采煤机镐形截齿截割过程的计算模拟
摘要
采煤机截割过程是一个复杂的过程,其根本原因在于煤岩结构及性质的复杂性。煤岩不是完整的质料均匀的各向同性体,它既不是完整弹性体,也不是理想塑性体,而具有明显的脆性。分析了煤岩在截割破碎过程中的物理和力学性质及破坏准则,这些是进行计算机模拟的基本前提。
通过对采煤机截割理论的分析,认识到采煤机截割过程主要包括四个阶段:变形阶段、裂纹阶段、压实核形成阶段及裂纹扩展及崩裂阶段,这四个阶段不断重复实现了煤岩的不断破碎和脱落。在截割过程中,作用在截齿上的载荷是在各种复杂且在空间上不断变化的条件下形成的,伴随大量的随机因素,可将截齿的受力简化为三向力:截割阻力、牵引阻力和侧向力。对截割过程影响的主要因素包括:截齿形状、截割速度、截割厚度、安装角及截槽形状等。
本文运用LS-DYNA对煤体的截割过程进行模拟,在模拟中由于模型相对简单,选择直接在ANSYS环境下直接建模。在模拟前还需对模型配置各自的材料模型、材料参数、约束条件及载荷等,其中材料模型的选择是个至关重要的问题,直接关系到模拟结果的可靠性。在模拟时选择了四种方案:变换截割速度、变换截割厚度、变换截齿锥角及变换安装角。通过模拟得到了各种截割条件下的三向阻力,对比分析同种方案中不同阻力的统计值,总结出了一定规律。运用Matlab对三向阻力结果进行了频谱分析,得到了频域中各载荷的能量分布曲线,从中分析出了各向载荷的主要频率,主要频率对截割过程的影响最大,关系到采煤机震动的剧烈程度和工作的稳定性,从而在进行采煤机结构的设计时要尽可能使采煤机的固有频率远离这些主要频率。通过对截割过程模拟的应力云图动画分析,展现了截割过程中煤体应力分布情况,加深了对截割过程的认识。
The cutting process of shearer is a complex process, because the strucrure and nature of coal is complex. The coal is not the entity of the same nature in every direction with regular qulity. It is neither the full elastic entity nor the complete plasticity entity, and it is obviously brittle.The paper analyses the physical, mechanics character and damage rule in cutting process, which provides the basic requirement for computer simulation.
Through analysis for the cutting theory of shearer,it is realized that the cutting process of shearer involves four periods: the deform period, the crack period, the compaction core forming period, the crack expandition and crumble period. The coal is constantly broken and falls off when the four periods continuously appear. In the cutting process, the loads on pick form in all kinds of complicated and constantly changeable space conditions which accompanies with many random factors. The forces on the pick is simplified to three direction forces: the cutting resistance, the pulling resistance and the side resistance. The main factors affecting the cutting process involves : the shape of pick, the cutting velocity, the cutting thickness, the install angle and the shape of cutting groove.
The paper simulates the cutting process of coal with LS-DYNA.The model is directly set up in ANASYS environment for the model is relatively simple in simulation.Before the simulation, it is necessary that material model ,material parameter, restrain qualification and loads should be offered. The choice of the material model is an important problem,it affects the reliability of simulation result.In simulation four schemes are chosen: the different cutting velocities, the different cutting thicknesses, the different cone angles and the different install angles. By simulation the three direction resistances in every cutting conditions are got. Compared with the statistics values of different resistances in the same scheme, some rules are concluded. With Matlab,the frequency spectrum of three direction resistances results are analysed, and energy distribution curves of every load in the frequency field are received. The main frequencies of every load are found out from the curves. The main frequency affects the cutting process greatly, it is attached with the fierce of vibration and work stabilization of the shearer. So inherent frequency of shearer should be far away from these main frequencies in the design of the shearer structure.By dynamic analysis of the stress distribution for the simulation of cutting process, the stress distribution of the coal model is found out, which makes the cutting process realized deeply.
通过对采煤机截割理论的分析,认识到采煤机截割过程主要包括四个阶段:变形阶段、裂纹阶段、压实核形成阶段及裂纹扩展及崩裂阶段,这四个阶段不断重复实现了煤岩的不断破碎和脱落。在截割过程中,作用在截齿上的载荷是在各种复杂且在空间上不断变化的条件下形成的,伴随大量的随机因素,可将截齿的受力简化为三向力:截割阻力、牵引阻力和侧向力。对截割过程影响的主要因素包括:截齿形状、截割速度、截割厚度、安装角及截槽形状等。
本文运用LS-DYNA对煤体的截割过程进行模拟,在模拟中由于模型相对简单,选择直接在ANSYS环境下直接建模。在模拟前还需对模型配置各自的材料模型、材料参数、约束条件及载荷等,其中材料模型的选择是个至关重要的问题,直接关系到模拟结果的可靠性。在模拟时选择了四种方案:变换截割速度、变换截割厚度、变换截齿锥角及变换安装角。通过模拟得到了各种截割条件下的三向阻力,对比分析同种方案中不同阻力的统计值,总结出了一定规律。运用Matlab对三向阻力结果进行了频谱分析,得到了频域中各载荷的能量分布曲线,从中分析出了各向载荷的主要频率,主要频率对截割过程的影响最大,关系到采煤机震动的剧烈程度和工作的稳定性,从而在进行采煤机结构的设计时要尽可能使采煤机的固有频率远离这些主要频率。通过对截割过程模拟的应力云图动画分析,展现了截割过程中煤体应力分布情况,加深了对截割过程的认识。
The cutting process of shearer is a complex process, because the strucrure and nature of coal is complex. The coal is not the entity of the same nature in every direction with regular qulity. It is neither the full elastic entity nor the complete plasticity entity, and it is obviously brittle.The paper analyses the physical, mechanics character and damage rule in cutting process, which provides the basic requirement for computer simulation.
Through analysis for the cutting theory of shearer,it is realized that the cutting process of shearer involves four periods: the deform period, the crack period, the compaction core forming period, the crack expandition and crumble period. The coal is constantly broken and falls off when the four periods continuously appear. In the cutting process, the loads on pick form in all kinds of complicated and constantly changeable space conditions which accompanies with many random factors. The forces on the pick is simplified to three direction forces: the cutting resistance, the pulling resistance and the side resistance. The main factors affecting the cutting process involves : the shape of pick, the cutting velocity, the cutting thickness, the install angle and the shape of cutting groove.
The paper simulates the cutting process of coal with LS-DYNA.The model is directly set up in ANASYS environment for the model is relatively simple in simulation.Before the simulation, it is necessary that material model ,material parameter, restrain qualification and loads should be offered. The choice of the material model is an important problem,it affects the reliability of simulation result.In simulation four schemes are chosen: the different cutting velocities, the different cutting thicknesses, the different cone angles and the different install angles. By simulation the three direction resistances in every cutting conditions are got. Compared with the statistics values of different resistances in the same scheme, some rules are concluded. With Matlab,the frequency spectrum of three direction resistances results are analysed, and energy distribution curves of every load in the frequency field are received. The main frequencies of every load are found out from the curves. The main frequency affects the cutting process greatly, it is attached with the fierce of vibration and work stabilization of the shearer. So inherent frequency of shearer should be far away from these main frequencies in the design of the shearer structure.By dynamic analysis of the stress distribution for the simulation of cutting process, the stress distribution of the coal model is found out, which makes the cutting process realized deeply.
引文
[1]戴绍诚等,高产高效综合机械化采煤技术与装备,北京,煤炭工业出版社,1998
[2]王庆康,采煤机破煤理论,煤炭工业出版社,1992
[3]刘萍,采煤机滚筒截装过程的运动学分析,贵州工业大学学报,2004,33(6),98-102
[4]李晓豁,王明铁等,影响采掘机械截割块率和粉尘的因素分析,辽宁工程技术大学学报,1998,17(6),598-601
[5]李晓豁,刘春生,李萍,滚筒式采煤机的动力学模型,黑龙江矿业学院学报,2000(6),1-3
[6]徐志英,岩石力学,中国水利水电出版社,1993
[7]何涛,ANSYS10.0/LS-DYNA非线性有限元分析实例指导教程,机械工业出版社,2007
[8]王洪英,采煤机镐形齿滚筒载荷的计算机模拟,[学位论文],阜新,辽宁工程技术大学,2002
[9]王春华,姚保恒等,采煤机截齿截割煤岩的实验研究,矿山机械,2001(12),13-14
[10]宁仲良,朱华双,镐形截齿应力分布规律研究,西安科技学院学报,2003,23(9),325-327
[11]顼秀丽,田取珍,冲击破煤过程的计算机仿真,太原理工大学学报,2005,36(3),267-269
[12]岳欣,陶驰东,采煤机滚筒优化设计数学模型,煤矿机电,1996(3),2-8
[13]李晓豁,赵岐刚,连续采煤机截割部的运动及力学分析,黑龙江科技学院学报,2005,15(5),282-284
[14]王英山,采煤机滚筒截煤载荷的模拟,煤矿机电,1996(2),2-4
[15]张守宝,冲击采煤的应力波传播分析及研究,[学位论文],太原,太原理工大学,2005
[16]郭迎福,张永忠,采煤机滚筒载荷计算机仿真及降低载荷波动的对策,矿山机械,2001(5),24-26
[17]姚宝恒,镐形截齿破煤机理研究,[学位论文],阜新,辽宁工程技术大学,2000
[18]王启广,谢锡纯,模拟截割材料的相似设计,煤矿机电,1994(5),17-19
[19]李晓豁,麻晓红,于信伟,连续采煤机滚筒载荷的计算机模拟,矿山机械,2005(12),19-20
[20]王春华,截齿截割作用下煤体变形破坏规律研究,[学位论文],阜新,辽宁工程技术大学,2004
[21]刘春生,采煤机截齿截割阻力曲线分形特征研究,煤炭学报,2004(2),115-118
[22]李晓豁,采煤机螺旋滚筒随机载荷的模拟,黑龙江科技学院学报,2001,11(4),8-10
[23]胡应曦,陈启梅,采煤机滚筒截齿配置及滚筒转速与牵引速度匹配关系的分析,贵州工业大学学报,2001,30(6),15-17
[24]蔡大文,采煤机截齿的三维应力分析,陕西煤炭技术,1995(12),36-38
[25]于信伟,复杂煤层模拟及连续采煤机截割机构参数优化,[学位论文],阜新,辽宁工程技术大学,2005
[26]李国华等,用真实煤样进行煤炭截割的试验研究,煤矿机械,2001(11),20-22
[27]牛东民,煤炭切削力学模型的研究,煤炭学报,1994,19(5),526-530
[28]Hurt K G,The Design of Advancing Shearer Drums,Colliery Guardian,1988(12)
[29]Evans 1,Basic Mechanics of the Point-Attack Pick,Colliery Guardian,1982
[30]Evans 1,Optimum Line Spacing for cutting Picks,Mining Engineer,London,Jan,1982
[31]Hurt K G.A Laboratory Study of Rock cutting,21st US symposium on Rock Mechanics,U of Missouri,1980
[32]Robert Sturm and Hans Peter Steyrer,Use of accessory zircon for the quantification of volume changes in ductile shear zones cutting plutonic rocks,Chemic der Erde-Geochemistry,63(1),2003,31-54
[33]H.Alehossein and M.Hood,An application of linearised dimensional analysis to rock cutting.International Journal of Rock Mechanics and Mining Sciences,1999,36(5),701-709
[34]O.G.Checkina,I.G.Goryacheva and V.G.Krasnik,The model for tool wear in rock cutting,Wear,198(1-2),1996(10),33-38
[35]M.Hood and H.Alehossein,A development in rock cutting technology,International Journal of Rock Mechanics and Mining Sciences, 37(1-2), 2000(1),297-305
[36]S.Q.Kou,P.-A. Lindqvist,C.A.Tang and X.H.Xu ,Numerical simulation of the cutting of inhomogeneous rocks, International Journal of Rock Mechanics and Mining Sciences,1999,36(5),711-717
[37]C.Balci and N.Bilgin, Correlative study of linear small and full-scale rock cutting tests to select mechanized excavation machines.International Journal of Rock Mechanics and Mining Sciences,2007(4),44(3),468-476
[38]N.Gunes Yilmaz,M. Yurdakul,R.M.Goktan, Prediction of radial bit cutting force in high-strength rocks using multiple linear regression analysis, International Journal of Rock Mechanics & Mining Sciences,2007,44(2),962-970
[39]R.M. Goktan and N. Gunes, A comparative study of Schmidt hammer testing procedures with reference to rock cutting machine performance prediction, International Journal of Rock Mechanics and Mining Sciences, 2005,42(3),466-472
[40]Prasad Kaitkay and Shuting Lei, Experimental study of rock cutting under external hydrostatic pressure, Journal of Materials Processing Technology, 2005,159(2),206-213
[2]王庆康,采煤机破煤理论,煤炭工业出版社,1992
[3]刘萍,采煤机滚筒截装过程的运动学分析,贵州工业大学学报,2004,33(6),98-102
[4]李晓豁,王明铁等,影响采掘机械截割块率和粉尘的因素分析,辽宁工程技术大学学报,1998,17(6),598-601
[5]李晓豁,刘春生,李萍,滚筒式采煤机的动力学模型,黑龙江矿业学院学报,2000(6),1-3
[6]徐志英,岩石力学,中国水利水电出版社,1993
[7]何涛,ANSYS10.0/LS-DYNA非线性有限元分析实例指导教程,机械工业出版社,2007
[8]王洪英,采煤机镐形齿滚筒载荷的计算机模拟,[学位论文],阜新,辽宁工程技术大学,2002
[9]王春华,姚保恒等,采煤机截齿截割煤岩的实验研究,矿山机械,2001(12),13-14
[10]宁仲良,朱华双,镐形截齿应力分布规律研究,西安科技学院学报,2003,23(9),325-327
[11]顼秀丽,田取珍,冲击破煤过程的计算机仿真,太原理工大学学报,2005,36(3),267-269
[12]岳欣,陶驰东,采煤机滚筒优化设计数学模型,煤矿机电,1996(3),2-8
[13]李晓豁,赵岐刚,连续采煤机截割部的运动及力学分析,黑龙江科技学院学报,2005,15(5),282-284
[14]王英山,采煤机滚筒截煤载荷的模拟,煤矿机电,1996(2),2-4
[15]张守宝,冲击采煤的应力波传播分析及研究,[学位论文],太原,太原理工大学,2005
[16]郭迎福,张永忠,采煤机滚筒载荷计算机仿真及降低载荷波动的对策,矿山机械,2001(5),24-26
[17]姚宝恒,镐形截齿破煤机理研究,[学位论文],阜新,辽宁工程技术大学,2000
[18]王启广,谢锡纯,模拟截割材料的相似设计,煤矿机电,1994(5),17-19
[19]李晓豁,麻晓红,于信伟,连续采煤机滚筒载荷的计算机模拟,矿山机械,2005(12),19-20
[20]王春华,截齿截割作用下煤体变形破坏规律研究,[学位论文],阜新,辽宁工程技术大学,2004
[21]刘春生,采煤机截齿截割阻力曲线分形特征研究,煤炭学报,2004(2),115-118
[22]李晓豁,采煤机螺旋滚筒随机载荷的模拟,黑龙江科技学院学报,2001,11(4),8-10
[23]胡应曦,陈启梅,采煤机滚筒截齿配置及滚筒转速与牵引速度匹配关系的分析,贵州工业大学学报,2001,30(6),15-17
[24]蔡大文,采煤机截齿的三维应力分析,陕西煤炭技术,1995(12),36-38
[25]于信伟,复杂煤层模拟及连续采煤机截割机构参数优化,[学位论文],阜新,辽宁工程技术大学,2005
[26]李国华等,用真实煤样进行煤炭截割的试验研究,煤矿机械,2001(11),20-22
[27]牛东民,煤炭切削力学模型的研究,煤炭学报,1994,19(5),526-530
[28]Hurt K G,The Design of Advancing Shearer Drums,Colliery Guardian,1988(12)
[29]Evans 1,Basic Mechanics of the Point-Attack Pick,Colliery Guardian,1982
[30]Evans 1,Optimum Line Spacing for cutting Picks,Mining Engineer,London,Jan,1982
[31]Hurt K G.A Laboratory Study of Rock cutting,21st US symposium on Rock Mechanics,U of Missouri,1980
[32]Robert Sturm and Hans Peter Steyrer,Use of accessory zircon for the quantification of volume changes in ductile shear zones cutting plutonic rocks,Chemic der Erde-Geochemistry,63(1),2003,31-54
[33]H.Alehossein and M.Hood,An application of linearised dimensional analysis to rock cutting.International Journal of Rock Mechanics and Mining Sciences,1999,36(5),701-709
[34]O.G.Checkina,I.G.Goryacheva and V.G.Krasnik,The model for tool wear in rock cutting,Wear,198(1-2),1996(10),33-38
[35]M.Hood and H.Alehossein,A development in rock cutting technology,International Journal of Rock Mechanics and Mining Sciences, 37(1-2), 2000(1),297-305
[36]S.Q.Kou,P.-A. Lindqvist,C.A.Tang and X.H.Xu ,Numerical simulation of the cutting of inhomogeneous rocks, International Journal of Rock Mechanics and Mining Sciences,1999,36(5),711-717
[37]C.Balci and N.Bilgin, Correlative study of linear small and full-scale rock cutting tests to select mechanized excavation machines.International Journal of Rock Mechanics and Mining Sciences,2007(4),44(3),468-476
[38]N.Gunes Yilmaz,M. Yurdakul,R.M.Goktan, Prediction of radial bit cutting force in high-strength rocks using multiple linear regression analysis, International Journal of Rock Mechanics & Mining Sciences,2007,44(2),962-970
[39]R.M. Goktan and N. Gunes, A comparative study of Schmidt hammer testing procedures with reference to rock cutting machine performance prediction, International Journal of Rock Mechanics and Mining Sciences, 2005,42(3),466-472
[40]Prasad Kaitkay and Shuting Lei, Experimental study of rock cutting under external hydrostatic pressure, Journal of Materials Processing Technology, 2005,159(2),206-213