ls-dyna修改k文件总结

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LS_Dyna的问题总结

一、影响穿透的一些因素解释I.接触厚度接触厚度定义的是一个参数——当接触体/面相互穿透的距离大于接触厚度时，程序将不计算这个接触，即认为没有接触了。

什么是接触厚度与距离？在自动接触中，接触厚度是一个默认值，大概是面厚度的几倍，在普通接触中，接触厚度无穷大。

II.壳厚度和接触厚度1. 壳厚度：影响刚度和单元质量；2. 接触厚度：①决定解除中的厚度偏移量；②并不影响刚度或壳体质量；③默认接触厚度等于壳厚度；④可以在*CONTACT 或*PART_CONTACAT 中直接缩放接触厚度；⑤在穿透节点被释放之前影响最大允许穿透深度。

III.运动速度对穿透的影响如果物体相对运动速度过大，在一个时间步长中所走过的距离会远超过一个单元的尺寸，若缩小时间步长，即缩小在一个时间步长内所走过的距离和单元尺寸的差异，基础检查可以正常进行，若初速度过高，会搜索不到接触，计算会出现问题。

IV.非对称接触算法中，主从面的定义原则①粗网格表面定义为主面，细网格表面为从面；②主从面相关材料刚度相差悬殊，材料刚度大的一面为主面；③平直或者凹面为主面，凸面为从面。

V.接触刚度的影响穿透可以认为是一种虚拟穿透，如果设定的穿透刚度（fkn）值，就可以减小这种穿透，但却不可避免。

如果fkn 值过大，会使到那元刚度病态，而不能求解。

二、穿透的可能解决方案I.接触方面：1. 修改接触类型，尝试自动接触类型：①STS（面面接触），当一个体的表面穿透另外一个体的表面是创建②SS（单面接触），当一个体的表面自身接触或者接触另一个体的表面时创建2. 接触定义存在问题：①增加接触刚度因子②改变接触面的主从设置，将刚体设置为主面，同时使用单向接触③修改关键字CONTROL_CONTACT中RWPNAL=23. 接触穿透距离超过了接触厚度，从而不再计算接触；4. 如果两个接触体的材料属性和网格差别较大，可以修改SOFT值为1 或者2.5. 接触群组设置不直接用PART，将可能接触的地方设置为segment；6. 修改摩擦系数：Fs和Fd通常设置为相同的值，避免额外的噪声产生。

汽车碰撞分析LS_DYNA控制卡片设置.

控制卡片参数设置
8. CONTROL_PARALLEL 并行计算控制，最大可以使用4个CPU。
9. CONTROL_SHELL
壳单元控制
10. CONTROL_TERMINATION 设置如下：
控制卡片参数设置
11. CONTROL_TERMINATION 计算终止控制卡片，控制计算终止时间。
12. DATABASE_BINARY_D3DUMP 设置如下：
汽车碰撞分析LS-DYNA 控制卡片的设置
作者:张远岭
2011-4-14
控制卡片
碰撞分析控制卡片包括求解控制和结果输出控制，其中KEYWORD、 CONTROL_TERMINATION、 DATABASE_BINARY_D3PLOT是必不可少的。其他一些控制卡片如沙漏能控制、时间步控制、接触控制等则对计算过程进行控制，以便在发现模型中存在错误时及时的终止程序。后面将逐一介绍碰撞分析中经常用到的控制卡片，并对每个卡片的作用进行说明。
设置如下：
控制卡片参数说明
*CONTROL_TERMINATION $ ENDTIM ENDCYC DTMIN 150 0 0.0
ENDENG 0.0
ENDMAS 0.0
ENDTIM：强制终止计算时间，必选，默认0.0； ENDCYC：终止循环。在计算终止时间之前，程序达到指定循环次数即终止计算。 DTMIN：确定最小时间步长TSMIN的因子。TSMIN=DTMIN * DTSTART，其中DTSTART为程序自动确定的初始步长。当迭代步长小于TSMIN时，程序终止。 ENDENG：能量改变百分比，超过设定值则终止计算。默认0.0，不起作用； ENDMAS：质量变化百分比，超过设定值则终止计算。仅用于质量缩放DT2MS被使用时。默认0.0 ，不起作用。

LS-dyna-常见问题汇总2[1].0

资料来源：网络和自己的总结更新时间： 2008-10-12
LS-DYNA 常见问题汇总 2.0
yuminhust2005
2008-10-12
目录
1. 2. 3. 4. 5. 6. 7. 8. LS-DYNA 简介 .............................................................................................................................................................1 单位制度 ...................................................5 质量缩放 .........................................................................................................................................................................6 长分析时间 .....................................................................................................................................................................7 准静态 .............................................................................................................................................................................8 计算不稳定 .....................................................................................................................................................................9 负体积 ...........................................................................................................................................................................10 能量平衡 .......................................................................................................................................................................11

Ls-dyna总结

差别：计算成本
• 隐式分析的计算成本
– 模型大小
– 非线性程度 – 时间步个数
Training Manual
Explicit Dynamics with ANSYS/LSDYNA
•
显式分析的计算成本
– 模型大小
– 临界时间步 • 单元边长 • 声波速度:
– 杨氏模量
– 密度 – 终止时间
001322 10 JAN 2000 13-4
ANSYS/LS-DYNA的计算时间估计
TCPU k N Elem t
TCPU = 总的CPU时间 k = 系统因子 SGI PowerIndigo2 SGI Crimson 100 MHz HP 730 Nelem = 单元数 t = 模拟时间 c = 声速 lmin = 最短的单元长度
Training Manual
Explicit Dynamics with ANSYS/LSDYNA
第 13 章总结
本章目的
1. 描述显式与隐式分析的区别
Training Manual
Explicit Dynamics with ANSYS/LSDYNA
2. 回顾各个部分的注意事项
a. 建模 b. 材料 c. 接触 d. 加载 e. 概要
•
学会怎样使用 LS-TAURUS. 使用 EDOPT 命令来得到 d3plot 和 d3thdt 文件. LS-TAURUS 能较好的支持某些特定类型的后处理。 ( 例如：失效单元).
001322 10 JAN 2000 13-13
协调单位
Mass kg kg kg kg kg gm gm gm gm ton lbf-s2/in slug Length m cm cm cm mm cm cm mm mm mm in ft Time s s ms ms ms s ms s ms s s s Force N 1e-02N 1e+04N 1e+10N kN dyne 1e+07N 1e-06N N N lbf lbf Stress Pa Energy Joule r(steel) 7.83e+03 7.83e-03 7.83e-03 7.83e-03 7.83e-06 7.83e+00 7.83e+00 7.83e-03 7.83e-03 7.83e-09 7.33e-04 1.52e=01

lsdyna常见问题汇总

LYDYNA能量平衡GLSTAT(参见*database_glstat)文件中报告的总能量是下面几种能量的和：内能internal energy动能kinetic energy接触(滑移)能contact(sliding) energy沙漏能houglass energy系统阻尼能system damping energy刚性墙能量rigidwall energyGLSTAT 中报告的弹簧阻尼能”Spring and damper energy”是离散单元(discrete elements)、安全带单元(seatbelt elements)内能及和铰链刚度相关的内能(*constrained_joint_stiffness…)之和。

而内能”InternalEnergy”包含弹簧阻尼能”Spring and damper energy”和所有其它单元的内能。

因此弹簧阻尼能”Spring anddamper energy”是内能”Internal energy”的子集。

由SMP 5434a 版输出到glstat 文件中的铰链内能”joint internal energy”跟*constrained_joing_stiffness 不相关。

它似乎与*constrained_joint_revolute(_spherical,etc)的罚值刚度相关连。

这是SMP 5434a 之前版本都存在的缺失的能量项，对MPP 5434a 也一样。

这种现象在用拉格朗日乘子(Lagrange Multiplier)方程时不会出现。

与*constrained_joint_stiffness 相关的能量出现在jntforc 文件中，也包含在glstat 文件中的弹簧和阻尼能和内能中。

回想弹簧阻尼能”spring and damper energy”，不管是从铰链刚度还是从离散单元而来，总是包含在内能里面。

在MATSUM 文件中能量值是按一个part 一个part 的输出的(参见*database_matsum)。

LS-DYNA的学习方法

第三就是要熟读关键字手册，理论手册。虽然英文的看起来很吃力，但这些最原始的资料的可信度是最高的。
Hale Waihona Puke 第四就是多做实例，做之前用自己的理论知识来预测结果。用DYNA计算之后与理论及实验结果对比，找出产生差别原因。最后修改K文件，细心体会总结K文件改动后对计算结果的影响。
使用LS-Dyna已经有两年多了，在国内的许多的论坛也摸爬滚打了很久，感觉资源还是很少。后来直接访问了LSTC的网站和相关的资源，受益菲浅。
LS-DYNA的学习方法\
2008年12月02日星期二下午 09:56学习LS-DYNA可以先看基本参考书，第一本推荐时党勇老师的，写的很详细，特别适合初学者。然后可以看看白金泽，尚晓江的。反正基本市面上出的书，我都争取买一本，因为一共也没几本。
另外学LS-DYNA不可舍本逐末，软件的熟练应用只是次要的。最主要的知识还是弹塑性力学、流体力学、有限元，一定要打下坚实基础（我就没打好基础，唉）。
现在觉得LS-Dyna为何应用如此广泛，一点非常重要的就是相应的网络资源的开放，特别用户会议的成功开放。光dynalook,Dyna-more就有很多非常有价值的论文资料，和国内的相关的网站比，资源要丰富的多。特别是许多的国外的用户论文价值还是很高的，在一些行业应用领域很有参考价值。
而且，比较而言，国外的东西搞得还是比较通俗易懂的，包括理论部分，甚至老外会把很多细节的实现都写的清清楚楚。我们国内的参考文献则不是。所以，我最大的心得就是参照一些国外的资源。

LS-dyna 常见问题汇总2.0

LS-DYNA 常见问题汇总 2.0
资料整理：yuminhust2005 职务：A2:LS-DYNA 版主资料来源：网络和自己的总结更新时间：2008-10-12
LS-DYNA 常见问题汇总 2.0
yuminhust2005
2008-10...................................................................................................................................................1 2. 单位制度 .................................................................................................................................................................5 3. 质量缩放 .................................................................................................................................................................6 4. 长分析时间 .............................................................................................................................................................7 5. 准静态 .....................................................................................................................................................................8 6. 计算不稳定 .............................................................................................................................................................9 7. 负体积 ...................................................................................................................................................................10 8. 能量平衡 ...............................................................................................................................................................11 9. 沙漏控制 ...............................................................................................................................................................13 10. 阻尼 ...................................................................................................................................................................14

LS-DYNA常见问题及解决策略 (2012年11月7日)

LS‐DYNA求解器
支持单机和并行计算支持Windows、Unix、Linux等系统有32位、64位版本有单精度、双精度版本
LS‐DYNA求解器
2011/11/9
13
2011/11/9
14
湖南大学汽车车身先进设计制造国家重点实验室
LS‐DYNA基础
湖南大学汽车车身先进设计制造国家重点实验室
HGEN Hourglass energy calculation option. This option requires significant additional storage and increases cost by ten percent: EQ.1: hourglass energy is not computed (default), EQ.2: hourglass energy is computed and included in the energy balance.
2011/11/9
31
2011/11/9
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湖南大学汽车车身先进设计制造国家重点实验室
Hourglass LS‐DYNA沙漏控制方法
湖南大学汽车车身先进设计制造国家重点实验室
Hourglass LS‐DYNA沙漏控制方法沙漏控制系数
IHQ=1，2，3：粘性控制模式，用于高速 IHQ=4，5，6：刚性控制模式，用于低速 IHQ=8：仅用于16号壳单元
2011/11/9
软件特点
LS‐DYNA是功能齐全的几何非线性（大位移、大转动和大应变）、材料非线性（160多种材料动态模型）和接触非线性（40多种接触类型）程序它以Lagrange算法为主，兼有ALE和Euler算法以显式求解为主，兼有隐式求解功能以结构分析为主，兼有热分析、流体‐结构耦合功能以非线性动力分析为主，兼有静力分析功能（如动力分析前的预应力计算和薄板冲压成形后的回弹计算）

dyna中K关键字整理

一，Supported LS-DYNA KeywordsThe following gathers the supported keywords and their syntax for Explicit Dynamics (LS-DYNA Export) systems. The exported keyword file follows the same format as the corresponding Mechanical APDL application. Keywords conform to the “LS_DYNA Keyword User’s Manual” versions 970 and 971 (version 971 has particular features for the handling of beam cross section and integration options).Each keyword consists of one or more cards, each with one of more parameters. If a parameter is not shown, it will be assigned default values by the LS-DYNA solver. In addition some descriptions to Workbench features that do not relate directly to keywords are given at the end of this section, entitled General Descriptions.1，*BOUNDARY_NON_REFLECTINGSpecifies impedance boundaries. Impedance boundaries can only be applied on solid elements in LS-DYNA.Card∙SSID = ID of segment on whose nodes the boundary is applied (see *SET_SEGMENT bellow).∙AD = 0.0 (default) for setting the activation flag for dilatational waves to on.∙AS = 0.0 (default) for setting the activation flag for shear waves to on.2，*BOUNDARY_PRESCRIBED_MOTION_NODE_IDSee *BOUNDARY_PRESCRIBED_MOTION_SET3，*BOUNDARY_PRESCRIBED_MOTION_RIGID_IDSee *BOUNDARY_PRESCRIBED_MOTION_SET4，*BOUNDARY_PRESCRIBED_MOTION_SET_IDSpecifies velocity and displacement boundary conditions.Card required for keyword option ID.∙ID = ID of the prescribed motion keyword. This parameter is optional and does not have to be unique. An index number is added.∙HEADING = Name of the specific boundary condition load. The name is taken from the caption of the applied velocity or displacementin the tree outline of the Mechanical application.Card1∙ID = ID of set of nodes or part (for rigid bodies) to which the boundary condition is applied.∙DOF = 1, 2 or 3 depending whether the boundary condition is in the x, y or z direction respectively. Setting 4 is used if the boundaryis applied according to a local coordinate system.∙VAD = 0 or 2 depending whether the boundary condition is velocity or displacement.∙LCID = ID of the curve prescribing the magnitude of the boundary condition. Constant values of velocity are applied as a stepfunction from time = 0. Constant values of displacement are ramped from zero at time = 0 to the constant value at termination time.This is done to make sure that displacements are applied in atransient fashion.∙SF = 1.0 (default) scale factor for load curve.∙VID = 0 (default). ID of vector that defines the local coordinate system the boundary condition is applied with.∙DEATH = 0.0 (default), sets it to 1E28.∙BIRTH = 0, the motion is applied from the beginning of the solution. Card2: not required.5，*BOUNDARY_SPC_SETSpecifies Fixed Support, Simple Support and Fixed Rotation constraints. Card∙NSID = ID of set of nodes to which the boundary is applied.∙CID = ID of the associated coordinate system. 0 specifies the global coordinate system.∙DOFX = 0 or 1 for free or fixed translation, respectively, along the x direction. It is set to 0 for Fixed Rotation and to 1 otherwise.∙DOFY = 0 or 1 for free or fixed translation, respectively, along the y direction. It is set to 0 for Fixed Rotation and to 1 otherwise.∙DOFZ = 0 or 1 for free or fixed translation, respectively, along the z direction. It is set to 0 for Fixed Rotation and to 1 otherwise.∙DOFRX = 0 or 1 for free or fixed translation, respectively, along the x direction. It is set to 0 for Simple Support and to 1 otherwise.∙DOFRY = 0 or 1 for free or fixed translation, respectively, along the y direction. It is set to 0 for Simple Support and to 1 otherwise.∙DOFRZ = 0 or 1 for free or fixed translation, respectively, along the z direction.. It is set to 0 for Simple Support and to 1otherwise.6，*CONSTRAINED_RIGID_BODIESSpecifies rigid bodies to be merged into one part. The resulting Part ID matches the ID of the rigid body designated as the master.This keyword is created for rigid bodies which belong to the same multibody part. By constraining the rigid bodies together using a single multibody part you avoid specifying conflicting motion on the nodes shared among the rigid bodies. All boundary conditions applied to the master body will also be applied to all the slaves. Any boundary conditions that were applied to the slaves will be ignored.The body that is selected to be master is the first one that appears in the multibody-part list.Card∙PIDM = ID of the master rigid body.∙PIDS = ID of the slave rigid body.7，*CONSTRAINED_SPOTWELDSpecifies spot welds between non-contiguous nodal pairs of shell elements. This keyword is created when a spot weld contact is defined in the Mechanical application.Card∙N1 = ID of the first node used in the weld.∙N2 = ID of the second node present in the weld.∙SN = Normal force at weld failure.∙SS = Shear force at weld failure.∙N = Exponent of normal force.∙M = Exponent of shear force.8，*CONTACT_AUTOMATIC_GENERALSpecifies friction or frictionless contacts between line bodies (beams). This keyword is created if the contact is specified using Body Interactions and the geometry contains line bodies.All the parameter cards are the same as in*CONTACT_AUTOMATIC_SINGLE_SURFACE.9，*CONTACT_AUTOMATIC_NODES_TO_SURFACESpecifies nodes-to-surface friction or frictionless contacts. This keyword is created if the contact is specified using a Contact Region and the Behavior is set to Asymmetric.Card1 - mandatory∙SSID = ID for the set of slave nodes involved in the contact.∙MSID = ID for the set of master segments involved in the contact.∙SSTYP = 4, the slave entities for the contact are nodes.∙MSTYP = 0, the master entities for the contact are segments.∙SBOXID, MBOXID, SPR and MPR are the same as in*CONTACT_AUTOMATIC_SINGLE_SURFACE.Parameter Card2 and Card3 is the same as in*CONTACT_AUTOMATIC_SINGLE_SURFACE.10，*CONTACT_AUTOMATIC_SINGLE_SURFACESpecifies friction or frictionless contacts between parts. This keyword is created if the contact is specified using Body Interactions.Card1 - mandatory∙SSID = ID for the set of parts created for the bodies in the Body Interaction. If the contact is applied to all the bodies in the geometry then this parameter is set to 0.∙MSID = 0.∙SSTYP =2, the slave entities are parts. If the contact is applied to all the bodies in the geometry then this parameter is set to 5.∙MSTYP = 2, the master entities are parts. If the contact is applied to all the bodies in the geometry then this parameter is set to 0.∙SBOXID = It is not used, will be left blank.∙MBOXID = It is not used, will be left blank.∙SPR = 1 (constant) requests that forces on the slave side of the contact be included in the results files NCFORC (ASCII) and INTFOR(binary). These two results files are not currently specified in the exported K file and are not created. The user will need tomanually specify the *DATABASE_NCFORC and *DATABASE_BINARY_INTFORkeywords to obtain them.∙MPR = 1 (constant) requests that forces on the master side of the contact be included in the results files NCFORC (ASCII) and INTFOR(binary). These two results files are not currently specified inthe exported K file and are not created. The user will need tomanually specify the *DATABASE_NCFORC and *DATABASE_BINARY_INTFORkeywords to obtain them.Card2 - mandatory∙FS = Friction Coefficient value from the inputs for frictional contact.∙FD = Dynamic Coefficient value from the inputs for frictional contact.∙DC = Decay Constant value from the inputs for frictional contact.∙VC = 0 (LS-DYNA default).∙VDC = 10 (constant). This parameter specifies the percentage of the critical viscous damping coefficient to be used in order to avoidundesirable oscillation in the contact.Card3 - mandatory, left blank for defaults to be used.Card A is the same as for *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE. 11，*CONTACT_AUTOMATIC_SURFACE_TO_SURFACEDefines specific surface-to-surface friction or frictionless contacts. This keyword is created if the contact is specified using a Contact Region and the Behavior is set to Symmetric.Card1 - mandatory∙SSID = ID for the set of slave segments involved in the contact.∙MSID = ID for the set of master segments involved in the contact.∙SSTYP = 0, the slave entities for the contact are segments.∙MSTYP = 0, the master entities for the contact are segments.∙SBOXID, MBOXID, SPR and MPR are the same as in*CONTACT_AUTOMATIC_SINGLE_SURFACE.Parameter Card2 and Card3 are the same as in*CONTACT_AUTOMATIC_SINGLE_SURFACE.Card A∙SOFT = 2 except for asymmetric contacts like NODES_TO_SURFACE and unbreakable bonded contacts for which it is set to 1.∙• SOFSCL = left blank, the default value of 0.1 will be used. This scale factor is used to determine the stiffness of the interfacewhen SOFT is set to 1. For SOFT = 2 scale factor SLSFAC (see*CONTROL_CONTACT) is used instead.∙LCIDAB = left blank.∙MAXPAR= left blank.∙SBOPT = 3.∙DEPTH = 5.12，*CONTACT_AUTOMATIC_SURFACE_TO_SURFACE_TIEBREAKSpecifies breakable symmetric bonded contacts. This keyword is created for Bonded contact when the Breakable option is set to Stress Criteria and the contact Behavior is set to Symmetric.Card 1 is the same as in *CONTACT_TIED_SURFACE_TO_SURFACE_OFFSET.Card2 - mandatory∙FS = Normal Stress Limit value for the bonded contact.∙FD = Shear Stress Limit value for the bonded contact.∙DC = 0 (LS-DYNA default). This parameter is not required for bonded contacts.∙VC and VDC are the same as in *CONTACT_AUTOMATIC_SINGLE_SURFACE. Card3 - mandatory, is left blank.Card A is the same as for *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE. 13，*CONTACT_ONEWAY_AUTOMATIC_SURFACE_TO_SURFACE_ TIEBREAKSpecifies breakable asymmetric bonded contacts. This keyword is created for Bonded contact when the Breakable option is set to Stress Criteria and the contact Behavior is set to Asymmetric.Parameter cards are the same as in*CONTACT_AUTOMATIC_SURFACE_TO_SURFACE_TIEBREAK.Card A is not used for this keyword.14，*CONTACT_TIED_NODES_TO_SURFACE_OFFSETSpecifies non breakable asymmetric bonded contacts. This keyword is created for Bonded contacts that are not designated as Breakable whose Behavior is set to Asymmetric. This keyword is not used for Body Interactions as these types of contacts are always symmetric.Card1 - mandatory∙SSID = ID for the set of slave nodes involved in the contact.∙MSID = ID for the set of master segment or for the set of parts involved in the contact.∙SSTYP = 4. SSID indicates the ID for a set of nodes.∙MSTYP = 0, MSID indicates the ID for a set of segments.∙SBOXID, MBOXID, SPR and MPR are the same as in*CONTACT_AUTOMATIC_SINGLE_SURFACE.Card 2 left blank.Card 3∙SFS = left blank, the default value of 1.0 will be used. Default slave penalty stiffness scale factor for SLSFAC (see*CONTROL_CONTACT).∙SFM= left blank, the default value of 1.0 will be used. Default master penalty stiffness scale factor for SLSFAC (see*CONTROL_CONTACT).∙SST = the negative value of:"Maximum Offset" is the Definition parameter available for bondedcontacts and body interactions. "Maximum Offset" is obtained fromthe inputs of the Contact Region of Bonded type.∙MST = SST.15，*CONTACT_TIED_SURFACE_TO_SURFACE_OFFSETSpecifies general non-breakable bonded contacts that are symmetric. This keyword is created for Bonded and non-breakable contacts which are defined by Contact Regions that are Bonded, non-breakable and whose Behavior is set to Symmetric.Card1 - mandatory∙SSID = ID for a set of slave segments or a set of parts involved in the contact.∙MSID = ID for the set of master segments or the set of parts involved in the contact..∙SSTYP = specifies whether the ID used in SSID represents parts or segments. It is set to 0 if SSID represents a set of segments and2 if it represents a set of parts.∙MSTYP = SSTYP.∙SBOXID, MBOXID, SPR and MPR are the same as in*CONTACT_AUTOMATIC_SINGLE_SURFACE.Cards 2 and 3 are the same as in *CONTACT_TIED_NODES_TO_SURFACE_OFFSET. Card A is the same as for *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE. 16，*CONTROL_ACCURACYSpecifies control parameters that can improve the accuracy of the calculation.Card∙OSU = 1. Global flag for objective stress updates. Required for parts that undergo large rotations. When set to 1 the flag is on.∙INN = 4. Invariant node numbering for shell and solid elements. When set to 4 the flag is on for both shell and solid elements. 17，*CONTROL_BULK_VISCOSITYSets the bulk viscosity coefficients globally.Card∙Q1 = Quadratic Artificial Viscosity from the "Damping Controls" in the Analysis Settings.∙Q2 = Linear Artificial Viscosity from the "Damping Controls" in the Analysis settings.∙TYPE = -2. Internal energy dissipated by the viscosity in the shell elements is computed and included in the overall energy balance. 18，*CONTROL_CONTACTSpecifies the defaults for computations of contact surfaces.Card 1∙SLSFAC = 0 (default). Scale factor for sliding interface penalties.When set to 0 the value used is 0.1. This scale factor together withthe SFS and SFM parameters of the individual contact keyword (seeCard 3 of *CONTACT_TIED_NODES_TO_SURFACE_OFFSET) is used todetermine the stiffness of the interface when SOFT is set to 2 (seeCard A of *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE).∙RWPNAL = 0 (there is no default value). Scale factor for rigid wall penalties. When equal to 0 the constrain method is used and nodalpoints which belong to rigid bodies are not considered.∙ISLCHK = 1 (default). Initial penetration check in contact surfaces.When set to 1 there is no checking.∙SHLTHK = 1 (default). Shell thickness considered in surface to surface and node to surface contact types. When set to 1, thicknessis considered but rigid bodies are excluded.∙PENOPT = 1 (default). Penalty stiffness value option.∙THKCHG = 0 (default).∙ORIEN = 2. Automatic reorientation for contact segments during initialization. When set to 2 it is active for manual (segment) and automated (part) input.∙ENMASS = 0 if the Retain Inertia Of Eroded Material option of the Erosion Controls in the Details window of the analysis settings is set to No.= 2 (default) if Retain Inertia Of Eroded Material option of the Erosion Controls in the Details view of the analysis settings is set to Yes.This parameter regulates the treatment of the mass for eroded nodes in contact. When set to 0 eroding nodes are removed from thecalculation.Card 2∙USRSTR = 0. Storage per contact interface for user supplied interface control subroutine. When set to 0 no input data is read and no interface storage is permitted in the user subroutine.∙Default values are used for all other parameters.Card3∙SFRIC = 0. Default static coefficient of friction.∙Default values are used for all other parameters.Card4∙IGNORE = 2. Specifies whether to ignore initial penetrations in the *CONTACT_AUTOMATIC options. When set to 2 initial penetrations are allowed to exist by tracking them. Also warning messages are printed with the original and the recommended coordinates of each slave node.∙FRCENG = 0 (default).∙SKIPRWG = 0 (default).∙OUTSEG = 1. Yes, output each beam spot weld slave node and its master segment for *CONTACT_SPOTWELD into D3HSP file.∙SPOTSTP = 0 (default).∙SPOTDEL = 1.Yes, delete the attached spot weld element if the nodes of a spot weld beam or solid element are attached to a shell element that fails and the nodes are deleted.∙SPOTHIN = 0.5. This factor can be used to scale the thickness of parts within the vicinity of the spot weld. This factor helps avertpremature weld failures due to contact of the welded parts with theweld itself. Should be greater than zero and less than one. 19，*CONTROL_ENERGYSpecifies the controls for energy dissipation options.Card∙HGEN = 2. Hourglass energy is computed and included in the energy balance. Results are reported in ASCII files GLSTAT and MATSUM.∙RWEN = 2 (default).∙SLNTEN = 2. Sliding interface energy dissipation is computed and included in the energy balance. Results are reported in ASCII filesGLSTAT and SLEOUT.∙RYLEN = 2. Rayleigh energy dissipation is computed and included in the energy balance. Results are reported in ASCII file GLSTAT. 20，*CONTROL_HOURGLASSSpecifies the global hourglass parameters.Card∙IHQ = 1 if Hourglass Damping of type Standard is selected in the Analysis Settings. Also this parameter is equal to 1 if the Flanagan Belytschko option is selected but both the coefficients are zero.= 5 if the Flanagan Belytschko option is selected and the Stiffness Coefficient is non-zero.= 3 if the Flanagan Belytschko option is selected, the Stiffness Coefficient is zero and the Hex Integration Type of the SolverControls is set to Exact.= 2 if the Flanagan Belytschko option is selected, the Stiffness Coefficient is zero and the Hex Integration Type of the SolverControls is set to 1pt Gauss.∙QH = Viscous Coefficient of the Hourglass Damping section of the Analysis Settings if IHQ is equal to 1, 2, or 3.= Stiffness Coefficient if IHQ is 5.21，*CONTROL_SHELLSpecifies global parameters for shell element types.Card∙WRPANG = 20 (default).∙ESORT = 1, full automatic sorting of triangular shell elements to treat degenerate quadrilateral shell elements as C0 triangularshells.∙IRNXX = -2, shell normal update option. When set to -2 unique nodal fibers are incrementally updated based on the nodal rotation at the location of the fiber.∙ISTUPD = 4, shell thickness update option for deformable shells.Membrane strains cause changes in thickness in 3 and 4 node shell elements, however elastic strains are neglected. This option is very important in sheet metal forming or whenever membranestretching is important. For crash analysis, setting 4 may improve energy conservation and stability.∙THEORY = 2 (default). Belytschko-Tsay formulation.∙BWC = 1 if Shell BWC Warp Correction option is set to Yes in the Solver Controls section of the Analysis Settings. For this setting, Belytschko-Wong-Chiang warping stiffness is added.= 2 if Shell BWC Warp Correction option is set to No.∙MITER = 1 (default). Plane stress plasticity: iterative with 3 secant iterations.∙PROJ = 1, the full projection method is used for the warping stiffness in the Belytschko-Tsay and Belytschko-Wong-Chiang shell elements. This option is required for explicit calculations. 22，*CONTROL_SOLIDSpecifies global parameters for solid element types.Card∙ESORT = 1, full automatic sorting of tetrahedron and pentahedron elements to treat degeneracies. Degenerate tetrahedrons will be treated as ELFORM = 10 and pentahedron as ELFORM = 15 solidsrespectively (see *SECTION_SOLID).23，*CONTROL_TERMINATIONSpecifies the termination criteria for the solver.Card∙ENDTIM = End Time in the Step Controls section of the Analysis Settings.∙ENDCYC = Maximum Time Steps of the Step Controls section of the Analysis Settings.∙DTMIN = 0.01 (constant).∙ENDENG = Maximum Energy Error from the Step Controls section of the Analysis Settings.∙ENDMAS = Maximum Part Scaling from the Step Controls section of the Analysis Settings, if Automatic Mass Scaling is set to Yes.If Automatic Mass Scaling is set to No, the default value of 0.0 is used.24，*CONTROL_TIMESTEPSpecifies conditions for determining the computational time step. Card∙DTINIT = Initial Time Step from the Step Controls section of the Analysis Settings.∙TSSFAC = Time Step Safety Factor from the Step Controls section of the Analysis Settings.∙ISDO = 0 (default). Basis of time size calculation for 4-node shell elements.∙TSLIMT = Minimum Element Timestep from the Erosion Controls section of the Analysis Settings, if On Minimum Element Timestep is set to Yes. If On Minimum Element Timestep is set to No the default value of 0.0 is used.∙DT2MS = the negative value of Minimum CFL Timestep specified in the Step Controls section of the Analysis Settings, if Automatic Mass Scaling is set to Yes. If Automatic Mass Scaling is set to No the default value of 0.0 is used.∙LCTM = ID of the load curve which uses Maximum Time Step from the Step Controls section of the Analysis Settings.∙ERODE = 1 (constant).∙MS1ST = 0 (default).25，*DAMPING_GLOBALSpecifies the mass weighted nodal damping applied globally to the nodes of deformable bodies and the center of mass of rigid bodies.Card∙LCID = 0, a constant damping factor will be used as specified in VALDMP.∙VALDMP = Static Damping from the Damping Controls section of the Analysis Settings.26，*DATABASE_BINARY_D3PLOTSpecifies the sampling parameters for the binary D3PLOT results plotting file.Card∙DT = Time from the Output Controls section of the Analysis Settings if Save Results on is set to Time.= End Time divided by the Number of Points if Save Results On is set to Equally Spaced Time Points.27，*DATABASE_BINARY_RUNRSFSpecifies the sampling parameters for the RUNRSF restart file.Card∙CYCL = Time Steps from the Output Controls section of the Analysis Settings if Save Restart Files on is set to Time Steps.= Maximum Time Steps divided by the Number of Points if Save Results On is set to Equally Spaced Time Points.28，*DATABASE_ELOUTSpecifies the sampling parameters for the ELOUT results file (stores stress and strain results).Card∙DT = (see *DATABASE_BINARY_D3PLOT).29，*DATABASE_FORMATSpecifies the format in which to write binary results files like D3PLOT and D3THDT.Card∙IFORM = 0, binary results will be written only in the LS-DYNA format. 30，*DATABASE_GLSTATSpecifies the sampling parameters for the GLSTAT results file (stores general energy results).Card∙DT = (see *DATABASE_BINARY_D3PLOT).31，*DATABASE_MATSUMSpecifies the sampling parameters for the MATSUM results file (stores general energy and velocity results as the GLSTAT file but it stores them per body. It is necessary for rigid bodies).Card∙DT = (see *DATABASE_BINARY_D3PLOT).32，*DATABASE_NODOUTSpecifies the sampling parameters for the NODOUT results file (stores displacement and velocity results).Card∙DT = (see *DATABASE_BINARY_D3PLOT).33，*DEFINE_COORDINATE_SYSTEMSpecifies a local coordinate system with three points: one at the local origin, one on the local x-axis and one on the local x-y plane.Card1∙CID = ID of the coordinate system, must be unique.∙XO = global X-coordinate of the origin.∙YO = global Y-coordinate of the origin.∙ZO = global Z-coordinate of the origin.∙XL = global X-coordinate of a point on the local x-axis.∙YL = global Y-coordinate of a point on the local x-axis.∙ZL = global Z-coordinate of a point on the local x-axis.Card2∙XP = global X-coordinate of a point on the local x-y plane.∙YP = global Y-coordinate of a point on the local x-y plane.∙ZP = global Z-coordinate of a point on the local x-y plane. 34，*DEFINE_CURVESpecifies magnitudes that are given in tabular format. Some keywords require magnitudes to be specified as a load curve. Should a constant be needed, it may be represented as a curve by repeating its value for time steps 0 and 1.Card1∙LCID = ID for load curve, is incremented every time a new load curve is defined.Card2, 3, 4...∙ A = abscissa value, usually time.∙O = ordinate (function) value.35，*DEFINE_VECTORSpecifies a vector by defining the coordinates of two points. This keyword defines the local coordinate system with respect to which a*BOUNDARY_PRESCRIBED_MOTION is prescribed. The ID of this coordinate system is specified with parameter CID.Card∙VID = ID of the vector.∙XT = 0, the local x-coordinate of the origin of the coordinate system specified with CID below.∙YT = 0, the local y-coordinate of the origin of the coordinate system specified with CID below.∙ZT = 0, the local z-coordinate of the origin of the coordinate system specified with CID below.∙XH = 1 if the vector has a component in the x direction of the coordinate system specified with CID. Otherwise, this is set to 0.∙YH = 1 if the vector has a component in the x direction of the coordinate system specified with CID. Otherwise, this is set to 0.∙ZH = 1 if the vector has a component in the x direction of the coordinate system specified with CID. Otherwise, this is set to 0.∙CID = ID of the coordinate system used to define the vector. If no coordinate system is specified this parameter is set to 0 to specify the global coordinate system.36，*ELEMENT_BEAMSpecifies beam elements.Card∙EID = ID of the element.∙PID = ID of the part it belongs to.∙N1 = ID of nodal point 1.∙N2 = ID of nodal point 2.∙N3 = ID of nodal point 3, used for cross section orientation. 37，*ELEMENT_SHELLSpecifies three, four, six and eight noded shell elements.Card∙EID = ID of the element.∙PID = ID of the part it belongs to.∙N1 = ID of nodal point 1.∙N2 = ID of nodal point 2.∙N3 = ID of nodal point 3.∙N4 = ID of nodal point 4.∙N5-8 = ID of mid side nodes for six and eight noded shells. 38，*ELEMENT_SOLIDSpecifies 3D solid elements including 10-noded tetrahedrons (second order). Apart from the second order case the two cards are combined into one.Card1∙EID = ID of the element.∙PID = ID of the part it belongs to.Card2∙N1 = ID of nodal point 1.∙N2 = ID of nodal point 2.∙N3 = ID of nodal point 3.∙N4 = ID of nodal point 4.∙.∙.∙.∙N10 = ID of nodal point 10.39，*ENDTerminates the keyword file. It has no parameter cards.二，Equation Of State (EOS) keywordsThe following are descriptions for *EOS keywords natively supported by the LS-DYNA export feature. More generally, any *EOS keyword may be introduced into the export file with the help of Commands objects in the Mechanical application (termed Keyword Snippet when referring to the LS-DYNA solver). To use it, insert a Keyword Snippet under a Geometry body in the Tree Outline. The program will automatically substitute the EOSID parameter, in accordance with the *PART keyword (see below) of the associated body. All other parameters in the Keyword Snippet are transcribed literally, overriding any values that would otherwise derive from the Engineering Data workspace.If the *EOS keyword is entered in a Keyword Snippet anywhere else in the Tree Outline, it will be exported literally and the Engineering Data EOS information will also be exported, if present. This practice is not recommended, however, and a warning is provided in the header of Keyword Snippet objects when detected.1，*EOS_GRUNEISENSpecifies a shock equation of state. This keyword is created when a Shock EOS linear equation of state is present in the properties of a material that is used in the simulation and the Johnson Cook plasticity model is also present. The bilinear version of this equation of state is not currently supported.Card1∙EOSID = ID of the keyword, must be unique between the *EOS keywords.∙ C = parameter C1 for a Linear Shock EOS property.∙S1 = parameter S1 for a Linear Shock EOS property.∙S2 = Parameter Quadratic S2 for a Linear Shock EOS property.∙S3 = 0.∙GAMAO = Gruneisen Coefficient for a Linear Shock EOS property.∙ A = 0.Card2 - mandatory, left blank.2，*EOS_LINEAR_POLYNOMIAL。

LS-DYNA使用指南第五章

LS-DYNA使用指南第五章2007-11-29 作者：安世亚太点击进入论坛第五章求解特性5.1求解过程当模型建好后（即，单元、实常数、材料性质的定义，建立模型、网格划分、边界/初始条件指定以及加载、结束控制），执行SOLVE命令即可以开始求解过程。

（在GUI中，菜单路径为Main Menu>Solution>Solve）。

此时，ANSYS/LS-DYNA程序将运行以下几步：1.标题记录：包括几何特性（如节点和单元等），都写到相应的两个结果文件Jobname.RST和Jobname.HIS中。

（此时ANSYS/LS-DYNA数据库中包含全部相应的信息。

即在运行SOLVE命令前，必须执行SAVE命令，把所有的模型信息都写入到文件Jobname.DB）。

2.将所有输入的信息写出LS-DYNA程序的输入文件Jobname.K 。

3.控制权由ANSYS程序转移给LS-DYNA程序。

LS-DYNA求解器运行的结果写入到结果文件Jobname.RST和Jobname.HIS中。

如果执行SOLVE命令前给定命令EDOPT，ADD，，BOTH，则也将输出用于LS-POST后处理程序的结果文件（d3plot和d3thdt文件）。

当求解结束后，ANSYS/LS-DYNA GUI将提醒用户求解已完成，控制权重新转回到ANSYS/LS-DYNA程序。

可以通过ANSYS/LS-DYNA程序的POST1和POST26后处理器来查看结果。

如果产生了错误或警告，输出窗口将自动显示弹出信息，表明有几个错误和警告。

可以参考LS-DYNA的信息文件，其中详细记录了错误和警告。

这些信息也同时被写入到LS-DYNA d3hsp文件。

5.2 LS-DYNA终止控制LS-DYNA求解终止点与建模时设定的终止控制有关。

主要有以下几种终止控制类型：·终止时间-用T IME命令定义分析结束时间。

时间步累积达到结束时间时计算就会停止。

LS_DYNA软件个人学习总结

LS_DYNA软件个人学习总结1、单位制：在DYNA动力学分析软件中，我们一般使用的单位制为(mm、mg、ms)。

即：mm mg ms m/s mN kpa g/cm3 mJ2、在DYNA中我们涉及到接触时，一般选择自动单面接触，次接触自动判断接触部分，如果为壳单元此接触自动考虑壳后，因此在建模时，注意留有间隙。

此外，对于单面接触，程序不会输出界面力，需要设置一个力的传感器*CONTACT_FORCE_TRANSDUCER_PENALTY 来定义，将从面设置为你所需要得到接触力的部件，一般只用定义一下ssid（salve set id)， sstyp(salve set type)，同时在用*DATBASE_RCFORC来输出。

就可以得到了接触力了。

此方法一般用来输出接触力以及刚体所受反力。

3、关键字*mat_add_erosion注意：excl为排除关键字，这个数字可以任意定义，如果某个参数对应的失效准则与此相同，则此准则就会被忽略。

几乎所有的力学软件都有统一规定：静水压以压为正、拉为负；所以对于静水压破坏准则就是给出最大静水压应力，如果大于该值，则材料破坏。

相反，应力则是以拉为正，压为负，所以拉应力破坏准则就是给出最大拉应力，如果拉应力大于该值，则材料破坏。

4、输出损伤变量3、LS-DYNA求解中途退出的解决方案LS-DYNA在求解过程中由于模型的各种问题常发生中途退出的问题，归纳起来一般有三种现象：一是单元负体积，二是节点速度无限大，三是程序崩溃。

单元负体积：这主要是由于人工时间步长设置的不合理，调小人工时间步长可解决该问题。

还有就是材料参数和单元公式的选择合理问题。

节点速度无限大：一般是由于材料等参数的单位不一致引起，在建立模型时应注意单位的统一，另外还有接触问题，若本该发生接触的地方没有定义接触，在计算过程中可能会产生节点速度无限大。

程序崩溃：该现象不常发生，若发生，首先检查硬盘空间是否已满，二是检查求解的规模是否超过程序的规模。

LS-DYNA求解过程中常见错误和警告信息

错误名称
原因及修改措施
输入格式不正确
找到错误位置，修改数据格式
浮点溢出，核心代码崩溃
(1)材料和单元特性定义错误，如零密度、零厚度等
(2)单元定义错误
(3)各种曲线定义有问题，如求解时间比定义曲线的时间不稳定
程序一开始就崩溃
(1)单位不一致
(3)太高的局部接触力，需调整间隙、降低接触刚度或降低时间步
错误名称原因及修改措施输入格式不正确找到错误位置修改数据格式浮点溢出核心代码崩溃1材料和单元特性定义错误如零密度零厚度等2单元定义错误3各种曲线定义有问题如求解时间比定义曲线的时间长导致数据外推失效4单位不一致5时间步太大导致求解不稳定程序一开始就崩溃1单位不一致2边界条件荷载曲线定义错误3某一材料未定义节点速度无限大1应用lsprepost检查最后一帧动画找出崩溃的单元和part2part的材料定义有问题如某个参数设置过大或与该part相关的接触定义有问题检查接触的设置负体积1材料参数设置错误选择合适材料模式2沙漏模式的变形积累改为全积分单元3太高的局部接触力需调整间隙降低接触刚度或降低时间步
(2)边界条件、荷载曲线定义错误
(3)某一材料未定义
节点速度无限大
(1)应用LS-PREPOST检查最后一帧动画，找出崩溃的单元和PART
(2)PART的材料定义有问题，如某个参数设置过大或与该PART相关的接触定义有问题，检查接触的设置
负体积
(1)材料参数设置错误，选择合适材料模式
(2)沙漏模式的变形积累，改为全积分单元

ls-dyna修改k文件总结

ls-dyna修改k文件总结
各种前处理软件得到的k文件往往不能满足使用要求，或者存在一些错误，这时就要自己修改、添加关键字
下面是自己总结的几条：
0. k文件格式分为标准格式和自由格式（数据之间用逗号隔开）两种，在一个k 文件中，两种方式可以并存，但是在一个数据卡中，只能选择一种方式
1. 如果选择标准格式：k文件中除了节点（node）和单元（element）关键字外，通常每一行总共占80个字符长度，每个数据占10个字符长度，修改时千万不要超越这10个字符长度的位置，也不要跑到别的数据的10个字符位置
2. 如果关键字手册里的card介绍中没有提到optional，那么每一行card都不能省略，哪怕它们都是0
3. 为了方便查看10个字符长度，可以用ultraedit软件
4. 每一个关键字必须以*开头，并且必须顶格写
5. 在k文件中$后面的是注释，求解时不考虑
6. 为了查找和发现具体是那一关键字出错，可以使用lspost打开k文件，然后选择view选项查看。

LS-dyna 常见问题汇总1.0

LS-DYNA常见问题汇总1.0资料来源：网络和自己的总结yuminhust2005Copyright of original English version owned by relative author. Chinese version owned by /Kevin目录1.Consistent system of units 单位制度 (2)2.Mass Scaling 质量缩放 (4)3.Long run times 长分析时间 (9)4.Quasi-static 准静态 (11)5.Instability 计算不稳定 (14)6.Negative Volume 负体积 (17)7.Energy balance 能量平衡 (20)8.Hourglass control 沙漏控制 (27)9.Damping 阻尼 (32)10.ASCII output for MPP via binout (37)11.Contact Overview 接触概述 (41)12.Contact Soft 1 接触Soft=1 (45)13.LS-DYNA中夹层板(sandwich)的模拟 (47)14. 怎样进行二次开发 (50)1.Consistent system of units 单位制度相信做仿真分析的人第一个需要明确的就是一致单位系统(Consistent Units)。

计算机只认识0&1、只懂得玩数字，它才不管你用的数字的物理意义。

而工程师自己负责单位制的统一，否则计算出来的结果没有意义，不幸的是大多数老师在教有限元数值计算时似乎没有提到这一点。

见下面LS-DYNA FAQ中的定义：Definition of a consistent system of units (required for LS-DYNA):1 force unit = 1 mass unit * 1 acceleration unit1 力单位＝1 质量单位× 1 加速度单位1 acceleration unit = 1 length unit / (1 time unit)^21 加速度单位= 1 长度单位/1 时间单位的平方The following table provides examples of consistent systems of units.As points of reference, the mass density and Young‘s Modulus of steel are provided in each system of units. ―GRA VITY‖ is gravitational acceleration.2.Mass Scaling 质量缩放质量缩放指的是通过增加非物理的质量到结构上从而获得大的显式时间步的技术。

LS DYNA 批处理

！！！Dyna批处理！！！我都是自己编辑批处理来进行计算的，比ansys的好，我自己觉得，虽然不算高科技，总有人不知道，贴出来大家看看吧，具体办法如下：1、设置环境变量。

右键单击‘我的电脑’，选属性----高级-----环境变量，找到path变量，在变量值（很长很长）的最后添加一个分号‘;’，然后查找你的ansys安装目录下一个叫ls970的文件，找到之后把路径复制下来，拷贝到刚才分号的后面，确定再确定，设置环境变量的目的是使系统认识ls970命令在什么地方；环境变量设置成功与否，可这样检验，在运行里面键入ls970，回车，有窗口调出就行了。

2、编辑批处理文件。

在你ansys工作目录（就是你要进行dyna计算的目录）新建文本文件，将后缀名从txt改变为bat，中间会询问你是否改变后缀名，是！！！右键单击之，选择编辑，出现空白的编辑界面：情况A：你只想进行某一个单独的计算，只需要在批处理文件中键入ls970 i=jobname.k保存，然后令批处理文件与k文件同目录，双击批处理，计算开始！！！情况B：想进行系列计算，新建足够多空的文件夹，每个里面放一个你想计算的k文件，在这些空文件夹上一级目录同样建一个上述的批处理文件，进行如下编辑cd D:\ansyswork\dyna1ls970 i=jobname.kcd D:\ansyswork\dyna2ls970 i=jobname.kcd D:\ansyswork\dyna3ls970 i=jobname.k........上面的路径和k文件名根据自己的重新设置，保存，双击批处理，就等着吧，你的k文件就会一个一个接着算啦！在批处理文件里也是可以设置使用的cpu数量的。

比如，在后面加上ncpu=2，则可以利用两个cpu进行并行计算，以此类推。

当然这需要license的支持。

同时打开几个k文件同时计算与一次利用多个cpu进行依次计算的效率会多少有点区别。

让UltraEdit更好的编辑LS-Dyna的Key文件

让UltraEdit更好的编辑LS-Dyna的Key文件在平时工作中，经常会因为各类CAE前处理器(eg.Patran,FEMB,HyperMesh)无法完全支持求解器的所有特性而必需手工添加或者修改卡片。

而进行卡片修改或添加时我使用最多的就是UltraEdit(Windows Platform)和Vim(Linux Platform下)。

因为这两种编辑器均支持自定义语法高亮显示，而且新版本还支持Folding功能，所以合理设置后可以大大增加Keyword 文件的可读性。

下面就先以UltraEdit进行LS-Dyna的Key文件进行编辑为例介绍一下我的设置方法，以期与大家交流和分享。

1.所需要UltraEdit的版本Version<11.XX 经过设置，则能高亮显示各keyword，并可以在Function List里列出key 文件里所包含的大部分Keyword,双击即可以到达指定位置。

Version>=11.xx 经过设置可以利用新版本的Folding功能，将部分Keyword折叠起来，更方便进行文件的浏览。

2.对应不同版本所需要相应做的修改Version<11.xx将下面的部分添加到UltraEdit安装目录的wordfile.txt文件里面---------------------Begin----------------------------------/L6"LS-Dyna" Line Comment = $ Nocase File Extensions = KEY K/Function String = "%[*][A-DG-JL-Z]*"/C1** CONTROL_ AIRBAG_ ALE_ BOUNDARY_ COMPONENT_ CONSTRAINED_ CONTACT_CONTROL_ DAMPING_ DATABASE_ DEFINE_ DEFORMABLE_TO_RIGID ELEMENT_ EOS_HOURGLASS INCLUDE INITIAL_ INTEGRATION_ INTERFACE_ LOAD_ MAT_ NODEPARAMETER PART RAIL_ RIGIDWALL_ SECTION_ SET_ TERMINATION_ TITLE TRANSLATE_ USER_ STRESS_ KEYWORD END----------------------End-----------------------------------注意：上面的"/L6"要根据实际的wordlist.txt里面已经有的语言种类数进行适当修改经过上面修改，则在打开.key or .k为扩展名的LS-Dyna计算文件时，会自动高亮显示Keyword；在View->Views/Lists->Function List则可以在右边以列表的形式显示大部分的Keyword.Version>=11.xx因高于11.xx的版本支持Folding功能，所以通过添加标识为Folding的关键字可以更好的显示Key文件。

一、关于起爆点设置的问题：ls-dyna中是通过点来定义起爆的，即关键字

一、关于起爆点设置的问题：LS-DYNA中是通过点来定义起爆的，即关键字*INITIAL_DETONTION，解释一下下面card 的意思，第一个PID，定义炸药的ID，EQ:-1，考虑声学边界，可参考注释中的公式，详细可查看关键字手册；EQ:0，考虑所有炸药。

下面三个数据定义点坐标X,Y,Z的值，LT定义起爆时间。

如果考虑声学边界，则要用到第二个card。

下面纠正一个错误，一直以来很多人都认为设置两个起爆点即为线起爆，这种说法并不准确，k手册中并没有提及到线或面起爆，只是通过点来定义起爆的，因此，定义两个点就叫做线起爆是不对的，从另一个方面分析：线起爆只能通过多个点来近似模拟，并不是真正意义上的线起爆。

关于线起爆的说法，在时老师的书中提到过，在一个例子中，说是采用中心线起爆，设置了两个起爆点。

这个问题我问过时老师，设置两个起爆点就说是线起爆是不准确的，线起爆可以通过多点近似模拟，并不能真正实现线起爆。

所以ls_dyna中只能说是点起爆或者是多点起爆。

补充一下，如果不设置起爆点，则系统会默认为考虑所有炸药同时起爆，下面是一个简单的例子，例子中未设置起爆点，K文件中包含3个part，part1、2为炸药，part3为空气，均采用共节点。

为方便计算，采用“准二维”方式建模，即z轴只有一个单元的厚度。

二、流固耦合流固耦合用以处理流体和结构相互作用的问题，说白了，就是ALE（或者Euler）和lagrange 单元间的耦合。

论坛中有中说法:流固耦合有三种方法,共节点法,接触法,和真正意义上的流固耦合,我觉得这种说法是不准确的,下面解释一下,流固耦合最明显的特征就是在建立模型时,流体和结构(固体)之间必须有重合部分，一般是流体的网格包含结构的网格，举例说明一下，如时党勇一书中,炸药在土壤中的爆炸一例,炸药、土壤、空气、和混凝土板，前三个定义为ALE（流体）单元，混凝土板定义为LAG单元，流体网格包含结构网格，也就是流体和固体之间有重合的网格。

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