The mechanical/thermal/electrical properties on-demand design of CNTs-reinforced nanocomposites is a key scientific issue that limits the development of new-generation smart nanomaterials, and the establishment of a corresponding unified theoretical prediction model for the mechanical/thermal/electrical properties is the foundation of nanocomposites. Based on the equivalent medium theory (EMT) obtained by Maxwell far-field matching, a unified mechanical/thermal/electrical modified EMT model is established by introducing Young’s modulus, thermal conductivity, and electrical conductivity to the thin filler–matrix’s interlayer. According to literature, the proposed model was employed to theoretically calculate the variations in the overall Young’s modulus, thermal conductivity, and electrical conductivity of CNTs-reinforced nanocomposites with respect to the volume concentration of CNT fillers. Then, the applicability of the proposed theoretical model was validated in comparison with the experimental measurements. Numerical calculations showed that the interface is a key factor affecting the mechanical/thermal/electrical properties of CNTs-reinforced nanocomposites, and strengthening the interfacial effect is an effective way to enhance the overall properties of nanocomposites. In addition, the aspect ratio of CNT fillers also significantly affects the material properties of the CNT fillers interface phase and the CNTs-reinforced nanocomposites. By fitting the experimental data, the calculation expressions of the aspect ratios of CNT fillers on the Young’s modulus, thermal conductivity, and electrical conductivity of the CNT fillers interfacial phase are quantitatively given, respectively.

The vortex-induced vibration characteristics of transmission conductors under wind fields constitute a critical factor influencing structural safety. This study establishes a three-dimensional fluid–structure interaction numerical model based on the large eddy simulation method, systematically investigating the two-degree-of-freedom vibration characteristics of transmission conductors in pulsating wind fields. The vibration process evolves through four distinct stages: initial small-amplitude steady state, frequency-locked large-amplitude state, transitional modulation phase, and ultimately nonlinear chaotic stage under high wind speeds. The research reveals that within specific parameter ranges of reduced wind speed (4 < Ur< 5) and transverse displacement amplitude ratio (0.7 <Ay< 1) identified as the transition zone of vortex wake modes, the wake flow exhibits unique unsteady characteristics. This transition in vortex shedding patterns triggers significant fluid–structure interaction effects, resulting in substantial enhancement of alongwind displacement. Analysis of aerodynamic work shows that drag force performs predominantly positive work during lock-in and nonlinear stages, sustaining streamwise motion, while lift force does negative work at crosswind peaks, limiting lateral excursions. These findings clarify the multi-stage evolution of vortex-induced vibration, elucidate the wake-driven mechanism of high-amplitude vibration, and quantify the complementary roles of shear-layer instability and phase-dependent lift/drag work in governing conductor dynamics.

The primary resonance responses of high-performance nanocomposite materials used in spacecraft components in complex electromagnetic field environments were investigated. Simultaneously considering the interfacial effect, agglomeration effect, and percolation threshold, a theoretical model that can predict Young’s modulus and electrical conductivity of graphene nanocomposites is developed by the effective medium theory (EMT), shear lag theory, and the Mori-Tanaka method. The magnetoelastic vibration equation for an axially moving graphene nanocomposite current-carrying beam was derived via the Hamilton principle. The amplitude-frequency response equations were obtained for different external loading conditions. The study reveals the significant role of graphene concentration, external force, and magnetic field on the system’s primary resonance, highlighting how electromagnetic forces play a critical role similar to external excitation forces. It is shown that the increase in graphene content could lead the system from period-doubling motion into chaotic behavior. Moreover, an enhanced magnetic field strength may lower the minimum graphene concentration needed for period-doubling motion. This work provides new insights into controlling nonlinear vibrations of such systems through applied electromagnetic fields, emphasizing the importance of designing multifunctional nanocomposites in multi-physics coupled environments. The concentration of graphene filler would significantly affect the primary resonance and bifurcation and chaos behaviors of the system.