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• Thermoelastic vibration analysis of rotational pre-twisted FGTBC-coated blades is presented. • CUF combined with 3-D elastic shell theory is used to ensure the calculation accuracy. • A separate deflection analysis is presented to capture initial mechanical-thermal stresses. • An experimental study on vibrations of different pre-twisted shell-type blades is conducted. A quasi-3D theoretical model for analyzing the thermoelastic vibrations of rotational pre-twisted, curved blades coated with functionally graded thermal barrier coatings (FGTBCs) is presented. The FGTBC-coated blades are assumed to operate within a steady-state temperature field. Three temperature distribution models, representing uniform, non-uniform symmetrical, and non-uniform asymmetrical temperature distributions, are derived by solving heat conduction equations established along the blade's thickness direction. The considered blade is theoretically simplified as a twisting shell panel, utilizing the Carrera unified formulation in conjunction with three-dimensional elastic theory to ensure the quasi-3D calculation accuracy. Rotational effects, including the mechanical-thermal prestress stiffening, rotating softening, and Coriolis force, are systematically considered. Accurate mechanical and thermal stress distribution within the FGTBC-coated blade is obtained through a separated quasi-equilibrium static analysis. By incorporating higher-order nonlinear strain terms, the mechanical and thermal prestress stiffening effect is quantified as additional potential energy and involved into the overall energy functional of the system. Thermal-elastic vibration equations of the rotational twisted FGTBC-coated blades are derived using Hamilton's principle. Experimental validations on dynamic modeling of three shell panels with different twisting angles are conducted. The proposed model's convergence and correctness are validated against reported findings, numerical simulations, and experimental test data. Finally, the study analyzes the effects of temperature load, rotation velocity, structural parameters, and material parameters on mechanical-thermal stresses and thermo-elastic vibrations of rotational pre-twisted FGTBC-coated blades. [ABSTRACT FROM AUTHOR]

In current attempt, to scrutinize the efficiency of unit, Nusselt numbers as well as skin friction factor were calculated numerically. The unit consists of two plates which rotate and magnetic field was imposed vertically. The carrier fluid is mixture of water and copper and single phase mode was selected due to low concentration. With involve of viscous dissipation impact in energy equation the final equations were obtained. After employ of similarity transformation, ordinary equations were modeled by RK4 and verification test reveals the nice accuracy. Impacts of R and Kr on Cf are in same direction and both have positive effect. The presence of magnetic field reduces the impact of R while it raises the impact of Kr. Cf rises about 1.98% with augment of R when R = 1, M = 0, Kr = 1, and φ = 0.04. Due to greater interaction of nanomaterial in higher volume fraction, the Cf declines with rise of φ and such reduction impact augments if magnetic field imposed. When M = 6, R = 1, and Kr = 1, as φ augments from 0 to 0.04, Cf declines about 6.1%. The growth of Lorentz forces can augment the Cf about 21.70% when R = 0.1, Kr = 1, and φ = 0.04. Nu reduces about 1.16% with rise of M when Kr = 6, R = 1, Ec = 0.04, and φ = 0.04. Nu has reserve relation with Ec and Kr. Both factors make the heat transfer rate to decline. Nu experiences reduction about 4.68% with rise of Ec when Kr = 6, R = 1, M = 9, and φ = 0.04. Positive impact of R on Nu reduces with rise of M. [ABSTRACT FROM AUTHOR]

Abstract Taylor–Couette–Poiseuille (TCP) flow dominates the inner water-cooling circulation of canned motor reactor coolant pumps. Current research on TCP flow focuses on torque behaviors and flow regime transitions through experiments and simulations. However, research on axial flow resistance in a large Reynolds number turbulent state is not sufficient, especially for the various flow patterns. This study is devoted to investigating the influence of annular flow on the axial flow resistance of liquid in the coaxial cylinders of the stator and rotor in canned motor reactor coolant pumps, and predicting the coolant flow distribution between the upper coil cooling loop and lower bearing lubricating loop for safe operation. The axial flow resistance, coupled with the annular rotation, is experimentally investigated at a flow rate with an axial Reynolds number, Re a, from 2.6 × 103 to 6.0 × 103 and rotational Reynolds number, Re t, from 1.6 × 104 to 4.0 × 104. It is revealed that the axial flow frictional coefficient varies against the axial flow rate in linear relation sets with logarithmic coordinates, which shift up when the flow has a higher Re t. Further examination of the axial flow resistance, with the Re a extending to 3.5 × 105 and Re t up to 1.6 × 105, by simulation shows gentle variation rates in the axial flow frictional coefficients against the Re a. The relation curves with different Ret values converge when the Re a exceeds 3.5 × 105. A prediction model for TCP flow consisting of a polygonal approximation with logarithmic coordinates is developed to estimate the axial flow resistance against different axial and rotational Reynolds numbers for the evaluation of heat and mass transfer during transition states and the engineering design of the canned motor chamber structure.

Taylor–Couette–Poiseuille (TCP) flow dominates the inner water-cooling circulation of canned motor reactor coolant pumps. Current research on TCP flow focuses on torque behaviors and flow regime transitions through experiments and simulations. However, research on axial flow resistance in a large Reynolds number turbulent state is not sufficient, especially for the various flow patterns. This study is devoted to investigating the influence of annular flow on the axial flow resistance of liquid in the coaxial cylinders of the stator and rotor in canned motor reactor coolant pumps, and predicting the coolant flow distribution between the upper coil cooling loop and lower bearing lubricating loop for safe operation. The axial flow resistance, coupled with the annular rotation, is experimentally investigated at a flow rate with an axial Reynolds number, Rea, from 2.6 × 103 to 6.0 × 103 and rotational Reynolds number, Ret, from 1.6 × 104 to 4.0 × 104. It is revealed that the axial flow frictional coefficient varies against the axial flow rate in linear relation sets with logarithmic coordinates, which shift up when the flow has a higher Ret. Further examination of the axial flow resistance, with the Rea extending to 3.5 × 105 and Ret up to 1.6 × 105, by simulation shows gentle variation rates in the axial flow frictional coefficients against the Rea. The relation curves with different Ret values converge when the Rea exceeds 3.5 × 105. A prediction model for TCP flow consisting of a polygonal approximation with logarithmic coordinates is developed to estimate the axial flow resistance against different axial and rotational Reynolds numbers for the evaluation of heat and mass transfer during transition states and the engineering design of the canned motor chamber structure. [ABSTRACT FROM AUTHOR]

This work presents a theoretical study on the effects of rotation on the nonrelativistic quantum motion of a charged particle confined to a 2D ring in the presence of the Aharonov–Bohm effect and a uniform magnetic field. We formulate the Schrödinger equation with minimal coupling, incorporating the gauge field for the rotating frame and the potential vector of the electromagnetic field. By solving the equation of motion, we determine the eigenvalues and eigenfunctions of the particle. We analyze the probability distribution as a function of varying rotating parameter values and observe a perceptible shift in the distribution. This shift indicates a higher probability of locating the electron at the edges of the ring. The second part of our study focuses on the investigation of rotation effects on the linear and nonlinear optical properties of the system. Specifically, we examine the linear, nonlinear, and total refractive index changes, as well as the optical absorption coefficients. Through numerical analysis, we demonstrate significant rotating effects on energy levels and optical properties. Our findings indicate that, for the considered physical parameters, the impact of rotation on the optical properties becomes prominent at values on the order of a few terahertz. • Description of physical properties of a 2D quantum ring. • Electron in a rotating frame. • Quantum ring in a uniform magnetic field. • Rotation effects on the optical and electronic properties of a 2D quantum ring. [ABSTRACT FROM AUTHOR]

For large-scale offshore wind turbine blades, ANSYS and UG were respectively used to complete the solid modeling and the calculation of vibration modes, and the influences of the rotating speed on each order vibration mode and their main reasons were analyzed. Furthermore, the effects of material categories, the deviations of physical parameters in the process of material manufacture and structural parameters on the natural frequencies of rotating blades were respectively compared. Numerical results show that the dynamic stiffening effect of rotating blades is obvious, and the stress stiffness and the geometric stiffness play a dominant role on the natural frequencies from the first to the sixth order and from the seventh to the tenth order respectively. The influences of material categories on natural frequencies of the blades are significantly higher than those of physical parameter deviations and chord length changes. The effects of the equal amplitude increase of elasticity modulus or the chord length and the equal amplitude decrease of density on the tenth order frequency for the torsional vibration are less than those of them on the first nine orders' frequencies for the shimmy and flapping vibration, making that the increase amplitude of the blade natural frequencies first increases and then decreases with the increase of the order number. In addition, the results in this work can provide technical references for the optimization design and the further analysis of vibration characteristics of wind turbine blades. [ABSTRACT FROM AUTHOR]

Inspired by the dynamical Casimir effect, we construct a new time evolution operator (NTEO). We study the time evolution of the coherent state (TECS) via the NTEO by the technique of integration within an ordered product (IWOP) of operators. We investigate the quantum statistical properties of it, both analytically and numerically, by evaluating its Q-function, second-order correlation function, photon-number distribution and Wigner function. Furthermore, the fidelity between the TECS and the classical coherent state is also given. It is interesting to find that smaller modulation depth can lead to more chance of sub-Poissonian statistics in some cases. It is also shown that the new time evolution operator not only has squeezing effect, but also has rotating effect. [ABSTRACT FROM AUTHOR]