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A unified formulation of finite prism methods (FPMs) based on Reissner's mixed variational theorem is developed for the three-dimensional (3D) free vibration analysis of functionally graded (FG) carbon nanotube-reinforced composite (CNTRC) plates and laminated fiber-reinforced composite (FRC) plates, the edge conditions of which are considered such that one pair of opposite edges is simply supported and the other pair may be combinations of free, clamped or simply supported edges. The single-walled carbon nanotubes (CNTs) and polymer are regarded as the reinforcements and matrices, respectively, to produce the CNTRC plate. Four different distributions of CNTs varying in the thickness direction are considered (i.e. the uniformly distributed, and FG V-, rhombus-, and X-type variations), and the throughthickness distributions of effective material properties of the CNTRC plate are determined using the rule of mixtures. In the formulation, the CNTRC/FRC plate is divided into a number of finite prisms in the x À domain, in which the trigonometric functions and Lagrange polynomials are used to interpolate the y-direction and x À plane variations for the primary variables of each individual prism, respectively, and the related orders used for expansion of assorted primary variables in the thickness coordinate can be freely chosen. It is shown that the eight-and nine-node quadratic FPM solutions of frequency parameters of simply supported, CNTRC plates and laminated FRC plates are in excellent agreement with the exact 3D solutions available in the literature, and with the ones obtained using the ANSYS software for those plates with various boundary conditions.

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A high-speed miniature pump is proposed for the application in aerospace area, where high efficiency and reliability are expected for the pump under the microgravity operation condition. In this paper, a miniature centrifugal pump with dynamic bearing is selected as the objective for the performance development. The prototype of the miniature pump is manufactured and tested by experiments at the rotational speed of 10,000r/min. The comparison of hydraulic performance near the design operation shows good agreement between the numerical results and experimental data. In order to improve hydraulic performance of the pump, the effects of splitter blades, number of blades, and wrap angle of blades are analyzed numerically. For each operating condition, in order to compare the influence of splitter blades on the performance and the internal flow, the impellers with and without splitter blades are designed respectively. In addition, for the splitter blades, the influence of the splitter blade position and the splitter blade thickness are also investigated. The numerical result shows that the highest efficiency among all the impellers is achieved with the blade number of 5, wrap angle of 160° and with no splitter blades. Moreover, for the impellers with the splitter blades, hydraulic performance of the pump is mainly decided by the main blades, while the splitter blades hardly help to improve the efficiency of the pump. The study is helpful for the further application of the high-speed miniature pump in various societies.

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