上海仿坤发布MPDB_V1.0
该模型是上海仿坤软件科技有限公司（LSDYNA-China)基于LSTC (Livermore Software Technology Corporation)公司发布的版本号为LSTC.MPDB.190409_V2.0的MPDB模型基础上改进而来。
此模型在LSTC.MPDB.190409_V2.0 基础上主要改进工作是通过在MPDB的BLOCK B上添加30个可以漏气的气囊(关键字为*AIRBAG_SIMPLE_AIRBAG_MODEL_ID)，以此来考虑壁障在碰撞过程中壁障内部的空气没有及时排除，而引起的蜂窝腔内的气体压力升高这一物理现象。同时调整了BLOCK B蜂窝处的材料曲线，使其动态性能满足相应法规要求。
公司网址：www.lsdyna-china.com
联系邮箱地址：feamodel@lsdyna-china.com
联系电话：021-61261195 4008533856
1、版本历史
Fangkun.MPDB. V1.0
基于LSTC (Livermore Software Technology Corporation)公司发布的版本号为LSTC.MPDB.190409_V2.0的MPDB模型基础上改进而来。为上海仿坤软件科技有限公司发布的第一个版本
在MPDB的BLOCK B上添加30个可以漏气的气囊(关键字为*AIRBAG_SIMPLE_AIRBAG_MODEL_ID)，以此来考虑壁障在碰撞过程中壁障内部的空气没有及时排除，而引起的蜂窝腔内的气体压力升高这一物理现象。
相比LSTC.MPDB.190409_V2.0调整了BLOCK B 蜂窝处的材料曲线
推荐使用R7 或者更高版本
该MPDB模型的力vs 变形响应在Euro_NCAP_MPDB (文件号 TB022, 发布于2017年10月23日)所述的通道内
因此，本MPDB模型与物理测试结果基本一致
其他细节描述详见LSTC.MPDB.190409_V2.0文档，本模型其他细节与其所述的细节一致。
文件构成：
发布的模型文件夹内有三个和计算相关的模型文件Main_MPDB_Assembly_10.k、mat_sec_curve.asc、MPDB.Main.Rigid.Tube.k ，其中mat_sec_curve.asc为加密文件，已通过*include被Main_MPDB_Assembly_10.k引用。
MPDB已有地面刚性墙，用户不需要另建MPDB的地面刚性墙
*CONTROL_TIMESTEP里有选择质量缩放，请勿关掉（参数IMSCL）
*CONTROL_SHELL中ISTUPD为4
set_part ID 19或1为MPDB与整车接触的所有part（19为MPDB模型所有PART集合，1为除后面小车的其他所有PART集合），请使用该ID设置与整车的接触。与整车之间的接触请使用*CONTACT_AUTOMATIC_SURFACE_TO_SURFACE（注意不要包含任何整车的一维单元，否则速度会很慢）。
MPDB模型的ID号范围为1-600,000
整车模型请include Main_MPDB_Assembly_10.k .
2、单位
模型单位为mm-ms-kg-kN .
3、模型描述
图1、BLOCK B 添加30个气囊
在LSTC公司的LSTC.MPDB.190409_V2.0模型基础上进行改进：BLOCK B处添加了30个考虑漏气的气囊，由壳单元划分，气囊所用关键字为*AIRBAG_SIMPLE_AIRBAG_MODEL_ID，气囊通过*CONSTRAINED_NODAL_RIGID_BODY与BLOCK B的前后板进行连接。
整体模型信息：厚壳单元数量: 24526 ，壳单元数量: 502053，节点数量：353077，梁单元数量: 11069 ，时间步长: 6.3e-4 ms。由于模型其他细节均与LSTC.MPDB.190409_V2.0一致，详见附录A.
图2、30个气囊的整体尺寸
4、结果&验证
A. Rigid Tubular Impactor
图3、力vs变形变化图 [不同DT2MS的值]
由上图可以看出，本模型采用不同的DT2MS值(每个值填入LS-DYNA中为负值)，其结果都在法规要求的边界通道内，且基本一致。
5、本MPDB模型整车应用案例
图4、前面板变形仿真与试验对比图
图5、壁障小车加速度仿真与试验对比图
1
附录 A –壁障LSTC.MPDB.190409_V2.0的介绍摘录
由于本模型的其他细节与壁障LSTC.MPDB.190409_V2.0完全一致，其他介绍请参考下文：
• (1)BARRIER BLOCK DIMENSIONS AND DESCRIPTION
Oblique View and Dimensions of Mobile Progressive Deformable Barrier
Figure 1 – Barrier Block Oblique View
Side View of Mobile Progressive Deformable Barrier
Figure 2 barrier block side view
Mobile Progressive Deformable Barrier Construction
Figure 3 – PDB Construction
Barrier Block Construction
The Mobile Progressive Deformable Barrier is broadly partitioned into three deformable honeycomb cores.
The front and the rear cores are homogeneous and have constant crush strength, when crushed statically.
The middle core offers a progressive crush resistance through its depth of 450 mm.
The quasi-static test procedure to evaluate the strength of the middle core is discussed in the reference document provided with this package+.
Figure 4 – Barrier Block
+TB-022-euro-ncap-mobile-progressive-deformable-barrier-face-specification-
Figure 5 – Crush strength specification for different cores
Cladding and Plate Construction
The three blocks comprising the Mobile Progressive Deformable Barrier are separated by aluminum plates, as shown in the following figure.
Further, the blocks are bonded to the plates through epoxy resin which is modeled by employing spotweld beams characterized by *MAT_SPOTWELD, with appropriate failure parameters (forces) in axial and shear directions.
The barrier blocks are contained by an outer cladding along three directions and a back plate in one direction.
Figure 6 – Cladding and Plate Construction
• (2)BARRIER AND CART DIMENSIONS
A. Cart for Rigid Tubular Impactor
Figure7 – Rigid Tube Impactor and Cart – Side View
Figure 8 – Rigid Tube Impactor and Cart – Top View
• (3)IMPACTOR CONSTRUCTION
A. Rigid Tube Impactor
B.1.Impactor Shape
Figure 9 – Impactor Shape
B.2.Impactor Features
Impact Velocity = 60 kph [16.667 m/s]
B.3.Impactor Mounted on Cart
Figure 10 – Impactor and Cart Weight
B.4.Impactor Dimensions, Overlap and Test Procedure
The impactor overlaps the barrier by 800 mm along its width, as shown in the following figure:
Figure 11 – Impactor Overlap along width
The impactor overlaps the barrier by 400 mm along the height of the barrier, as shown in the following figure:
Figure 12 – Impactor Overlap along height
