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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.

In this work, we analyse the influence of the topological defects, like a spiral dislocation in two different scenarios, firstly a non-relativistic system using the Schrödinger equation for a charged particle subject to a confining potential. Furthermore, two systems with spiral dislocation in the presence of a nonuniform radial electric field, one of them with a topology-induced cut-off point yields eigenvalues of energy which are infinitely degenerated. Besides, we study Landau levels with and without rotation effects for a point charge. Thus, in this first non-relativistic part we show that there are cases where an analog of the Ahanorov-Bohm effect exists for bound states and quantum revivals. Next, we analyse the interaction of a relativistic electron with a uniform magnetic field in spiral dislocation. As well, the behaviour of the Dirac field subject to a hard-wall potential. We also show that both rotation and the topology of the spacetime impose a restriction on the values of the radial coordinate. As results, we demonstrate through the Foldy-Wouthuysen approximation that the non-relativistic limits of these situations are consistent with the solutions obtained in the first part of the thesis. Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq Neste trabalho, analisamos a influência do defeito topológico de deslocação em espiral em dois diferentes cenários, em primeiro lugar um sistema não-relativístico utilizando as equações de Schrödinger para uma partícula com carga na presença de um potencial do tipo Hard-Wall. Além disso, dois sistemas com deslocação em espiral na presença de um campo elétrico radial não uniforme, sendo um deles com um ponto de corte induzido pela topologia que produz autovalores de energia infinitamente degenerados. Assim como também, estudamos os níveis de Landau com e sem efeitos de rotação para uma carga pontual. Dessa forma, nessa primeira parte não-relativística mostramos que há casos em que existem análogos ao efeito Aharonov-Bohm para estados ligados e quantum revivals. Em seguida, investigamos a interação de um elétron relativístico com um campo magnético uniforme no espaço-tempo de deslocação em espiral. Bem como, o comportamento do campo de Dirac sujeito a um potencial do tipo hard-wall. Mostramos também, que tanto a rotação quanto a topologia do espaço-tempo impõem restrições aos valores da coordenada radial. Como resultados, demonstramos através da aproximação de Foldy-Wouthuysen que o limite não-relativístico dessas situações são consistentes com as soluções obtidas na primeira parte da tese.

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.