## 2 Materials and Methods
### Experimental Verification
Table 2 presents a comparison of the experimental data with the simulation results. The first column lists the centrifugal acceleration values, and the second column presents the experimentally determined motor power. The third column represents the windage power derived from the simulations, while the fourth column gives the deviation value, which reflects the difference between the simulated windage power and the actual motor power as measured in the experiments. Notably, the deviation values illustrated in Figure 6 were derived from the experimental motor power via a fitted curve, which is distinct from the deviation definition used in the fourth column of Table 2. The calculation of the actual windage power requires subtracting both the motor efficiency loss and bearing friction loss from the measured motor power. A brief discussion regarding the estimation of these two types of losses follows. According to data provided by the motor manufacturer, the efficiency of the ZJU400 motor was approximately 90%. A direct measurement of the bearing friction power on the ZJU400 experimental platform is currently quite challenging. Thus, estimations were made based on two assumptions:  
Figure 6: Comparison of the measured motor power and computational fluid dynamics (CFD) simulated windage loss. As the deviation values of the simulated windage power and motor power in Table 2 consistently lie within the range of \(-28.7\%\) to \(-7.8\%\), hypothesis 1 is thereby supported as being reasonable. Hypothesis 2 pertains to the calculation method for bearing friction power loss proposed by [PERSON] et al. (2018). Based on this method, we deduce that the potential range for bearing friction power under an acceleration of 10 g might extend from 0 to 1.95 kW (bearing friction loss power = measured motor power \(\times\) motor efficiency \(-\) simulated windage power/(from 0.7 to 1.15)). Subsequently, by leveraging the established exponential relationship of the 1.5 th power between the bearing friction loss power and the angular velocity, we estimated the probable range for the bearing friction loss power, which is presented in the fifth column of Table 2. The sixth column in Table 2 presents the error between the simulated windage power and corrected power (where the corrected power refers to the measured actual motor power after deducting both the motor efficiency and bearing friction losses). After considering both the motor efficiency and bearing friction losses, the positive deviation in the simulated windage power clearly does not exceed 15%. At an acceleration of 10 g, the maximum negative deviation reaches \(-20.7\%\). Note that the actual error is expected to be less than \(-20.7\%\) owing to the inherent uncertainty in estimating the bearing friction loss. For instance, at 10 g, assuming that the potential range of the bearing friction power lies between 0 and 1.95 kW, the maximum error of \(-20.7\%\) would only occur if the friction loss was assumed to be 0, which is clearly unrealistic because friction loss cannot be zero in practice. The error decreases with increasing angular velocity, reaching a maximum range of \(-15\%\) to \(12.2\%\) when the gravitational acceleration exceeds 60 g (Table 2). This is because bearing friction loss increases proportionally with angular velocity raised to the power of 1.5, whereas windage loss, according to Equation (13), increases proportionally with the angular velocity raised to the power of 3.11. As the angular velocity increases, the proportion of bearing friction loss in the total loss diminishes, thereby reducing the influence of the estimation uncertainty associated with friction loss on the overall error. Consequently, the \(-15\%\) to \(12.2\%\) error for gravitational accelerations greater than 60 g more accurately reflects the precision of the simulation. The close match between the simulated windage power values and experimental data strongly confirm the accuracy of the simulation results.