Accurate Eigenvalues for Fast Trains
نویسندگان
چکیده
Vibration Analysis of Rails Excited by High-Speed Trains. This was the topic of talks by Volker Mehrmann and Christian Mehl from the Technical University of Berlin. In collaboration with the company SFE they study the resonances when rail tracks are excited by high speed trains, the goal being to reduce noise and vibrations in the trains. The new ICE trains travel across Europe at speeds as high as 300 km/h but the numerical methods used to design them are at least 30 years old. More often than not the classical finite element packages produce answers that are plain wrong, failing to deliver even a single correct digit. Volker Mehrmann and Christian Mehl showed how modern methods for linear algebra can provide answers accurate to 3 digits in single (!) precision, without a change in the finite element model. The idea is to carefully exploit structure in the eigenvalue problem.
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