Figure 4
The image contains four panels, each with multiple line graphs. Panel A shows creep velocity curves of each axle with four line graphs. The x-axis represents time in seconds, and the y-axis represents creep velocity in meters per second. Each line graph is color-coded: red for the first axle, blue for the second axle, black for the third axle, and green for the fourth axle. Panel B shows the variation of adhesion coefficient with four line graphs. The x-axis represents time in seconds, and the y-axis represents the adhesion coefficient. Each line graph is color-coded similarly to Panel A. Panel C shows the motor output torque of each axle with four line graphs. The x-axis represents time in seconds, and the y-axis represents motor output torque in Newton meters. Each line graph is color-coded similarly to Panel A. Panel D shows axle load variation with four line graphs. The x-axis represents time in seconds, and the y-axis represents axle load in Newtons. Simulation results of Case 2: alternating dry and wet rail surface conditions. Source: Authors’ own work