Papers by Keyword: Poisson Ratio

Abstract: Fluid-solid coupling numerical method of propellers is applied to make numerical calculations of propellers made of different materials without considering the material anisotropic. Comparative analysis of hydrodynamic performance and wake flow field of the propellers are carried on under typical working conditions. The influence of the key parameters of material on the efficiency of marine propellers is analyzed. The results show that the material with greater elasticity makes the magnitude of speed increase,especiously the axial velocity. On the other hand, compared with the strong rigidity material propeller, the small rigidity material propeller increases a little in the highest value of propeller efficiency curve.

Abstract: The same batch reactive powder concrete specimens were obtained with same raw materials and curing process, uniaxial compressive strength test had been done on the specimens after hot water curing placed in laboratory for seven days , three months and three years. The test results showed that seven-day strength and three-month strength of plain reactive powder concrete after hot water curing are almost equal. Strength of plain reactive powder concrete has not degradation within three months after hot water curing. While strength of plain reactive powder appears serious degradation phenomenon after placed in Laboratory for three years. Comparing uniaxial compressive strength test results of plain reactive powder concrete at three-month with three-year after hot water curing ,we find that strength of plain reactive concrete at three-year decrease about 27 percent than the strength of plain reactive powder concrete placed at laboratory for three months, and elasticity modulus increases about 71 percent, axial peak strain decrease about 62 percent respectively .With the passage of time, plain reactive powder concrete appears more Brittle Features and less toughness.

Abstract: Through the conventional triaxial test about plain reactive powder concrete under different confining pressures at 0Mpa, 25 Mpa,50 Mpa and 75 Mpa, this paper obtained the stress-strain curves in axial direction and radial direction of plain reactive powder concrete under different confining pressures, compared and analyzed the effects of confining pressures on peak strength, peak strain, Elastic modulus, Poisson ratio and failure modes of plain reactive power concrete also. The results showed that peak strength increases with the increase of confining pressure, when confining pressure increases from 0Mpa to 25Mpa, the peak strength increases most rapidly. The results also showed that peak strain increases linearly with the increase of confining pressure, when confining pressure increase from 0Mpa to 75Mpa gradually, the peak strain increases from 0.2 percent to 0.93 percent, meanwhile Poisson ratio increase with the increase of confining pressures, yet Elastic modulus changes slight at different confining pressures, failure modes of plain reactive powder concrete at different confining pressures exhibit different modes, when confining pressure is 0Mpa, failure mode presents as splitting failure, shear failure mode at 25Mpa, while shear failure merge local crushing at 50MPa and 75MPa.