Estimate of the effect of certain properties of a composite material on the dynamic characteristics of cylindrical shells

1979 ◽  
Vol 15 (6) ◽  
pp. 547-550
Author(s):  
V. I. Kuptsov
Keyword(s):  
Composite Material ◽  
Dynamic Characteristics ◽  
Cylindrical Shells

Dynamic analysis of a helical geared rotor-bearing system with composite rotating shafts

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ying-Chung Chen ◽  
Xu Feng Cheng ◽  
Siu-Tong Choi
Keyword(s):  
Composite Material ◽  
Dynamic Analysis ◽  
Dynamic Characteristics ◽  
Mesh Stiffness ◽  
Content Type ◽  
Gear Mesh ◽  
Rotor Bearing ◽  
Rotating Shafts ◽  
Gear Mesh Stiffness ◽  
Bearing System

Purpose This study aims to study the dynamic characteristics of a helical geared rotor-bearing system with composite material rotating shafts. Design/methodology/approach A finite element model of a helical geared rotor-bearing system with composite material rotating shafts is developed, in which the rotating shafts of the system are composed of composite material and modeled as Timoshenko beam; a rigid mass is used to represent the gear and their gyroscopic effect is taken into account; bearings are modeled as linear spring-damper; and the equations of motion are obtained by applying Lagrange’s equation. Natural frequencies, mode description, lateral responses, axial responses, lamination angles, lamination numbers, gear mesh stiffness and bearing damping coefficients are investigated. Findings The desired mechanical properties could be constructed using different lamination numbers and fiber included angles by composite rotating shafts. The frequency of the lateral module decreases as the included angle of the fibers and the principal shaft of the composite material rotating shaft increase. Because of the gear mesh stiffness increase, the resonance frequency of the coupling module of the system decreases, the lateral module is not influenced and the steady-state response decreases. The amplitude of the steady-state lateral and axial responses gradually decreases as the bearing damping coefficient increases. Practical implications The model of a helical geared rotor-bearing system with composite material rotating shafts is established in this paper. The dynamic characteristics of a helical geared rotor-bearing system with composite rotating shafts are investigated. The numerical results of this study can be used as a reference for subsequent personnel research. Originality/value The dynamic characteristics of the geared rotor-bearing system had been reported in some literature. However, the dynamic analysis of a helical geared rotor-bearing system with composite material rotating shafts is still rarely investigated. This paper shows some novel results of lateral and axial response results obtained by different lamination angles and different lamination numbers. In the future, it makes valuable contributions for further development of dynamic analysis of a helical geared rotor-bearing system with composite material rotating shafts.

Stability analysis in wound composite material axial impeller

2011 ◽  
Vol 226 (5) ◽  
pp. 1162-1172 ◽  
Author(s):  
J Wang ◽  
J Piechna ◽  
J A O Yume ◽  
N Müller
Keyword(s):  
Composite Material ◽  
Stability Analysis ◽  
Dynamic Characteristics ◽  
Composite Laminates ◽  
High Performance ◽  
Low Cost ◽  
Modal Shape ◽  
Element Analysis ◽  
Rotating Speed ◽  
Wound Composite

A stability analysis is developed to assess the stresses and dynamic characteristics of the wound composite material axial impeller under centrifugal force loading conditions. This procedure is based on finite element analysis (commercial software ABAQUS) results. A low-cost, light-weight, high-performance composite turbomachinery impeller with a uniquely designed blade patterns is evaluated. Understanding the stress–strain behaviour of fibre-reinforced composite laminates as it relates to ultimate failure and the ability to predict ultimate strength is critical in the design of safe and lightweight impellers. To determine failures, the maximum stress failure criterion is used. In order to avoid operating at resonance, which can make impellers suffer a significant reduction in the design life, the designer must calculate the natural frequency and modal shape of the impeller to analyse the dynamic characteristics. The results show that using composite Kevlar fibre/epoxy matrix enables the impeller to run at a rotating speed 2228 rad/s and withstand the stresses, no critical speed will be matched during start-up and shut-down, and that mass imbalances of the impeller shall not pose a critical problem.

Sign in / Sign up

Export Citation Format

Share Document