Research on numerical method for non-hertzian contact problem between wheel and rail (2nd report, an effective way for evaluating the analyzed area and its application to contact problems between Wheel and Rail)

In this paper, we present the result of a study made on an effective numerical method for evaluating the area, which has to be analyzed to find a contact area precisely. The contact area is found as an area where normal contact pressure is plus in the analyzed area when one solves a normal contact problem applying Kalker's "EXACT THEORY". Therefore, it is inferable that one can find a contact area and contact pressure finely within a limited amount of analyzed points if the analyzed area can be set slightly larger than the true contact area. It is allegeable in this paper that applying our proposed method one can find a better analyzing area minifying the former analyzed area in the process of an optimal calculation and can find a precise contact area, pressure distribution, etc. in the end of the calculation. First, the algorithm of reducing the analyzed area is stated and applied to the normal contact problem of two balls. Then, it is applied to contact problems of wheel and rail. The algorithm works satisfactorily, and the results revealed a good coincidence with the results calculated by the Kalker's original algorithm. The iteration counts of our method where the analyzed area is set approximately 10 to 100 times as large as the true contact area is less than two times that of Kalker's where the analyzed area is purposely set slightly larger than the true contact area.