1st ICAI 2020

International Conference on Automotive Industry 2020

Mladá Boleslav, Czech Republic

Table 1: Parameters and their levels of used in the two level full factorial experiment Parameter Low (-1) High (1) Speed 500 rpm 3000 rpm Load 2 kN 10 kN Viscosity 10 cSt 100 cSt Source: Own elaboration (2020) 2.3 Analysis of data from experiments Data from experiments were analysed by statistical methods. The DOE data were analysed by mean value of the signal. The ramp-ups then by minimum and maximum value of the signal and statistical variance normalised by mean value. The selection of these signal features was based on preliminary testing phase. 3. Results and Discussion Figure 3 shows curves of operating lubrication regimes predicted by model of bearing and EHL film. It indicates that with low viscosity oil, fully developed EHL regime cannot be achieved within range of tested speeds. On the other hand, high viscosity oil – 100 cSt allows operate bearings in EHL regimes from speeds 750 rpm (under theoretical isothermal condition). With 46 cSt oil the transition to EHL mode would occur at speed around 1600 rpm. Figure 3: Predicted values of Tallian’s lubrication λ -parameter for 3 oil viscosities at bearing load corresponding 5 kN, obtained from mathematical models

Source: Own elaboration (2020) Results from experiments are depicted in Figures 4 and 5. Figure 4, obtained by processing data from DOE, shows that the mean value of the propagation time increases by in average 36 ns when the speed is increased from 500 rpm to 3000 rpm,

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