this study introduces the differential transform method (dtm) to analyse the free vibration response of a rotating, closed section, composite, timoshenko beam which features material coupling between flapwise bending and torsional vibrations due to ply orientation. the governing differential equations of motion are derived using hamilton’s principle and solved by applying dtm. the natural frequ...

Transient thermal field in laser surface hardening treatment of medium carbon steel was analyzed by employing both three-dimensional analytical model and finite element model. In finite element model the laser beam was considered as a moving plane heat flux to establish the temperature rise distribution in the work-piece, while in analytical model laser beam was considered as an internal heat s...

In this paper, the general governing equations of three-dimensional vibrations of an Euler-Bernoulli Beam under influences of system dynamics are derived by the Hamiltonian method. Then two fundamental cases of a cantilever beam and a rotating beam are considered. The conventional methods for vibration suppression debit to expenses and make new problems such as control spillover because they ar...

This paper investigates the bending vibration of rotating single-walled carbon nanotubes (SWCNTs) based on nonlocal theory. To this end, the rotating SWCNTs system modeled as a beam with a circular cross section and the Euler-Bernoulli beam theory (EBT) is applied with added effects such as rotary inertia, gyroscopic effect and rotor mass unbalance. Using nonlocal theory, two coupled sixth orde...

We study the maximum temperature rise induced by a rotating or dithering Gaussian laser beam on a semi-infinite body. An analytical solution is obtained by solving the transient three-dimensional heat equation in a semi-infinite domain with insulating surface. The effect of rotating or dithering frequency on maximum temperature rise is quantitatively investigated for stainless steel and carbon ...

A method based on the power series solution is proposed to solve the natural frequency of flapping vibration for the rotating inclined Euler beam with constant angular velocity. The vibration of the rotating beam is measured from the position of the corresponding steady state axial deformation. In this paper the governing equations for linear vibration of a rotating Euler beam are derived by th...

The temperature distribution due to a rotating or dithering Gaussian laser beam on a finite body is obtained numerically. The authors apply various techniques to solve the nonhomogeneous heat equation in different spatial dimensions. The authors’ approach includes the Crank-Nicolson method, the Fast Fourier Transform (FFT) method and the commercial software COMSOL. It is found that the maximum ...

A prototype thermionic electron gun for a high-brightness X-ray generator has been developed. Its extraction voltage and design current are 60 kV and 100 mA (DC), respectively. The X-ray generator aims towards a maximum brilliance of 60 kW mm(-2). The beam sizes at the rotating anticathode must therefore be within 1.0 mm x 0.1 mm and a small beam emittance is required. The fabricated electron g...

Controlling the intensity behavior of a wavefront along its axis of propagation can assist, for example, with optical manipulation, trapping, and vortex generation. A particularly interesting beam with applications in three-dimensional imaging is the rotating beam [1, 2]. A certain class of diffracting elements placed in the aperture plane of a digital camera can yield a point-spread function t...

Modelling of the radioactive ion beam (RIB) targets at TRIUMF has suggested that rotating the high energy proton beam in a circle on the face of the target may provide a greater source of radioactive ions than a static incident beam. To explore this idea a system has been configured to allow the beam of protons in the primary beamline to be steered in a circle and to permit various parameters t...