基于SPH法的板结土壤深耕技术研究
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摘要
耕作是农业文明的象征,也是耗能最多的田间作业。不断改进耕作机具和关键部件以利于精耕细作和节省能耗,历来是农民和业界追求的目标。但由于中国南方山区丘陵地带特别是茶园土壤,目前受原始土质条件限制,其土壤耕作环境恶劣,劳动强度大,严重影响山区丘陵地带的农业发展,因此需要开发和研制具有切土扭矩小,耕深大,操作平稳的作业机械。
为降低板结土壤深松机具的作业功耗,提出了反旋凿切与正旋深耕相结合的小型作业机的耕作机具的设想。针对板结土壤,本文采用有限元法着重分析了适合实际所需的正旋旋耕刀,研究的内容主要包括以下几个部分:
1、结合机械土壤动力学和土壤耕作机械理论的知识,以及实际所需,设计出正旋旋耕刀,并分析正旋旋耕的运动过程。
2、结合LS-DYNA的MAT147材料模型,建立了南方丘陵地带土壤的材料模型参数及土壤高速切削有限元数值仿真模型。采用ANSYS11.0/LS-DYNA软件,利用SPH法对正旋旋耕刀切削土壤过程进行了三维数值模拟。
3、通过SPH法对正旋旋耕土壤过程进行了三维数值模拟,从而得出不同参数下旋耕刀具的受力情况及数据,结合反旋凿切的仿真数据,进行刀具的分析和匹配,并设计相应的相位角。
利用SPH法对正旋旋耕土壤过程进行了三维数值模拟,从而得出不同参数下旋耕刀具的受力情况,结合反旋凿切的仿真数据,进行刀具的匹配并设计相应的相位角,使反旋凿切刀和正旋旋耕刀相互抵消各自的作用力,降低能耗,提高工作效率,从而开发出适合于在板结土壤上进行耕作的小型作业机。本研究方案所得数据和分析过程对于小型作业机的开发设计具有重要意义。
Farming is the symbol of agriculture and civilization, but also the most energy-intensive field work. The continuous improvement of farming equipment and key components in order to facilitate intensive and save energy consumption, has always been the farmers and the industry's goal. However, the foothills of mountains in southern China are currently subject to the original soil conditions, poor environment of soil tillage, labor intensity, which affects the agricultural development in mountainous hills. Therefore, researching and developing operating machine with characteristics of small ground-penetrating torque, large plow depth and stabilized operation is urgent.
In order to reduce the working power of tillage implement, made a combination of counter-rotating chisel-cut and deep plowing applied on small agricultural machine is proposed. For the compaction of soil, this paper focused on the finite element method analysis of the practical requirements for a positive spin rotary blade, the study mainly includes the following sections:
1、Combination of mechanical soil dynamics and soil tillage mechanical theory of knowledge, and practical needs are rotating rotary blade design and analysis the process of rotating rotary movement.
2、The MAT147 with LS-DYNA material models, the establishment of the Southern hills of soil material model parameters and soil high-speed cutting numerical finite element simulation model. Using ANSYS11.0/LS-DYNA software, using SPH method is rotating rotary blade cutting process on the soil of three-dimensional numerical simulation.
3、SPH method by rotating rotary soil processes are being carried out three-dimensional numerical simulation to arrive at different parameters of the force of rotary cutting tools and data, combined with anti-rotation chisel-cut simulation data, analysis and matching tools, and design the corresponding phase angle.
SPH method is applied to the three-dimensional numerical simulation for rotary soil process of rotating, and thus draws the force characteristics of rotary cutting tools under the different parameters. Combining with the simulation data of counter-rotating cutting chisel, the work of tool matching is done and relevant phase angle is designed. So it can make the force of Anti-screwdrivers rotary blade cutter and positive spin offset respectively. Accordingly, the small agricultural machinery can reduce energy consumption and improve efficiency. Based on these methods, we develop the small farming machinery which is fit for farming in compacted soil. The data and analysis program based on the study are of great significance for the small farming machinery.
为降低板结土壤深松机具的作业功耗,提出了反旋凿切与正旋深耕相结合的小型作业机的耕作机具的设想。针对板结土壤,本文采用有限元法着重分析了适合实际所需的正旋旋耕刀,研究的内容主要包括以下几个部分:
1、结合机械土壤动力学和土壤耕作机械理论的知识,以及实际所需,设计出正旋旋耕刀,并分析正旋旋耕的运动过程。
2、结合LS-DYNA的MAT147材料模型,建立了南方丘陵地带土壤的材料模型参数及土壤高速切削有限元数值仿真模型。采用ANSYS11.0/LS-DYNA软件,利用SPH法对正旋旋耕刀切削土壤过程进行了三维数值模拟。
3、通过SPH法对正旋旋耕土壤过程进行了三维数值模拟,从而得出不同参数下旋耕刀具的受力情况及数据,结合反旋凿切的仿真数据,进行刀具的分析和匹配,并设计相应的相位角。
利用SPH法对正旋旋耕土壤过程进行了三维数值模拟,从而得出不同参数下旋耕刀具的受力情况,结合反旋凿切的仿真数据,进行刀具的匹配并设计相应的相位角,使反旋凿切刀和正旋旋耕刀相互抵消各自的作用力,降低能耗,提高工作效率,从而开发出适合于在板结土壤上进行耕作的小型作业机。本研究方案所得数据和分析过程对于小型作业机的开发设计具有重要意义。
Farming is the symbol of agriculture and civilization, but also the most energy-intensive field work. The continuous improvement of farming equipment and key components in order to facilitate intensive and save energy consumption, has always been the farmers and the industry's goal. However, the foothills of mountains in southern China are currently subject to the original soil conditions, poor environment of soil tillage, labor intensity, which affects the agricultural development in mountainous hills. Therefore, researching and developing operating machine with characteristics of small ground-penetrating torque, large plow depth and stabilized operation is urgent.
In order to reduce the working power of tillage implement, made a combination of counter-rotating chisel-cut and deep plowing applied on small agricultural machine is proposed. For the compaction of soil, this paper focused on the finite element method analysis of the practical requirements for a positive spin rotary blade, the study mainly includes the following sections:
1、Combination of mechanical soil dynamics and soil tillage mechanical theory of knowledge, and practical needs are rotating rotary blade design and analysis the process of rotating rotary movement.
2、The MAT147 with LS-DYNA material models, the establishment of the Southern hills of soil material model parameters and soil high-speed cutting numerical finite element simulation model. Using ANSYS11.0/LS-DYNA software, using SPH method is rotating rotary blade cutting process on the soil of three-dimensional numerical simulation.
3、SPH method by rotating rotary soil processes are being carried out three-dimensional numerical simulation to arrive at different parameters of the force of rotary cutting tools and data, combined with anti-rotation chisel-cut simulation data, analysis and matching tools, and design the corresponding phase angle.
SPH method is applied to the three-dimensional numerical simulation for rotary soil process of rotating, and thus draws the force characteristics of rotary cutting tools under the different parameters. Combining with the simulation data of counter-rotating cutting chisel, the work of tool matching is done and relevant phase angle is designed. So it can make the force of Anti-screwdrivers rotary blade cutter and positive spin offset respectively. Accordingly, the small agricultural machinery can reduce energy consumption and improve efficiency. Based on these methods, we develop the small farming machinery which is fit for farming in compacted soil. The data and analysis program based on the study are of great significance for the small farming machinery.
引文
[1]夏晓东,吴崇友,张瑞林等.加大耕深型正转旋耕机研究设计初探[J].农业工程学报, 1999, 15(1): 69-72.
[2]丁为民,王耀华,彭嵩植.正、反转旋耕不同耕作性能的比较[J].南京农业大学学报, 2003, 26(3): 106-109.
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[13] Mouazen A.M, Nemenyi M. Tillage tool design by the finite element method: Part1. finite element modelling of soil plastic behaviour [J]. Agric.Engng. Res.,1999,72(1):37-51.
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[17]郭志军,周志立,佟金等.抛物线型切削面切削性能二维有限元分析[J].洛阳工学院学报, 2002, 23(4): 1-4.
[18] Rosa U.A,Wulfsohn D. Constitutive model for high speed tillage using narrow tools [J]. Terramechanics, 1999, 36(4): 221-234.
[19] Karmakar S, Kushwaha R.L. Simulation of soil deformation around a tillage tool using computationalfluid dynamics [J]. American Society of Agricultural Engineers, 2005, 48(3): 923-932.
[20]丁峻宏,李根国,金先龙等.盾构刀盘切削的三维并行数值模拟[J].计算机辅助工程, 2006,15(增刊): 303-307.
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[22] Susila E, Hryciw R.D. Large displacement FEM modeling of the conepenet ration test (CPT ) in normally consolidated sand [J]. Numer. And Meth. Geomech, 2003, 27(7): 585-602.
[23]王建华,杨磊,沈为平.有限元后验误差估计方法的研究进展[J].力学进展, 1990, 30(2): 175-190.
[24]丁峻宏,金先龙,郭毅之等.土壤切削大变形的三维数值仿真[J].农业机械学报, 2007, 38(4): 118-121.
[25]杜家瑶.耕作力学的开拓与探索[N].见:中国力学学会办公室、中国农业工程学会办公室编.力学与农业工程.北京:科学出版社, 1994, 21-25.
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[28] J.J Monaghan and R.A Gingold. Shock simulation by the particle method SPH [J]. Journal of Computational Physics, 1983, 52: 374-389.
[29] J.J Monaghan. Heat conduction with discontinuous conductivity [J]. Applied Mathematics Reports and Preprints, Monash University, 1995, 95-118.
[30]况蕙孙,蒋伯诚,张树发等.计算物理引论[M].长沙:湖南科学技术出版社, 1987.
[31] J.W Swegle, S.W Attaway, M.W Heinstein, etc. An Analysis of Smoothed Particle Hydrodynamics [R], Sandia Report SAND93-2513, Sandia National Laboratories, Albuquerque, NM,1994.
[32] G.R Liu, M.B Liu. Smoothed Particle Hydrodynamics:A meshfree particle method [M]. world Scientific Publishing Co.Pte. Ltd, 2003.
[33]张锁春.光滑质点流体动力学(SPH)方法[J].计算物理. 1996, 13(4): 395-395.
[34] J.J Monaghan, R.A Gingold,Shock simulation by the particle method SPH [J]. Comput. Phys. 1983(52): 374-389.
[35] Swegle, J.W, Hicks, D.L. and Attaway S.W. Smoothed particle hydrodynamics stability analysis [J]. Journal of Computational Physics, 1995.116(1): 123-134.
[36] Brian Schlatter. A Pedagogical Tool Using Smoothed Particle Hydrodynamics to Model Fluid Flow Past a System of Cylinders [D]. Thesis of Master degree, 1999.
[37] L.D Libersky, A.G Petschek, Smoothed particle hydrodynamics with strength of materials [J], Advances in the Free-Lagrange Method Lecture Notes in Physics. 1990(395)248-257.
[38] L.D Libersky, A.G Petschek, T.C Carney, J.R Hipp and F.A Allahdadi, High strain Lagrangian hydrodynamics a three-dimensional SPH code for dynamic material reponse [J]. Comput.Phys. 1993(109): 67-75.
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[56]丁为民,王耀华,彭嵩植.正、反转旋耕刀性能分析及切土扭矩比较试验[J].南京农业大学学报, 2001, 24(1): 113～117.
[2]丁为民,王耀华,彭嵩植.正、反转旋耕不同耕作性能的比较[J].南京农业大学学报, 2003, 26(3): 106-109.
[3]张雄等.无网格法-Meshless metheods[M],北京:清华大学出版社, 2004.
[4]华云龙,张伟,董务民.力学可以为农业现代化作贡献[J].力学进展, 1998, 28(3): 289-298.
[5]杜家瑶.耕作力学的开拓与探索[J].中国力学学会办公室、中国农业工程学会办公室编.力学与农业工程.科学出版社, 1994, 21-25.
[6] Mouazen A.M. Nemenyi M.Tillage tool design by the finite element method:Part 1.Finite element modeling of soil plastic behavior [J]. J Agric.Engng Res, 1999, 72(1): 37-51.
[7]姚禹肃.应用于耕具阻力预测中的力学方法[J].见:中国力学学会办公室、中国农业工程学会办公室编.力学与农业工程.北京:科学出版社, 1994, 116-122.
[8] Terzaghi K. Theoretical soilmechanics. Chapman and HillLtd [N], John Wiley and Sons Inc.New York, 1943.
[9] Chi L, Kushwaha R.L. Finite element analysis of forces on a plane soil blade [J]. Agric. Engng, 1989, 31(2): 135-140.
[10] Chi L, Kushwaha R.L. A non-linear 3-D finite element analysis of soil failure with tillage tools [J]. Journal of Terramechanics, 1990, 27(4): 343-366.
[11] Chi L, Kushwaha R.L. A non-linear three dimensional finite element analysis of soil failure with curved tillage tools[J]. 1990, ASAE Paper 90-1546.
[12]陆怀民,张云廉,刘晋浩.土壤切削弹粘塑性有限元分析[J].岩土工程学报, 1995, 17(2): 100-105.
[13] Mouazen A.M, Nemenyi M. Tillage tool design by the finite element method: Part1. finite element modelling of soil plastic behaviour [J]. Agric.Engng. Res.,1999,72(1):37-51.
[14] Arraya K, Gao R. A non-linear three-dimensional finite element analysis of subsoiler cutting with pressurized air injection [J]. agric.Engrg.Res. 1995, 61(2): 115-128.
[15] Kushwaha R.L, Zhang Z.X. Evaluation of factors and current approaches related to computerized design of tillage tools: a review.Journal of Terramechanics, 1998, 35(2): 69-86.
[16] Fielke J.M. Finite element modeling of the cutting edge of tillage implements with soil [J]. Agric. Eng. Res, 1999, 74(1): 91-101.
[17]郭志军,周志立,佟金等.抛物线型切削面切削性能二维有限元分析[J].洛阳工学院学报, 2002, 23(4): 1-4.
[18] Rosa U.A,Wulfsohn D. Constitutive model for high speed tillage using narrow tools [J]. Terramechanics, 1999, 36(4): 221-234.
[19] Karmakar S, Kushwaha R.L. Simulation of soil deformation around a tillage tool using computationalfluid dynamics [J]. American Society of Agricultural Engineers, 2005, 48(3): 923-932.
[20]丁峻宏,李根国,金先龙等.盾构刀盘切削的三维并行数值模拟[J].计算机辅助工程, 2006,15(增刊): 303-307.
[21]郭志军,佟金,任露泉等.耕作部件-土壤接触问题研究方法分析[J].农业机械学报, 2001, 32(4): 102-104.
[22] Susila E, Hryciw R.D. Large displacement FEM modeling of the conepenet ration test (CPT ) in normally consolidated sand [J]. Numer. And Meth. Geomech, 2003, 27(7): 585-602.
[23]王建华,杨磊,沈为平.有限元后验误差估计方法的研究进展[J].力学进展, 1990, 30(2): 175-190.
[24]丁峻宏,金先龙,郭毅之等.土壤切削大变形的三维数值仿真[J].农业机械学报, 2007, 38(4): 118-121.
[25]杜家瑶.耕作力学的开拓与探索[N].见:中国力学学会办公室、中国农业工程学会办公室编.力学与农业工程.北京:科学出版社, 1994, 21-25.
[26] Gingold R.A, Monaghan J.J. Smoothed particle hydrodynamics [J]. Theory and applications non-spherical Stars, 1977(18): 375-389.
[27] Lucy L.B, A numerical approach to the testing of the fission hypothesis [J]. Astron J, 1977, 88 (10): 1013-1024.
[28] J.J Monaghan and R.A Gingold. Shock simulation by the particle method SPH [J]. Journal of Computational Physics, 1983, 52: 374-389.
[29] J.J Monaghan. Heat conduction with discontinuous conductivity [J]. Applied Mathematics Reports and Preprints, Monash University, 1995, 95-118.
[30]况蕙孙,蒋伯诚,张树发等.计算物理引论[M].长沙:湖南科学技术出版社, 1987.
[31] J.W Swegle, S.W Attaway, M.W Heinstein, etc. An Analysis of Smoothed Particle Hydrodynamics [R], Sandia Report SAND93-2513, Sandia National Laboratories, Albuquerque, NM,1994.
[32] G.R Liu, M.B Liu. Smoothed Particle Hydrodynamics:A meshfree particle method [M]. world Scientific Publishing Co.Pte. Ltd, 2003.
[33]张锁春.光滑质点流体动力学(SPH)方法[J].计算物理. 1996, 13(4): 395-395.
[34] J.J Monaghan, R.A Gingold,Shock simulation by the particle method SPH [J]. Comput. Phys. 1983(52): 374-389.
[35] Swegle, J.W, Hicks, D.L. and Attaway S.W. Smoothed particle hydrodynamics stability analysis [J]. Journal of Computational Physics, 1995.116(1): 123-134.
[36] Brian Schlatter. A Pedagogical Tool Using Smoothed Particle Hydrodynamics to Model Fluid Flow Past a System of Cylinders [D]. Thesis of Master degree, 1999.
[37] L.D Libersky, A.G Petschek, Smoothed particle hydrodynamics with strength of materials [J], Advances in the Free-Lagrange Method Lecture Notes in Physics. 1990(395)248-257.
[38] L.D Libersky, A.G Petschek, T.C Carney, J.R Hipp and F.A Allahdadi, High strain Lagrangian hydrodynamics a three-dimensional SPH code for dynamic material reponse [J]. Comput.Phys. 1993(109): 67-75.
[39] Lewis B.A. Manual for LS-DYNA soil material model 147, Mclean, VA [R], USA: Federal Highway Administration Research and Development Turner-Fairbank Highway Research Center, 2004.
[40]张学言.岩土塑性力学[M].北京:人民交通出版社, 1993.
[41] Simo J.C, and J.W. Ju. Stress and Strain-Based Continuum Damage Models, Parts I and II [J] International Journal of Solids and Structures, 1987, 23(7).
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