In mechanics mistuning is a lack of symmetry present in a real object that ideally is perfectly symmetric. This phenomenon is studied for example in the turbine disks; it can cause an increase of the forced response that can bring to unexpected failures due to fatigue. Mistuning is caused by manufacturer tolerances, non homogeneity of the material, the usage, etc., and so it is unavoidable. It has been observed that the amount of increase in the forced response of mistuned turbine disks strongly depends on the physical characteristics of the disk itself: actual efforts to limit the negative effects of this phenomenon into turbine disks are to understand how to design a disk that is not much influenced by mistuning in the working rotational speed.
US Patent Issued to Rolls-Royce Deutschland on Sept. 20 for "Method for Determining Blade Mistuning on Integrally Manufactured Rotor Wheels" (German Inventors)
Sep 26, 2011; ALEXANDRIA, Va., Sept. 26 -- United States Patent no. 8,024,137, issued on Sept. 20, was assigned to Rolls-Royce Deutschland Ltd...