Showing papers by "Yueming Li published in 2020"
TL;DR: In this paper, a nonlinear energy sink (NES) enhanced by a giant magnetostrictive material (GMM) energy harvester is proposed to suppress the nonlinear aeroelastic responses of a cantilevered trapezoidal plate in hypersonic airflow.
43 citations
TL;DR: In this article, a locally resonant elastic metamaterial (LREM) based on liquid solid interaction (LSI) is proposed, which can attenuate flexural wave in broad low frequency range.
19 citations
TL;DR: In this paper, a dual-functional metamaterial, with cylindrical stub periodically attached on the multilayered plate, is initially designed and investigated numerically and experimentally.
9 citations
TL;DR: In this paper, a two-dimensional phononic crystal with heat flux manipulation and wide bandgaps of out-of-plane modes within the low-frequency range was presented, where rubber-coated metal cylinders are periodically embedded in the anisotropic matrix to obtain the lowfrequency bandgap of out of plane modes.
Abstract: This study presents a two-dimensional phononic crystal with heat flux manipulation and wide bandgaps of out-of-plane modes within the low-frequency range. The anisotropic matrix made of spiral-multilayered materials with different thermal conductivities, and the coating layer inserted with metal are designed for heat flux manipulation. Rubber-coated metal cylinders are periodically embedded in the anisotropic matrix to obtain the low-frequency bandgaps of out-of-plane modes. Numerical simulation is carried out to validate the heat and elastic characteristics of the spiral-multilayered anisotropic structure and reveal the effects of the laying angle and temperature on the bandgaps. Subsequently, a spiral-multilayered plate with periodic structures is studied, which shows an obvious vibration attenuation in the frequency ranges of the bandgaps and a deflected heat flux from the initial propagation direction. In the experimental investigation, the multi-phase spiral-multilayered anisotropic plate is simplified to a single-phase anisotropic plate made of aluminum. The characteristics of this type of anisotropic phononic crystal structure may pave the way for the design of a new kind of thermo-acoustic metamaterial serving in combined thermal and acoustic environments.
8 citations
TL;DR: In this article, an oscillator with one sloping "buncher" and one "catcher" cavity with an inclination angle of 5° and shaped like a "clamp" was proposed.
Abstract: We present the design of an oscillator that is an evolution of our previously proposed “clamp klystron.” In this new embodiment, we utilize sloping cavities and increase the operating frequency to 94 GHz and 100 GHz (W-band). In this study, we utilized the UNIPIC particle-in-cell code. Simulations confirmed that this new oscillator with one sloping “buncher” cavity and one sloping “catcher” cavity with an inclination angle of 5° and shaped like a “clamp” produces 700 kW output power with an efficiency of 7.1% at 94 GHz when powered using an applied voltage U = 90 kV and beam current 110 A. When one sloping “buncher” cavity and one sloping “catcher” cavity are utilized with an inclination angle of 15°, the oscillator produces 270 kW output power with 3.0% efficiency at 100 GHz when powered using the same electron beam parameters. If two oscillators with sloping cavities along the z-axis are combined serially, then the output power can be as high as 800 kW with 8.0% efficiency at 100 GHz. This new oscillator design can be a promising approach to high power millimeter wave source designs at W-band and higher frequencies.