In order to reduce product development cycle time, aerospace companies tend to develop various correlations integrating geometric and performance parameters. This paper covers the development of a parameterization mod...In order to reduce product development cycle time, aerospace companies tend to develop various correlations integrating geometric and performance parameters. This paper covers the development of a parameterization modeling, to be used in the preliminary design phase, for the turbine cover plate of an aero-engine. The parameterization modeling of the turbine cover plate is achieved by using commercial CAD （computer aided design） software processing in batch mode. Two main approaches are presented the outer face and the skeleton models. These models can then be integrated into an iterative process for designing optimal shapes. Both models are capable of reproducing existing cover plate with reasonable accuracy in relatively shorter time periods. However, the skeleton approach provides probably the best results in terms of flexibility and accuracy, but increases programming complexity and requires greater run times.展开更多
Wall shear stress is one of the key parameters in turbulent boundary layers,playing a pivotal role in aerodynamic optimization and fuel efficiency enhancement.Although MEMS-based direct measurement stands as the most ...Wall shear stress is one of the key parameters in turbulent boundary layers,playing a pivotal role in aerodynamic optimization and fuel efficiency enhancement.Although MEMS-based direct measurement stands as the most promising approach for wall shear stress quantification,the inherent limitations of floating sensing structures under harsh environments lead to mechanical failure,representing persistent technical barriers in practical applications.This work presents a novel MEMS sensor equipped with a protective floating cover plate,achieving high-robustness measurement through coordinated structural-process innovations.Based on the Dual Silicon-On-Insulator(DSOI)fabrication process,a protective floating configuration is developed.The critical process techniques,including deep silicon etching,wet etching of glass through vias,and silicon-glass anodic bonding synergistically establish protection for the sensing structures.The established electromechanical coupling mathematical model elucidates quantitative mapping relationships between critical structural parameters and sensing performance.Experimental characterization reveals a linear sensitivity of 28.3 mV Pa^(-1) and a resonance frequency of 2.9 kHz.In supersonic tunnel experiments at Mach 2.0,the sensor achieves unprecedented full-cycle dynamic capture from establishment through stabilization to dissipation with millisecond-level transient response characteristics.This work provides a robust,high-precision solution for aerodynamic and fluid dynamics applications,paving the way for improving energy efficiency and flow control strategies.展开更多
To achieve efficient connection and integrity in prefabricated frame structures,a novel beam-column connection between prefabricated steel-reinforced concrete(SRC)columns and cast-in-situ reinforced concrete(RC)beams ...To achieve efficient connection and integrity in prefabricated frame structures,a novel beam-column connection between prefabricated steel-reinforced concrete(SRC)columns and cast-in-situ reinforced concrete(RC)beams is proposed.Four connection specimens with varying thicknesses of connecting cover plates were designed and fabricated.Low-cycle reversed loading tests were conducted to obtain mechanical performance data,allowing for analysis of behavioral patterns,including load-displacement hysteresis curves,skeleton curves,load-carrying capacity,deformation performance,energy dissipation capacity,and stiffness degradation.Test results indicate that properly designed prefabricated connections exhibit mechanical properties comparable to those of cast-in-situ concrete connections.The hysteresis curves of the prefabricated connections are well-shaped,with nearly no reduction in load-carrying capacity and deformation performance,demonstrating excellent seismic behavior.The findings provide a theoretical basis and reference for the design of prefabricated concrete frame structures.展开更多
Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quan...Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quantities are obtained using Laplace transformation and transfer matrix approach, then influences of changes in mass and stiffness of discontinuous material and the free damping layer on the input power flow and the transmitted power flow are discussed. The conclusions provide theory basis for structural optimization design and reducing noise and vibration展开更多
文摘In order to reduce product development cycle time, aerospace companies tend to develop various correlations integrating geometric and performance parameters. This paper covers the development of a parameterization modeling, to be used in the preliminary design phase, for the turbine cover plate of an aero-engine. The parameterization modeling of the turbine cover plate is achieved by using commercial CAD （computer aided design） software processing in batch mode. Two main approaches are presented the outer face and the skeleton models. These models can then be integrated into an iterative process for designing optimal shapes. Both models are capable of reproducing existing cover plate with reasonable accuracy in relatively shorter time periods. However, the skeleton approach provides probably the best results in terms of flexibility and accuracy, but increases programming complexity and requires greater run times.
基金supported by the National Key Research and Development Program of China(Grant no.2024YFB3408804)the National Natural Science Foundation of China(Grant nos.52205602&52475571).
文摘Wall shear stress is one of the key parameters in turbulent boundary layers,playing a pivotal role in aerodynamic optimization and fuel efficiency enhancement.Although MEMS-based direct measurement stands as the most promising approach for wall shear stress quantification,the inherent limitations of floating sensing structures under harsh environments lead to mechanical failure,representing persistent technical barriers in practical applications.This work presents a novel MEMS sensor equipped with a protective floating cover plate,achieving high-robustness measurement through coordinated structural-process innovations.Based on the Dual Silicon-On-Insulator(DSOI)fabrication process,a protective floating configuration is developed.The critical process techniques,including deep silicon etching,wet etching of glass through vias,and silicon-glass anodic bonding synergistically establish protection for the sensing structures.The established electromechanical coupling mathematical model elucidates quantitative mapping relationships between critical structural parameters and sensing performance.Experimental characterization reveals a linear sensitivity of 28.3 mV Pa^(-1) and a resonance frequency of 2.9 kHz.In supersonic tunnel experiments at Mach 2.0,the sensor achieves unprecedented full-cycle dynamic capture from establishment through stabilization to dissipation with millisecond-level transient response characteristics.This work provides a robust,high-precision solution for aerodynamic and fluid dynamics applications,paving the way for improving energy efficiency and flow control strategies.
基金supported by High-level Talents Program of Hainan Basic and Applied Basic Research Program of China(520RC543)Crosswise Tasks of Enterprise Entrusted(JG-ZH-A-202411-003).
文摘To achieve efficient connection and integrity in prefabricated frame structures,a novel beam-column connection between prefabricated steel-reinforced concrete(SRC)columns and cast-in-situ reinforced concrete(RC)beams is proposed.Four connection specimens with varying thicknesses of connecting cover plates were designed and fabricated.Low-cycle reversed loading tests were conducted to obtain mechanical performance data,allowing for analysis of behavioral patterns,including load-displacement hysteresis curves,skeleton curves,load-carrying capacity,deformation performance,energy dissipation capacity,and stiffness degradation.Test results indicate that properly designed prefabricated connections exhibit mechanical properties comparable to those of cast-in-situ concrete connections.The hysteresis curves of the prefabricated connections are well-shaped,with nearly no reduction in load-carrying capacity and deformation performance,demonstrating excellent seismic behavior.The findings provide a theoretical basis and reference for the design of prefabricated concrete frame structures.
文摘Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quantities are obtained using Laplace transformation and transfer matrix approach, then influences of changes in mass and stiffness of discontinuous material and the free damping layer on the input power flow and the transmitted power flow are discussed. The conclusions provide theory basis for structural optimization design and reducing noise and vibration
