. used CFD simulations to analyse the flow field of the internal structure of a ventilated brake disc. The results showed that the flow state of the fluid had a significant effect on the thermal performance of the brake disc [15]. [PERSON] et al. conducted numerical simulation on the temperature distribution of the battery cooling system and found that increasing the inlet water flow rate can significantly improve the heat transfer capacity of the battery [16]. To explore the influence of different parameters on heat dissipation capacity, [PERSON] et al. analysed the convective heat transfer coefficient of a brake disc. They established a relationship between the Nusser numbers, Reynolds number, and the disc-to-wheel-diameter ratio to obtain a more accurate convective heat transfer coefficient for the heat dissipation process of the brake disc [17]. [PERSON] et al. analysed the effect of varying Reynolds numbers on the thermal convection of brake discs. The brake disc temperature distribution was obtained in laminar flow and forced convection [18]. [PERSON] et al. used numerical methods to study the influence of different structural parameters of vortex tube on temperature and mass flow rate. The results showed that the increase of the number of vortex tube inlets would lead to the decrease of outlet temperature [19]. [PERSON] et al. discussed the effects of Reynolds number, temperature, nano particle volume fraction, nano particle diameter, and other parameters on convective heat transfer by using numerical methods and found that the addition of nano particles had a significant impact on the heat transfer characteristics [20]. [PERSON] et al. used the finite-element volume method to consider the influence of fins with different structures on temperature and heat transfer coefficient and found that the new type of fins enhanced the heat dissipation capacity [21]. [PERSON] et al. used the numerical analysis method to find that piercing on the fin increases the area of contact with the air, which is helpful to improve the heat dissipation performance [22]. [PERSON] et al. used different treatment methods to form different microstructures on the surface of the heat sink and found that adding thermal radiation coating is helpful to improve the surface heat dissipation problem [23]. To reduce the error of simulation results, [PERSON] et al. used first-order differential equations to predict the temperature of the brake disc and obtained the pattern of variation of convection and radiation heat dissipation from the brake disc during the cooling process [24]. [PERSON] et al. developed an engineering technology and found that the volume fraction of nano particles in conventional thermal fluid is increased, which can improve the heat transfer rate [25]. [PERSON] proposed a numerical method to simulate the subcooled jet passing through the high-temperature surface [26]. It was found that increasing the water jet velocity and decreasing the fluid temperature would increase the convective heat transfer coefficient. [PERSON] et al. proposed a heat-management system. It was found that the heat dissipation effect of this method is enhanced, and the temperature uniformity is satisfied [27]. [PERSON] et al. established a three-dimensional, consistent heat dissipation channel model with both heat conduction and fluid channels. It was found that the optimal heat dissipation parameters can improve the heat dissipation performance of electronic equipment [28]. In summary, most of the research on ventilated brake discs has focused on the process of frictional heat generation, the distribution of temperature and stress fields, and the factors affecting their heat dissipation.