Study On Vibration Characteristics Of Casing Connecting Structure Based On Finite Element Model Validation Technology

Bolt connection structure is widely used in a variety of mechanical connection structure,but also for aircraft engine parts, in particular the engine stator casing in the most commonlyused as a fastening connection mode. On the motor stator casing for finite element analysis ofthe dynamic characteristics, will encounter a lot of bolt connection structure, if we considerthe influence of bolt connection, making the calculation scale is huge, and it is difficult toaccurately simulate the bolt connection structure for casing structure, and the computingrequirements are also higher, so the domestic and foreign research this problem when thegeneral neglect of bolt connection for the engine casing ’s dynamic characteristics, but in theactual engine casing structure of bolt connection number and is particularly much, if weignore the influence on dynamic characteristics, the results will appear bigger error.Especially in the bolt connecting structure of loosening or casing structure vibration is larger,often accompanied by a bolt connecting structure of local strong nonlinear generation, on thecasing parts of the kinetic characteristics of impact will be more serious. This paper focuseson the study of the handguard simplified model of bolt connection on casing dynamic impacttest and finite element calculation, from two aspects of bolted flange connections on casingdynamic effects, emphasis is bolted flange connection local nonlinear characteristics oncasing modal effects. The machine box bolt flange connection structure for tightening torque0N M40N M,20N, M,60N M four groups of fixed frequency and sweep frequency test,each have a1.7G,2.7G,3.7G three groups of constant acceleration vibration force amplitudetest. From the test of bolt connection structure of the local nonlinear characteristics on casingmodal effects, is established using finite element software the test machine casing finiteelement model and carried out under the same test condition analysis. The calculation and theanalysis show that considering the bolt connection structure calculation model is better thansimple treatment into a whole rigidity calculation model analysis result to be accurate formany. In this paper, the design and calculation of casing has certain reference function.