This study investigated the influence of casing profiles on the aeroelastic stability of a transonic compressor rotor.To elucidate the influence of casing profiles on aerodynamic damping(AD)and delve into more detaile...This study investigated the influence of casing profiles on the aeroelastic stability of a transonic compressor rotor.To elucidate the influence of casing profiles on aerodynamic damping(AD)and delve into more detailed insights,the influence coefficient method and phase-shift theory were incorporated into the conventional energy method to establish the multi-passage energy method.The unsteady pressure was calculated using the influence coef-ficient method and the outcomes at various nodal diameters(NDs)were reconstructed based on the phase-shift theory.Thus,the multi-passage energy method offers more comprehensive information than the conventional energy method,the aeroelastic eigenvalue method,and the coupled fluid-structure interaction method.Four casing profiles were simulated.In contrast to the straight casing configuration,the concave shrinking casing was found to be detrimental to aeroelastic stability.The convex shrinking casing can alleviate the blockage in the tip flow field and improve both the aerodynamic performance and aeroelastic stability.The multi-passage energy method further revealed that the AD is contributed by the blade itself and the adjacent blades.In comparison to the straight casing,the convex shrinking casing not only enhances the AD of the blade itself but also diminishes the AD fluctuation of the adjacent blades.Consequently,the minimum AD is increased.展开更多
This work is an improvement of the theory proposed by Qin Guogang and C. T. Sah for determination of deep level profiles in the multi-level ease. The previous theory cannot be applied to the ease when a level whose de...This work is an improvement of the theory proposed by Qin Guogang and C. T. Sah for determination of deep level profiles in the multi-level ease. The previous theory cannot be applied to the ease when a level whose density is comparable to the carrier density exists between the Fermi level and the deep level under study or when the deep level under study locates near the middle of the forbidden gap. The present work has overcome those restrictions so that it is applicable to more general cases. For the proton-implanted CZ-Si sample, the density profile of E(0.22), second acceptor level of divacancies, has been calculated in the presence of highly concentrated oxygen-vacancy level E(0.15) and has been compared with the profile of the same level E(0.22) calculated without considering the existence of E(0.15).展开更多
Objective This study was mainly focused on study of the proteome profile change between exposure to 1-Bromopropane(1-BP)and 1-BP poisoning.Methods The samples of serums from exposure to 1-BP and 1-BP poisoning were co...Objective This study was mainly focused on study of the proteome profile change between exposure to 1-Bromopropane(1-BP)and 1-BP poisoning.Methods The samples of serums from exposure to 1-BP and 1-BP poisoning were collected and analyzed through Label展开更多
基金supported by the National Nature Science Foundation of China(Grant No.52306034).
文摘This study investigated the influence of casing profiles on the aeroelastic stability of a transonic compressor rotor.To elucidate the influence of casing profiles on aerodynamic damping(AD)and delve into more detailed insights,the influence coefficient method and phase-shift theory were incorporated into the conventional energy method to establish the multi-passage energy method.The unsteady pressure was calculated using the influence coef-ficient method and the outcomes at various nodal diameters(NDs)were reconstructed based on the phase-shift theory.Thus,the multi-passage energy method offers more comprehensive information than the conventional energy method,the aeroelastic eigenvalue method,and the coupled fluid-structure interaction method.Four casing profiles were simulated.In contrast to the straight casing configuration,the concave shrinking casing was found to be detrimental to aeroelastic stability.The convex shrinking casing can alleviate the blockage in the tip flow field and improve both the aerodynamic performance and aeroelastic stability.The multi-passage energy method further revealed that the AD is contributed by the blade itself and the adjacent blades.In comparison to the straight casing,the convex shrinking casing not only enhances the AD of the blade itself but also diminishes the AD fluctuation of the adjacent blades.Consequently,the minimum AD is increased.
基金The project supported by the National Natural Science Foundation of China.
文摘This work is an improvement of the theory proposed by Qin Guogang and C. T. Sah for determination of deep level profiles in the multi-level ease. The previous theory cannot be applied to the ease when a level whose density is comparable to the carrier density exists between the Fermi level and the deep level under study or when the deep level under study locates near the middle of the forbidden gap. The present work has overcome those restrictions so that it is applicable to more general cases. For the proton-implanted CZ-Si sample, the density profile of E(0.22), second acceptor level of divacancies, has been calculated in the presence of highly concentrated oxygen-vacancy level E(0.15) and has been compared with the profile of the same level E(0.22) calculated without considering the existence of E(0.15).
文摘Objective This study was mainly focused on study of the proteome profile change between exposure to 1-Bromopropane(1-BP)and 1-BP poisoning.Methods The samples of serums from exposure to 1-BP and 1-BP poisoning were collected and analyzed through Label
