Squealing of railway block brakes. Preliminary investigations on operational squealing frequencies, shapes and design of a test rig.

• Applicants: Professor Dr.-Ing. Markus Hecht; Professor Dr.-Ing. Utz von Wagner
• Subject Area: Mechanics
• Term: from 2014 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 260168618

Block brakes have been used for railway vehicles since the early beginnings about 200 years ago. In the last decades, block brakes at passenger cars have widely been replaced by disk brakes. The advantages of the disk brakes are higher brake forces and the lack of roughening of the wheel tread. Disk brakes are also known for having a lower tendency to squeal. Compared to disk brakes, block brakes are simpler, cheaper, space saving and light. These properties make block brakes indispensable at least for millions of freight cars. Nevertheless noise is one of the essential problems of today¿s railway traffic and block brakes are well known for their tendency to ear-deafening squeal. The aim of the project is to investigate railway block brakes for their noise behavior with special interest on squeal. In a first step, an operational modal analysis is performed at freight wagons. Based on this this, modifications of an existing block brake test rig are designed. This test rig should enable in a second step to perform extensive experimental investigations of the phenomenon of squeal together with a corresponding modeling.

• DFG Programme: Research Grants