동적 점착 모델을 이용한 점착계수 예측

초록

Dynamic scattered variation of the coefficient of adhesion (CoA) with the slip rate is defined in this studyas the dynamic variance. A two-dimensional (2D) dynamic CoA model was used to verify whether the 2D dynamicCoA model can accurately estimate the experimentally measured CoA and capture the dynamic variance. Qualitativeanalysis was performed to determine the parameters primarily causing the dynamic variance. To do this, the CoAs at thewheel-rail contact under dry conditions were tested using a twin-disc rig at 1,000, 1,500, and 2,000 rpm. The wheeldrivingtorque, normal contact force, and rotational speeds of wheel and rail discs were measured. The empirical coefficientsin the 2D dynamic CoA model were found using MATLAB optimization toolbox for each rotation speed. Theexperimentally measured CoAs were estimated using the 2D dynamic CoA model with the determined empirical coefficientsat each rotation speed. The results showed that the 2D dynamic CoA model can estimate the measured CoAs atall rotation speeds with good accuracy (within 7% of the percent-root-mean-square-error) and successfully capture thedynamic variance. The qualitative analysis showed that no parameters primarily influence the dynamic variance.

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