The classical-quantum analogue offers a new platform for exploring extreme dynamic control of mechanical systems.In this work,the concept of the stimulated adiabatic passage of quantum states is extended to mechanical...The classical-quantum analogue offers a new platform for exploring extreme dynamic control of mechanical systems.In this work,the concept of the stimulated adiabatic passage of quantum states is extended to mechanical systems for achieving unidirectional energy transportation.The mechanical analog of stimulated adiabatic passage is realized in three mechanical resonators coupled with the time-varying stiffness,which are delicately modulated to mimic the selective population of quantum states.Based on the tight-binding approximation,an analytical model for the classical-quantum analogue of the adiabatic passage effect is established to realize the one-way energy transfer control.Numerical results demonstrate that the vibration energy acquired from an initially excited resonator can be transferred to the target one via an intermediate resonator,while flow in the reverse direction is prohibited due to energy localization in the intermediate resonator.The model holds application potentials in energy suppression and harvesting,and offers promising prospects for unidirectional wave and vibration control.展开更多
Damped acoustic systems have a limited quality factor due to intrinsic loss.By introducing gain elements,a method to enhance the quality factor of damped systems is proposed based on the concept of bound states in the...Damped acoustic systems have a limited quality factor due to intrinsic loss.By introducing gain elements,a method to enhance the quality factor of damped systems is proposed based on the concept of bound states in the continuum(BICs).The acoustic model under study is a two-port waveguide system installed with two side Helmholtz resonators connected by a coupling tube.Based on the temporal coupled-mode theory,a Hamiltonian matrix with both intrinsic and radiation losses is used to characterize the resonance behavior of the coupled resonators.To achieve a high quality factor,acoustic gain is introduced to compensate the intrinsic loss,leading the Hamiltonian parameters toward a quasi-BIC condition.Numerical simulation demonstrates a gain-assisted and quasi-BIC-supported extremely high quality factor in damped acoustic systems.The concept is further utilized to design a sensor model for particle size detection.The enhanced sensing performance due to high quality factors is numerically demonstrated.The findings suggest potential applications in acoustic sensing and detection devices.展开更多
The main contribution of this work is a comprehensive overview of the many years of research on various inter-facial forces with distinct flow structure transitions in liquid-gas multiphase flow in vertical columns.In...The main contribution of this work is a comprehensive overview of the many years of research on various inter-facial forces with distinct flow structure transitions in liquid-gas multiphase flow in vertical columns.Injecting a gas phase into a liquid phase result in a fluid dynamic phenomenology that is substantial,magnetizing,and fascinating.Bubble columns modelling functioning in the bubbly,slug,churn,and annular turbulent flow regime is a major challenge due to their complicated and ephemeral nature.An important modelling choice is how to represent the bubble size distribution.This may be accomplished in several ways,from the relatively simple one of utilizing a single representative bubble size to more intricate techniques.To evaluate the computational findings,we have analysed and discussed several turbulence models in this comparative research.Furthermore,this review summarises the current inter-facial force models,which include turbulent dispersion force,lift force,drag force,wall lubrication force,and virtual mass force.The models of Grace,Tomiyama,Zuber,Antel,Legendre,Burns,and Naumann universal Hosokawa are used,respectively.展开更多
基金supported by the National Key R&D Program of China(2024YFB3408700 and 2024YFB3408702)the National Natural Science Foundation of China(Grant Numbers 12225203,12402100,11991030,11991033,11622215,and 11872111)the 111 project(Grant Number B16003).
文摘The classical-quantum analogue offers a new platform for exploring extreme dynamic control of mechanical systems.In this work,the concept of the stimulated adiabatic passage of quantum states is extended to mechanical systems for achieving unidirectional energy transportation.The mechanical analog of stimulated adiabatic passage is realized in three mechanical resonators coupled with the time-varying stiffness,which are delicately modulated to mimic the selective population of quantum states.Based on the tight-binding approximation,an analytical model for the classical-quantum analogue of the adiabatic passage effect is established to realize the one-way energy transfer control.Numerical results demonstrate that the vibration energy acquired from an initially excited resonator can be transferred to the target one via an intermediate resonator,while flow in the reverse direction is prohibited due to energy localization in the intermediate resonator.The model holds application potentials in energy suppression and harvesting,and offers promising prospects for unidirectional wave and vibration control.
基金supported by the National Natural Science Foundation of China(Grant Nos.12225203,11622215,and 11872111)the 111 Project(Grant No.B16003).
文摘Damped acoustic systems have a limited quality factor due to intrinsic loss.By introducing gain elements,a method to enhance the quality factor of damped systems is proposed based on the concept of bound states in the continuum(BICs).The acoustic model under study is a two-port waveguide system installed with two side Helmholtz resonators connected by a coupling tube.Based on the temporal coupled-mode theory,a Hamiltonian matrix with both intrinsic and radiation losses is used to characterize the resonance behavior of the coupled resonators.To achieve a high quality factor,acoustic gain is introduced to compensate the intrinsic loss,leading the Hamiltonian parameters toward a quasi-BIC condition.Numerical simulation demonstrates a gain-assisted and quasi-BIC-supported extremely high quality factor in damped acoustic systems.The concept is further utilized to design a sensor model for particle size detection.The enhanced sensing performance due to high quality factors is numerically demonstrated.The findings suggest potential applications in acoustic sensing and detection devices.
基金supported by the National Science Foundation for Distinguished Young Scholars of China(No.52425903)the National Natural Science Foundation of China(No U2106225)Jiangsu Excellent Post-doctoral Program(2023ZB890).
文摘The main contribution of this work is a comprehensive overview of the many years of research on various inter-facial forces with distinct flow structure transitions in liquid-gas multiphase flow in vertical columns.Injecting a gas phase into a liquid phase result in a fluid dynamic phenomenology that is substantial,magnetizing,and fascinating.Bubble columns modelling functioning in the bubbly,slug,churn,and annular turbulent flow regime is a major challenge due to their complicated and ephemeral nature.An important modelling choice is how to represent the bubble size distribution.This may be accomplished in several ways,from the relatively simple one of utilizing a single representative bubble size to more intricate techniques.To evaluate the computational findings,we have analysed and discussed several turbulence models in this comparative research.Furthermore,this review summarises the current inter-facial force models,which include turbulent dispersion force,lift force,drag force,wall lubrication force,and virtual mass force.The models of Grace,Tomiyama,Zuber,Antel,Legendre,Burns,and Naumann universal Hosokawa are used,respectively.
