Railway Wheel Squeal (Squeal of Disk Subjected to Periodic Excitation)

As a fundamental study of the squeal of a railway wheel running on a corrugated rail, frictional experiments using a thin steel disk and a rod and analysis were performed. A disk representing the railway wheel was clamped at the center with a free periphery and subjected to periodic excitation in its axial direction. When the frequency of excitation is not close to any natural frequency of the disk, squeals with a single nodal diameter mode occur. Squeals at the natural frequency of the disk fall into resonance with the frequency of the excitation, provided that the two frequencies are the same. Then two kinds of squeals occur: squeal at entrained frequency and that at both the entrained frequency and the frequency of another vibrational mode of the disk.