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The tip vortex cavitation (TVC) is an issue of increasing interest, because the TVC plays an important role in propeller radiated noise and cavitation erosion. The marine propeller with winglets, which is inspired by the winglets of airfoil, is numerically investigated in the present paper. The blade tip of newly designed propeller tilts toward the pressure side. The difference between six propellers is the change of the rake angle at r/R = 1.0. The pressure coefficient, TVC, axial velocity field and helicity are analyzed. The numerical results show that the winglets of newly designed propeller scarcely affect the efficiency of propeller. The thrust coefficient gradually decreases with the increase in rake angle. As for the suction side, the pressure coefficient (Cp) of winglets propellers is higher than the conventional propeller in general. In addition, the winglets are beneficial to generate less cavitation behavior when the rake angle is small. However, as the rake angle is further increased, the cavitation behavior of winglets propeller is also increased, even larger than the conventional propeller. Therefore, it can be deduced that the winglets can be used to effectively improve the TVC characteristics to some extent.

ZnO:Tb nanoparticles are prepared by a solvothermal method with the diameter of approximately 18–100 nm. At appropriate doping concentration, the lattice expansion occurs. With the increase in the doping ratio of Tb/Zn from 0 to 0.03, ZnO lattice first contracts slightly, then expands, and finally, contracts again. Tb3+ element is found to enter the ZnO lattice and replace Zn2+. Some crystal defects are generated in the host lattice for doped samples such as Zni and VO. By carefully examining the excitation and emission spectra, both VO and Zni are found to be involved in the energy transfer process. This is different from ZnO:Eu for which negative charge Oi defects are identified to play an important medium of energy transfer from ZnO host to Eu3+. It also supports another charge compensation mechanism. The energy transfer mechanism helps to theoretically explain and promote strong green luminescence of Tb3+ and improves the luminescence intensity of the RE-doped ZnO nanomaterial. It is very valuable for potential applications in bioimaging, photoluminescence, optoelectronics, and photocatalysis.