This paper presents a novel method to nonlinearly investigate the dynamics of the coupled axial and torsional vibrations in the circular cross section beam of the steam turbine generator using the FFT analysis. Firstly, the coupled axial and torsional vibrations of a beam are proved by equivalent law of shearing stress and different boundary conditions. Then, a nonlinear mathematical model of t...

A mathematical model of a cracked rotor and an asymmetric rotor with two disks representing a turbine and a generator is uti­ lized to study the vibrations due to imbalance and side load. Nonlinearities typically related with a “breathing” crack are included using a Mayes steering function. Numerical simulations demonstrate how the variations of rotor parameters affect the vibration response an...

This paper presents low-profile torsional actuators applicable for mesoscale and microscale robots. The primary actuator material is thermally activated Ni–Ti shape memory alloy (SMA), which exhibits remarkably high torque density. Despite the advantages of SMAs for actuator applications—high strain, silent operation, and mechanical simplicity—the response time and energy efficiency limit overa...

the cadaver spine motion segment behavior under torsional load was evaluated with the disc intact, with partial anterior discectomy and with spacer insertion. the results of this study explain how anterior lumbar discectomy and interbody fusion (alif) affects the torsional stability of the motion segment. the pseudarthrosis rate of the anterior lumbar discectomy and interbody fusion (alif) is k...

A series of wind tunnel model tests and theoretical analyses were conducted to investigate torsion excitation, response and vibration suppression of wind-excited buildings. An aeroelastic model for pure torsion vibration was developed and the aeroelastic test results were compared with those obtained by other Wind tunnel test techniques. The comparison and practice indicated that this type of m...

A new analytical method to predict the torsional capacity and behavior of R.C multi-cell box girders strengthened with carbon fiber reinforced polymer (CFRP) sheets is presented. Modification was done on the Softened Truss Model (STM) in the proposed method; the concrete torsional problem is solved by combining the equilibrium conditions, compatibility conditions and constitutive laws of materi...

Elastomers have wide and ever increasing applications in several industries. For example, elastomeric bushings are used in automotive suspension systems to reduce amplitude of vibrations as well as shocks. In this study, a compressible visco-hyperelastic approach is employed to investigate the behavior of these bushings. Time-discrete form of the material model (Exp–Ln visco-hyperelastic model)...