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The honeycomb sandwich structure reflector panel is a multilayer structure formed by three-layer aluminum plate and two-layer honeycomb bonded by epoxy resin adhesive, and its thermal deformation behavior is complicated. In this study, the thermal deformation behavior of the reflector panel is studied by a combination of experiment and finite element simulation. Firstly, the thermal deformation analysis finite element model of reflector panels with honeycomb sandwich structure is established. The three-layer aluminum plate is modeled according to actual geometric parameters and adopts shell element model. The honeycomb core is equivalent to a homogeneous orthotropic layer with a constant thickness. The elastic modulus of the equivalent model of the honeycomb core with adhesive are obtained through the tensile and compressive mechanical performance tests. Then, the temperature deformation experiment of the honeycomb sandwich structure panel is carried out. Combined with the experimental results and the thermal deformation simulation analysis model, the multi-island genetic algorithm is used to modify the thermal expansion coefficient of the honeycomb core layer. Finally, the thermal deformation behavior of the reflector is verified by finite element simulation and experiment. The results show that the profile error distribution caused by the panel thermal deformation has continuous symmetry. From the error distribution trend and numerical deviation, the established simulation model can be used to predict the thermal deformation of sandwich panels.

Field experiment and numerical simulation are performed on a 33 kW horizontal axis wind turbine. The distribution of pressure is gathered by disposed 191 taped pressure sensors span-ward on seven particular sections of a blade. And the parameters of experimental condition of inflow and operation condition of the wind turbine are obtained at the same time. And then, the three-dimensional Reynolds averaged incompressible Navier-Stokes equations and the RNG κ-e turbulence model are used to study the aerodynamic characteristics of the wind turbine. The numerical method is proved to be more effective by contrasting the numerical results to the field experimental data. For the calculation results of the blade pressure, the closer to the root of the blade the more consistent to the values of the experiment. A greater differential is shown at the leading edge than the trailing edge. The pressure distribution contours of the blade surface are obtained too.

The interface between the Nd2Fe14B particles and the grain boundary surrounding them in Nd-Fe-B sintered magnets was modified by diffusion Dy metal selectively through the grain boundary involving the reduction of Dy2O3 or DyF3 with CaH2 and the coercivity of them was effectively enhanced from 0.98 MA/m to 1.42 MA/m with keeping the high value of remanence. The resultant coercivity was higher than that of the magnets modified with Dy2O3 (HcJ = 1.10 MA/m) and DyF3 (HcJ = 1.24 MA/m) without using any reductant such as CaH2, respectively.

The magnetic properties of NdFeB/Tb multilayered films annealed at 773-1273K were investigated by evaluating the effect of Tb spacer layer and comparing them with those of NdFeB single layered films. The as-deposited NdFeB/Tb film with a amorphous structure was crystallized at the higher annealing temperature than 923K and Nd-rich phases were formed at 1073 K, meanwhile the coercivity increased substantially. By observations of the microstructure, Tb element was found to diffuse into the Nd-rich phases to form a Tb-enriched phase around the Nd2Fe14B primary phase particles in the multilayered films.