Intruder trajectory tracking in a three-dimensional vibration-driven granular system:Unveiling the mechanism of the Brazil nut effect

作     者：李拓 程可 彭政 杨晖 厚美瑛 Tuo Li;Ke Cheng;Zheng Peng;Hui Yang;Meiying Hou

作者机构：School of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China Soft Matter LaboratoryInstitute of PhysicsChinese Academy of SciencesBeijing 100190China School of PhysicsCentral South UniversityChangsha 410012China College of Medical InstrumentationShanghai University of Medicine&Health SciencesShanghai 201318China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2023年第32卷第10期

页      面：106-111页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0702[理学-物理学] 

基　　金：Project supported by the Space Application System of China Manned Space Program the National Natural Science Foundation of China(Grant Nos.12072200 and 12002213) 

主　　题：granular matter segregation Brazil nut effect vibro-fluidization 

摘      要：We employ a Hall-effect magnetic sensor array to accurately track the trajectory of a single magnetic sphere,referred to as the“intruder,within a three-dimensional vibro-fluidized granular bed to unravel the underlying physical mechanism governing the motion of the *** the acceleration range of 3.5 g≥Γ≥1.5 g,we find that,regardless of the intruder s initial position,it consistently reaches the same equilibrium depth when the vibration acceleration(Γ)and frequency(ω)are ***Γ≤2.5 g,the equilibrium position lies on the surface of the granular bed,while forΓ2.5 g,it shifts below the ***,intruders with different densities exhibit varying equilibrium depths,with higher density resulting in a deeper equilibrium *** understand the mechanism behind the intruder s upward or downward motion,we measure its rising or sinking velocities under different vibration *** findings demonstrate that the rising velocity of the intruder,under varying vibration accelerations(Γ)and frequencies(ω),can be collapsed using the ratioΓ/ω,while the sinking velocity remains unaffected by the vibration *** confirms that the upward motion of the larger sphere,associated with the Brazil nut effect,primarily arises from the void-filling mechanism of the bed ***,our experiments reveal that the presence of convection within the bed particles has minimal impact on the motion of the intruder.