顆粒系統(tǒng)在水平振動作用下表現(xiàn)出復(fù)雜的現(xiàn)象,包括分離、對流與分布圖案,對農(nóng)業(yè)、采礦、制藥、地質(zhì)、土木工程等發(fā)展具有重要意義。以前的理論和實驗工作大多研究了豎向振動的影響,較少探索水平振動對顆粒系統(tǒng)對流運動與分布模式的影響。在水平振動的顆粒系統(tǒng)中,影響顆粒運動與分布的重要因素主要包括顆粒粒徑比、顆粒物性、能量輸入、振動方向和邊界條件等。在本文中,我們將分別研究水平振動作用下單組分顆粒體系單層床層、雙組分顆粒體系單層床層與雙組分顆粒體系多層床層中顆粒的對流運動與分布圖案。首先,我們將總質(zhì)量500g、粒徑d=8.0 ± 0.2 mm的活性氧化鋁球形顆粒放入正方形容器形成單組分顆粒體系的單層床層。容器邊長LX=LY=25 cm,高LZ= 18 cm。在容器上施加水平振動,振動頻率分別固定為5 Hz、10 Hz和15 Hz,無量綱振動加速度Γ=0.8～1.4。在實驗中,我們發(fā)現(xiàn)單組分顆粒體系的單層床層在水平振動作用下形成了四種不同的密度分布區(qū)域,即固態(tài)區(qū)、團簇區(qū)、氣態(tài)區(qū)和空區(qū),以及顆粒從容器的一個角落跳起形成多層結(jié)構(gòu)的3D狀態(tài)。研究發(fā)現(xiàn)轉(zhuǎn)動慣量I對顆粒系統(tǒng)的能量耗散和對流運動有重要的影響,且有I∝... 

【文章來源】：北京科技大學(xué)北京市 211工程院校 教育部直屬院校

【文章頁數(shù)】：115 頁

【學(xué)位級別】：博士

【文章目錄】：
Acknowledgements
摘要
Abstract
1 Literature Review
    1.1 Introduction
    1.2 Convection in Horizontally Vibrated Granular Materials
    1.3 Segregation in Horizontal Vibrated Systems
    1.4 Pattern Formation in Horizontally Vibrated Granular Materials
    1.5 Industrial Application of Granular matters
    1.6 Thesis Outline
2 Experimental Apparatus and Techniques
    2.1 Vibration Control System
        2.1.1 Front-End Amber
        2.1.2 Front board
        2.1.3 Rear board
        2.1.4 Camera
    2.2 Particle Image Velocimetry(PIV)
3 Moment of Inertia and Energy Dissipation in Mono-Size Monolayer Particles System
    3.1 States Observed in Monolayer System
        3.1.1 State at 5 Hz
        3.1.2 State at 10 Hz
        3.1.3 State at 15 Hz
    3.2 Region Formation in Monolayer Particles System
        3.2.1 Regions at 5 Hz
        3.2.2 Regions at 10 Hz
        3.2.3 Regions at 15 Hz
    3.3 Results Analysis
        3.3.1 Energy Dissipation in the System
        3.3.2 Effect of Moment of Inertia on Convection
    3.4 Summary
4 Regions Development and Convection Modes in Mono-Size Monolayer Particles System
    4.1 Regions Development and Convection Motion
        4.1.1 Regions Development in Non-Convection Mode
        4.1.2 Regions Development in Two Convection Rolls Mode
        4.1.3 Regions Development in One Roll Clockwise Convection Mode
        4.1.4 Regions Development in One Roll Counter-Clockwise Convection Mode
        4.1.5 Regions Development in 3D State Mode
    4.2 Regions Kinetic Energy Effects on Convection Mode
    4.3 Summary
5 Stripe Formation and Convection Motion of Binary Monolayer Particles System
    5.1 Phase Detected in the System
        5.1.1 Evolution of Clusters
        5.1.2 Formation of Stripe Patterns
        5.1.3 One Convection Roll
        5.1.4 Two Convection Rolls
        5.1.5 Numerous Convection Rolls
    5.2 Phase Development in System
        5.2.1 Mechanisms Involved in the Evolution of Clusters
        5.2.2 Mechanism of Stripe Pattern Formation
        5.2.3 Mechanism of One Convection Roll
        5.2.4 Mechanism of Two or More Convection Rolls
    5.3 Summary
6 Convection Rolls and Individual Particles Movement of Binary Particles Deep Layer System
    6.1 Convection Patterns
        6.1.1 Convection Pattern at 5 Hz
        6.1.2 Convection Pattern at 10 Hz
        6.1.3 Convection Pattern at 15 Hz
        6.1.4 Individual Particles Movements
    6.2 Heap Position and Convection Rolls
    6.3 Summary
7 Conclusions
References
Resume
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