学術雑誌論文

大型送風機用羽根車の微小亀裂原因調査と構造変更(機械力学,計測,自動制御)

An Investigation of the Small Crack and Structural Modification for a Big Impeller(Mechanical Systems)

jpn

03875024

社団法人日本機械学会

日本機械学會論文集. C編

729

1321

1328

2007-05-25

Version of Record

[No.06-0967]

The crack arose during actual operation, in an impeller of large-sized blower, at the joint part of the main board and blade. For the purpose to clarify this phenomenon, dynamic analysis and static analysis using the finite element method were performed. The analysis results showed that the cause of a crack of impeller is the stress which occurs owing to the deformation of the side board by centrifugal force. This deformation is wave like one which is same pitch as blade. Then, the structural modification by pseudo-inverse method was performed for the purpose of stress reduction. In this case, designer does not want the minimum weight optimum design but the minimum modification design. Pseudo-inverse method may modify the structure with the minimum distance in the design variable space to satisfy the stress restriction. Some cases are tried. When the design variables were 3 main parts thicknesses, those are main board, side board and blade, practical solution is deduced for 8 calculations to satisfy the stress limit with 10% weight increase. 収録刊行物

Article

AN00187463