Blastwave Hitting A Bunker

Chapter 43: Blastwave Hitting a Bunker

43

Blastwave Hitting a Bunker



Summary



Introduction



Solution Requirements



Results



Pre- and Postprocess with SimXpert



Input File(s)

736 737 737

739

797

743

736 MD Demonstration Problems CHAPTER 43

Summary Title

Chapter 43: Blastwave Hitting a Bunker

Contact features

• Fast Coupling Technique • Multiple Eulerian Domains with failure • Free flow between two euler zones on the side faces of bunker • Explosive modeled by ideal gas

Geometry

Euler Zone 2 Euler Zone 1

Bunker

Blast

Ground

Material properties

• Bunker Structure Density = .000734 lbf-s2/inch4 Young’s Modulus = 2.9E7 lbf/in2 Poisson’s ratio = 0.3 Yield stress = 5.E4 lbf/in2 Plastic strain at failure = 0.21 • Euler (Air) Density = 1.2E-7 lbf-s2/inch4 Gamma = 1.4 Specific Internal Energy = 3E+8 lbf-in • Euler (Explosive - equivalent to TNT of 7kg and radius of .25 meter) Density = 3.84E-6 lbf-s2/inch4 Specific Internal Energy = 3E+9 lbf-in • Ground Rigid

Analysis characteristics

Transient explicit dynamic analysis (SOL 700)

Boundary conditions

• Fixed boundary condition of ground • In and out directional flow boundary of outer euler zone

Element types

• 4-node shell element for bunker and ground • 8-node hex element for euler which is automatically generated by MESH option

FE results

1. Isosuface plot of Specific Internal Energy (SIE) at 0.01 seconds 2. Deformed Effective Stress plot at 0.01 seconds

CHAPTER 43 737 Blastwave Hitting a Bunker

Introduction The purpose is to demonstrate application of multi-Euler domains to failing coupling surfaces. The problem simulates a bunker, located on the ground that is open at the sides and is surrounded by air. Gas can flow freely through the sides of the bunker. A blast wave is ignited close to the bunker and expands into the air. When by the impact of the blast wave, the bunker surface fails gas will flow trough the bunker surface.

Solution Requirements SOL 700 Modeling The bunker and the ground consist of cquad4 shell elements. The elements of the bunker are Lagrangian deformable shells and the ground is modeled as rigid, using a MATRIG. The explosive/air region is modeled by two Euler meshes. The first domain models the inside of the bunker, and the second one models the outside of the bunker. For the interaction between the bunker and an Euler domain, a unique coupling surface has to be used, therefore, two coupling surfaces are needed. The first coupling surface, for modeling the inside of the bunker, consists of the following facets: • The 180 degrees cylindrical surface and the two open sides of the bunker. The two open sides are represented by dummy shell elements. These are elements 1 to 2240. • The top of the ground that lies within the bunker. This is a square and is formed by elements 2241 to 3280. These facets make up a closed coupling surface, as shown in Figure 43-1. This coupling surface contains gas inside, and therefore Euler elements outside the coupling surface should not be processed and so the COVER is OUTSIDE.

738 MD Demonstration Problems CHAPTER 43

Figure 43-1

Coupling Surface 1

The second coupling surface consists of the following facets: • The 180 degrees cylindrical surface and the two open sides of the bunker. These are elements 1 to 2240. The top of the ground inside the bunker is not part of the second COUPLE. • The top of the ground that is outside the bunker and 5 dummy surfaces of the ground that are used to close the coupling surfaces. These are formed by the elements 3413 to 4012, 4095 to 4340, 4505 to 4709, 4894 to 7904. These facets make up a closed coupling surface, as shown in Figure 43-2.

Figure 43-2

Coupling Surface 2

This coupling surface is used for simulating the gas outside the coupling surface. So Euler elements inside the coupling surface should not be processed and the COVER has to be set to INSIDE. The second coupling surface uses the second Euler mesh and serves as inner boundary surface for this Euler mesh. The outside boundary of this mesh is where the Euler domains ends and boundary conditions for this boundaries are provided by a FLOWDEF. The FLOWDEF is chosen as non-reflecting. Waves exit the Euler domain with only little reflection.

CHAPTER 43 739 Blastwave Hitting a Bunker

To get an accurate expansion of the blast wave, the diffusion should be kept at a minimum, and therefore the Roe solver with second-order is used. Interactive failure will be used for the bunker structure, while porosity will be used for the open sides: • The bunker elements can fail and gas flows through the failed elements from outside the bunker into the bunker. All elements of the bunker are assigned to a BSURF, and occur in both coupling surfaces. They are able to fail interactively, using the COUP1FL entry. These parts are formed by elements 1 to 1600. The nodes of the failed elements are constrained in space by using PARAM, NZEROVEL, YES, to preserve the geometry of the coupling surfaces from severe distortion. • Since gas can flow through the two sides without any obstruction, these two areas are modeled with BSURF entries, and are opened by using a PORFLCPL entry. These sides are modeled with dummy shell elements and consist of elements 1601 to 2400. The couple cards refer to mesh-number. The first mesh for the Euler elements inside the bunker is created and initialized by: PEULER1,301,,2ndOrder,111

MESH,2,BOX,,,,,,,+ +,-430.,0.,-1287.,837.,480.,1296.,,,+ +,24,16,30,,,,EULER,301 The value “2ndOrder” activates the Roe solver with second-order accuracy. The property id is the link between the TICEUL1 entry 101 and the MESH entry. The second Euler mesh for the Euler elements outside the bunker is created and initialized by: PEULER1,201,,2ndOrder,101

MESH,1,BOX,,,,,,,+ +,-647.,0.,-1293.,1057.,447.,1293.,,,+ +,33,23,37,,,,EULER,201

Results Figures 43-3 and 43-4 show a fringe plot and an isosurface. Figure 43-4 has been created by Ensight.

Figure 43-3

Deformed Effective Stress Plot of the Bunker

740 MD Demonstration Problems CHAPTER 43

Figure 43-4

Isosurfaces Created using SIE Variable for the Two Euler Domains

Abbreviated SOL 700 Input File SOL 700,NLTRAN STOP=1 CEND TITLE= Job name is: bunker IC=1 SPC=1 TSTEPNL=1 $ BEGIN BULK $------- BULK DATA SECTION ------$ $INCLUDE mesh.dat INCLUDE model.dat $ TSTEPNL 1 20 0.0005 1 $------- Parameter Section -----DYPARAM,FASTCOUP,,FAIL PARAM*,DYINISTEP,1E-7 PARAM*,DYMINSTEP,1E-8 DYPARAM,LIMITER,ROE DYPARAM,RKSCHEME,3 DYPARAM,LSDYNA,BINARY,D3PLOT,0.002 $ $ ========== PROPERTY SETS ========== $ $ * steel prop * $ PSHELL 1 1 .150 $ $ * dummy_shell * $ PSHELL,2,2,1E-3 MATD009,2,1E-20 $

CHAPTER 43 741 Blastwave Hitting a Bunker

$ PSHELL 3 4 .100 $ $ ========= MATERIAL DEFINITIONS ========== $ $ $ -------- Material steel id =1 MATD024,1,.000734,2.9e+07,.3,50000,,.21 $ $ -------- Material AIR id =3 MATDEUL 3 1.2e-07 3 EOSGAM 3 1.4 $ $ -------- ground MATRIG 4 .000734 2.9e+07 .3 $ $ ======== Load Cases ======================== $ $ ------- General Coupling: GENERAL ----$ $ COUPLE 7 1 INSIDE ON ON + + 1 1 $ BSURF 1 1 THRU 2240 3413 + THRU 4340 4505 THRU 4709 $ $ COUP1FL,1,1.2e-07,3e+08 $ COUPLE 8 11 OUTSIDE ON ON + + 2 2 $ BSURF 11 1 THRU 3280 $ $ COUP1FL,2,1.2e-07,3e+08 $ $ COUPINT,1,7,8 $ PORFCPL,81,LARGE,,BOTH,8 LEAKAGE,1,16,32,PORFCPL,81,,1.0 BSURF 32 1601 THRU 2240 $ $ ------- Rigid Body Constraints ----$ SPCD2 1 RIGID MR4 1 0 1 SPCD2 1 RIGID MR4 2 0 1 SPCD2 1 RIGID MR4 3 0 1 SPCD2 1 RIGID MR4 5 0 1 SPCD2 1 RIGID MR4 6 0 1

16

+ +

THRU 4894

4012 THRU

4095+ 7904

+ +

0. 0. 0. 0. 0.

742 MD Demonstration Problems CHAPTER 43

SPCD2 1 RIGID MR4 7 0 1 TABLED1 1 + 0. 1. 1. 1. ENDT $ $-----Mesh.dat--------------$ MESH,1,BOX,,,,,,,+ +,-647.,0.,-1293.,1057.,447.,1293.,,,+ +,33,23,37,,,,EULER,201 $ $ Inner Euler $ MESH,2,BOX,,,,,,,+ +,-430.,0.,-1287.,837.,480.,1296.,,,+ +,24,16,30,,,,EULER,301 $ PEULER1,201,,2ndOrder,101 PEULER1,301,,2ndOrder,111 $ $ TICEUL1 101 101 TICREG 1 101 SPHERE 8 3 TICREG 2 101 SPHERE 5 3 4 $ SPHERE 8 -536.4 165 -453.6 SPHERE 5 -536.4 165 -453.6 $ $ TICEUL1 111 111 TICREG 3 111 SPHERE 9 3 $ SPHERE 9 -53.4 100 -673.6 $ $ $ ------- TICVAL BC AIR-INI ----TICVAL 4 DENSITY 1.2e-07 SIE $ $ ------- TICVAL BC EXP-INI ----TICVAL 5 DENSITY3.84e-06 SIE $ $ FLOWDEF,202,,HYDRO,,,,,,+ +,FLOW,BOTH $ ENDDATA

0. +

5

2 1

85 10000

4 10000

3e+08 3e+09

1

CHAPTER 43 743 Blastwave Hitting a Bunker

Pre- and Postprocess with SimXpert This example shows how to use SimXpert for a blast wave hitting a bunker shell. The two open sides are each modeled by a fully porous subsurface using PORFCPL The flow of gas through failed shell elements is taken into account by activating interactive failure.

For simulations with coupling surfaces with failure, the Roe solver is used. The second-order Roe solver is used to minimize the diffusion of the blast wave. Two types of result files are required: • ARC which includes the Euler element results • d3plot which includes the Lagrangian element results

Run SimXpert with MD Explicit Workspace a. For Default Workspace:, select MD Explicit

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744 MD Demonstration Problems CHAPTER 43

Import the Model Data a. File: select Import b. Select Nastran c. Select model.dat, click Open d. The model is imported into the Model Browser

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CHAPTER 43 745 Blastwave Hitting a Bunker

Create Equation of State (Ideal Gas) a. Materials and Properties tab: EOS b. Select [12] EOS Ideal Gas c. For Name enter EOSGAM_3 d. For PID enter 3 e. For GAMMA enter 1.4 f. Click Create g. New EOS is added

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746 MD Demonstration Problems CHAPTER 43

Create Flow Boundary a. LBCs tab: Flow b. Select FLOWDEF c. For ID: enter 202 d. For Title: enter FLOWDEF_202 e. Click FLOW; select BOTH f. Click Modify g. New FLOWFED is added

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CHAPTER 43 747 Blastwave Hitting a Bunker

Create Transient Initial Condition for Euler (Air) a. LBCs tab: TIC b. Select TICVAL c. For ID: enter 4 d. For Title: enter TICVAL_4 e. Click DENSITY; enter 1.2E-07 f. Click SIE; enter 3.0E+08 g. Click Modify h. TICVAL_4 is added

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748 MD Demonstration Problems CHAPTER 43

Create Transient Initial Condition for Euler (TNT) (continued) a. LBCs tab: TIC b. Select TICVAL c. For ID: enter 5 d. For Title: enter TICVAL_5 e. Click DENSITY; enter 3.84E-6 f. Click SIE; enter 3.0E+09 g. Click Modify h. TICVAL_5 is added

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CHAPTER 43 749 Blastwave Hitting a Bunker

Create Sphere Shape for TNT a. LBCs tab: Sphere b. From the Pick Window: select XYZ c. For X,Y,Z Coordinate, enter -536.4, 165.0, -453.6; click OK d. For ID, enter 8 e. For Title, enter Sphere_8 f. For RADIUS, enter 85.0 g. Click Modify h. Sphere_8 is added

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750 MD Demonstration Problems CHAPTER 43

Create Sphere Shape for Outside Air (continued) a. LBCs tab: Sphere b. From the Pick Window: select XYZ c. For X,Y,Z Coordinate, enter -536.4, 165.0, -453.6; click OK d. For ID, enter 5 e. For Title, enter Sphere_5 f. For RADIUS, enter 10000.0 g. Click Modify h. Shpere_5 is added

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CHAPTER 43 751 Blastwave Hitting a Bunker

Create Sphere Shape for Inside Air (continued) a. LBCs tab: Sphere b. From the Pick Window: select XYZ c. For X,Y,Z Coordinate, enter -53.4, 100.0, -673.6; click OK d. For ID, enter 9 e. For Title, enter Sphere_9 f. For RADIUS, enter 10000.0 g. Click Modify h. Sphere_9 is added

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752 MD Demonstration Problems CHAPTER 43

Create Euler Material a. Materials and Properties tab: Eulerian b. Select Eulerian Material c. For Name, enter MATDEUL_3 d. For MID, enter 3 e. For RHO, enter 1.2e-7 f. Double click EID, select Select g. For Entity Selection, select EOSGAM_3; click OK h. Click Create i. MATDEUL_3 is added

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CHAPTER 43 753 Blastwave Hitting a Bunker

Create Transient Initial Value for TNT a. LBCs tab: TIC b. Select TICREG c. For ID, enter 1 d. For Title, enter TICREG_1 e. Activate TYPE f. Double click VID, select Select g. For Entity Selection, select Sphere_8; click OK h. Activate and double click MID, select Select i. For Entity Selection, select MATDEUL_3; click OK j. Activate and double click TICID, select Select k. For Entity Selection, select TICVAL_5; click OK l. For LEVEL, enter 2 m. Click Modify n. TICREG_1 is added

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754 MD Demonstration Problems CHAPTER 43

Create Transient Initial Value for Outer Air (continued) a. LBCs tab: TIC b. Select TICREG c. For ID, enter 2 d. For Title, enter TICREG_2 e. Activate TYPE f. Double click VID, select Select g. For Entity Selection, select Sphere_5; click OK h. Activate and double click MID, select Select i. For Entity Selection, select MATDEUL_3; click OK j. Activate and double click TICID, select Select k. For Entity Selection, select TICVAL_4; click OK l. For LEVEL, enter 1 m. Click Modify n. TICREG_2 is added

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CHAPTER 43 755 Blastwave Hitting a Bunker

Create Transient Initial Value for Inner Air (continued) a. LBCs tab: TIC b. Select TICREG c. For ID, enter 3 d. For Title, enter TICREG_3 e. Activate TYPE f. Double click VID, select Select g. For Entity Selection, select Sphere_9; click OK h. Activate and double click MID, select Select i. For Entity Selection, select MATDEUL_3; click OK j. Activate and double click TICID, select Select k. For Entity Selection, select TICVAL_4; click OK l. For LEVEL, enter 1 m. Click Modify n. TICREG_3 is added

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756 MD Demonstration Problems CHAPTER 43

Create Transient Initial Value Conditions of Eulerian Zone a. LBCs tab: TIC b. Select TICEUL1 c. For ID, enter 101 d. For Title, enter TICEUL1_101 e.For NREG, enter 101 f. Click Modify g. TICEUL1_101 is added

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CHAPTER 43 757 Blastwave Hitting a Bunker

Create Transient Initial Conditions of Eulerian Zone (continued) Modify the Transient Initial Condition a. Double click TICEUL1_101 b. Double click TSID1, select Select c. For Entity Selection, select TICREG_1; click OK d. Double click TSID2, select Select e. For Entity Selection, select TICREG_2; click OK f. Click Modify

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758 MD Demonstration Problems CHAPTER 43

Create Transient Initial Conditions of Eulerian Zone (continued) a. LBCs tab: TIC b. Select TICEUL1 c. For ID, enter 111 d. For Title, enter TICEUL1_111 e. For NREG, enter 1 f. Click Modify f. TICEUL1_111 is added

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CHAPTER 43 759 Blastwave Hitting a Bunker

Create Transient Initial Conditions of Eulerian Zone (continued) a. Double click TICEUL1_111 b. Double click TSID1; select Select c. For Entity Selection, select TICREG_3; click OK d. Click Modify

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760 MD Demonstration Problems CHAPTER 43

Create Eulerian Property a. Materials and Properties tab: 3D b. Select PEULER1 c. For Name, enter PEULER_201 d. For PID, select 201 e. For TYPE, select 2ndOrder f. Double click SID, select Select g. For Entity Selection, select TICEUL1_101; click OK h. Click Create i. PEULER1_201 is added

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CHAPTER 43 761 Blastwave Hitting a Bunker

Create Eulerian Property (continued) a. For Name, enter PEULER_301 b. For PID, select 301 c. For TYPE, select 2ndOrder d. Double click SID, select Select e. For Entity Selection, select TICEUL1_111; click OK f. Click Create g. PEULER1_301 is added

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762 MD Demonstration Problems CHAPTER 43

Create Mesh for Outer Euler a. LBCs tab: Eulerian b. Select Mesh c. For TYPE, select BOX d. Deactivate DXVEL through ZREF e. For XO, enter -647.0; for YO, enter 0.0; for ZO, enter -1293.0 f. For DX, enter 1057.0; for DY, enter 447.0; for DZ, enter 1293.0 g. For NX, enter 33; for NY, enter 23; for NZ, enter 37 h. For PROP, select EULER i. Double click PID, select Select j. For Entity Selection, select PEULER1_201; click OK k. Click Modify l. Mesh_1 is added

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CHAPTER 43 763 Blastwave Hitting a Bunker

Create Mesh for Inner Euler a. LBCs tab: Eulerian b. Select Mesh c. For TYPE, select BOX d. Deactivate DXVEL through ZREF e. For XO, enter -430.0; for YO, enter 0.0; for ZO, enter -1287.0 f. For DX, enter 837.0; for DY, enter 480.0; for DZ, enter 1296.0 g. For NX, enter 24; for NY, enter 26; for NZ, enter 30 h. For PROP, select EULER i. Double click PID, select Select j. For Entity Selection, select PEULER1_201; click OK k. Click Modify l. Mesh_2 is added

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764 MD Demonstration Problems CHAPTER 43

Create Coupling for Outer Coupling Surface Failure a. LBCs tab: Couple b. Select COUP1FL c. For ID, enter 1 d. For Title, enter COUP1FL_1 e. For RHO, enter 1.2E-07 f. For SIE, enter 3.0E+08 g. Deactivate XVEL, YVEL, ZVEL, PRESSURE, and MATERIAL h. Click Modify i. COUP1FL_1 is added

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CHAPTER 43 765 Blastwave Hitting a Bunker

Create Coupling for Inner Coupling Surface Failure a. LBCs tab: Couple b. Select COUP1FL c. For ID, enter 2 d. For Title, enter COUP1FL_2 e. For RHO, enter 1.2E-07 f. For SIE, enter 3.0E+08 g. Deactivate XVEL, YVEL, ZVEL, PRESSURE, and MATERIAL h. Click Modify i. COUP1FL_2 is added

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766 MD Demonstration Problems CHAPTER 43

Create Group for Outer Coupling Surface a. Right click on the Model Browser tree, select New b. Select Group, select Create c. For Pick entities: deactivate Pick nodes and Pick Part options d. In Main window, select all elements e. In Group window for Add/Remove Content, click Add to group f. Under Member list, see that all elements are added g. Click OK

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CHAPTER 43 767 Blastwave Hitting a Bunker

Create Group for Outer Coupling Surface (continued) a. In the Model Browser tree, select PSHELL_1_model.dat and PSHELL_2_model.dat b. Select Hide c. From the Ribbon menu: select Advanced Pick Dialog d. In Extended Pick Dialog, select Contiguous [Auto] e. Select the inside part of the base plates f. In Group window for Add/Remove Content, click Remove from Group g. Under Member list, see that assigned elements are removed h. Click OK

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Useful Tip! If using Show Selection List option, the elements selected are shown in Selected Items dialog

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768 MD Demonstration Problems CHAPTER 43

Create Group for Inner Coupling Surface a. Right click on the Model Browser tree, select New b. Select Group, select Create c. From the Ribbon menu: select Advanced Pick Dialog d. In Extended Pick Dialog, select Contiguous [Auto] e. Select the inside part of the base plates f. In Group window for Add/Remove Content, click Add to group g. Under Member list, see that all elements are added

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CHAPTER 43 769 Blastwave Hitting a Bunker

Create Group for Inner Coupling Surface (continued) a. In the Model Browser tree, select PSHELL_1_model.dat and PSHELL_2_model.dat b. Select Show Only c. In the Main Window: select all the elements d. In Group window for Add/Remove Content, click Add to group e. Under Member list, see that all elements are added f. Total in the Member list should now be 3280 g. Click OK

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770 MD Demonstration Problems CHAPTER 43

Create Inner Coupling Surface a. In the Model Browser tree, select GROUP_2 b. Select Show Only c. LBCs tab: Couple d. From the Pick Window: select Shells for BSURF e. In the Main Window: select all the elements f. Click Done

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CHAPTER 43 771 Blastwave Hitting a Bunker

Create Inner Coupling Surface (continued) a. For ID, enter 8 b. For Title, enter COUPLE_8 c. For COVER, select: OUTSIDE d. Activate REVERSE and CHECK e. Activate and double click MID, select Select f. For Entity Selection, select Mesh_2; click OK g. Activate and double click COUP1FL, select Select h. For Entity Selection, select COUP1FL_2; click OK i. Click Modify

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772 MD Demonstration Problems CHAPTER 43

Create Porosity a. LBCs tab: Accessory b. Select PORFCPL c. For ID, enter 81 d. For Title, enter PORFCPL_81 e. For SIZE, select LARGE f. Activate FLOW, select BOTH g. Activate and double click COUP1FL, select Select h. For Entity Selection, select COUPLE_8; click OK i. Click Modify

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CHAPTER 43 773 Blastwave Hitting a Bunker

Create Leakage a. In the Model Browser tree, select PSHELL_2_model.dat b. Select Show Only c. LBCs tab: Accessory d. Select LEAKAGE e. From the Pick Window: select Shells for BSURF f. In the Main Window: select all the elements g. Click Done h. For ID, enter 1 i. For Title, enter LEAKAGE_1 j. For NPOR, enter 1 k. Click Modify

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774 MD Demonstration Problems CHAPTER 43

Modify Leakage a. In the Model Browser tree, double click LEAKAGE_1 b. Double click SUBID1 c. For Entity Selection, select BSURF_4; click OK d. For PORTYPE1, select PORFCPL e. Double click PORTYPID1, select Select f. For Entity Selection, select PORFCPL_81; click OK g. Activate COEFF1, select CONSTANT h. Activate COEFFV1, enter 1.0 i. Click Modify

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CHAPTER 43 775 Blastwave Hitting a Bunker

Create Outer Coupling Surface a. In the Model Browser tree, select Group_1 b. Select Show Only c. LBCs tab: COUPLE d. From the Pick Window: select Shells for BSURF e. In the Main Window: select all the elements f. Click Done

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776 MD Demonstration Problems CHAPTER 43

Create Outer Coupling Surface (continued) a. For ID, enter 7 b. For Title, enter COUPLE_7 c. For COVER, select: INSIDE d. Activate REVERSE and CHECK e. Activate and double click PORID, select Select f. For Entity Selection, select LEAKAGE_1; click OK g. Activate and double click COUP1FL, select Select h. For Entity Selection, select COUP1FL_1; click OK i. Click Modify

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CHAPTER 43 777 Blastwave Hitting a Bunker

Create Coupling Surface Interaction a. LBCs tab: Couple b. Select COUPINT c. For ID, enter 1 d. For Title, enter COUPINTL_1 e. Double click CID1, select Select f. For Entity Selection, select COUPLE_7; click OK g. Double click CID2, select Select h. For Entity Selection, select COUPLE_8; click OK i. Click Modify

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778 MD Demonstration Problems CHAPTER 43

Create Boundary Condition a. In the Model Browser tree, select PSHELL_1_model.dat and PSHELL_2_model.dat b. Select Hide c. LBCs tab: LBC d. Select SPC BC and select Fully Fixed Constraint e. From the Pick Window: select Nodes f. In the Main Window: select all the nodes g. Click Done

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CHAPTER 43 779 Blastwave Hitting a Bunker

Create Parameters a. Job Parameters tab: PARAM b. For Name, enter PARAM_1 c. For SID, enter 1 d. For N, enter DYINISTEP e. For V1, enter 1.E-7 f. Click Create g. For Name, enter PARAM_2 h. For SID, enter 2 i. For N, enter DYMINSTEP j. For V1, enter 1.E-8 k. Click Create

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780 MD Demonstration Problems CHAPTER 43

Create Parameters (continued) a. Job Parameters tab: DYPARAM b. For Name, enter DYPARAM_1 c. For SID, enter 1 d. For F1, enter FASTCOUP e. For F3, enter FAIL f. Click Create g. For Name, enter DYPARAM_2 h. For SID, enter 2 i. For F1, enter LIMITER j. For F2, enter ROE k. Click Create l. For Name, enter DYPARAM_2 m. For SID, enter 2 n. For F1, enter RKSCHEME o. For F2, enter 3 p. Click Create

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CHAPTER 43 781 Blastwave Hitting a Bunker

Create Parameters (continued) a. Job Parameters tab: DYPARAM_BINARY_option b. For Name, enter DYPARAM_BINARY_option_3 c. For SID, enter 3 d. Activate DT_D3PL, enter 0.002 e. Click Create

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782 MD Demonstration Problems CHAPTER 43

Create New SOL700 Job a. In the Model Browser tree, right click model.dat b. Select Create new Nastran job c. For Solver Input File, change the input file name and location d. Click OK

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CHAPTER 43 783 Blastwave Hitting a Bunker

Create New SOL700 Job (continued) a. In the Model Browser tree, right click Loadcase Control b. Select Properties c. Select Subcase Nonlinear Static Parameters d. For Ending Time, enter 0.01 e. For Number of Time Steps, enter 10 f. Click Apply g. Click Close

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784 MD Demonstration Problems CHAPTER 43

Execute the Job a. In the Model Browser tree, right click NewJob b. Click Run

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CHAPTER 43 785 Blastwave Hitting a Bunker

Attach the Analysis Results File After a job is finished, there are two types of results: ARC and d3plot. Both files are attached to SimXpert. The d3plot result file is attached first. a. Under File, select Attach Results b. File path, select the desired path c. Open, select nug_43a.dytr.d3plot d. Attach Options, select Both e. Click Apply f. View the Lagrangian results

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786 MD Demonstration Problems CHAPTER 43

Attach the Analysis Results File (continued) The ARC result file is attached second. a. File path, select the desired path b. Open, select NUG_43A.DYTR_EULER_FV1_0.ARC c. Attach Options, select Both d. Click Apply e. View the Outer Euler results

a c b

d

e

CHAPTER 43 787 Blastwave Hitting a Bunker

Attach the Analysis Results File (continued) a. File path, select the desired path b. Open, select NUG_43A.DYTR_EULER_FV2_0.ARC c. Attach Options, select Both d. Click OK e. View the Inner Euler results

a c

b d

e

788 MD Demonstration Problems CHAPTER 43

Display the Deformation Results Create a deformation plot of Lagrangian results. a. In the Model Browser tree, select all the Euler elements b. Select Hide c. Check to see that all Euler elements are hidden d. Results tab: Deformation e. Result entities: Result cases: nug_43a.dytr.d3plot, select Time 0.0100956 f. Results entities: Result type, select Displacement Components g. Click Target entities h. In current window, change Target entities to Elements i. In Main Window, select all Lagangian elements j. Plot Data, click Deformation

c

a

b

d

g f

e i j h

CHAPTER 43 789 Blastwave Hitting a Bunker

Display the Deformation Results (continued) a. Deformed display scaling: click True b. Click Update c. In Main Window, check the deformation plot

a

c

b

790 MD Demonstration Problems CHAPTER 43

Display the Stress Results Create a stress fringe plot of Lagrangian results. a. Deformed display scaling: click True b. Plot type, select Fringe c. Result entities: Result cases: nug_43a.dytr.d3plot, select Time 0.0100956 d. Results entities: Result type, select Stress Components e. Result entities: Deviation, select von Mises

a

e d c b

CHAPTER 43 791 Blastwave Hitting a Bunker

Display the Stress Results (continued) a. In current window, change Target entities to Elements b. n Main Window, select all Lagangian elements c. Click Fringe tab d. In current window, change Element edge display entities to Element edges e. Click Update f. In Main Window, check the stress fringe plot

a b

c d

f

e

792 MD Demonstration Problems CHAPTER 43

Display the Euler Pressure Iso-surface Results Create a pressure iso-surface plot of Eulerian results. a. In the Model Browser tree, select only the outer Euler elements (FV1) b.Select Show Only c. Check to see that all outer Euler elements are shown d. Plot type, select IsoSurface e. Result entities: Result cases: NUG_43A.DYTR.EULER_FV1_0.ARC, select Time 0.0101689 f. Results entities: Result type, select PRESSURE g. Click Target entities

c

a

b

g f d

e

CHAPTER 43 793 Blastwave Hitting a Bunker

Display the Euler Pressure Iso-surface Results (continued) a. In current window, change Target entities to Elements b. n Main Window, select all outer Eulerian elements c. Click IsoSurface tab d.:First value, enter 19.5244 e. Click Update f. In Main Window, check the iso-surface plot of the outer Euler zone

c a b

e

d

f

794 MD Demonstration Problems CHAPTER 43

Display the Euler Pressure Iso-surface Results (continued) a. In the Model Browser tree, select only the inner Euler elements (FV2) b.Select Show Only c. Check to see that all inner Euler elements are shown d. Name, select Create Attribute e. For Enter the plot attribute name, enter IsoSurf 02; click OK f. Result entities: Result cases: NUG_43A.DYTR.EULER_FV2_0.ARC, select Time 0.0101689 g. Results entities: Result type, select PRESSURE h. Click Target entities

c

a b

e d

h g

f

CHAPTER 43 795 Blastwave Hitting a Bunker

Display the Euler Pressure Iso-surface Results (continued) a. In current window, change Target entities to Elements b. n Main Window, select all inner Eulerian elements c. Click IsoSurface tab d. First value, enter 19.5244 e. Click Update f. In Main Window, check the iso-surface plot of the inner Euler zone

c

b a

e

d

f

796 MD Demonstration Problems CHAPTER 43

Display the Euler Pressure Iso-surface Results (continued) a. In the Model Browser tree, select elements b. Select Hide All c. In Main Window, check the iso-surface plot of the Eulerian elements and the stress/deformation plot of the Lagrangian elements

a

b c

CHAPTER 43 797 Blastwave Hitting a Bunker

Input File(s) File

Description

nug_43a.dat

MD Nastran input file for l=blast on bunker using Fast Coupling technique

nug_43b.dat

Geometry of Euler elements

nug_43c.dat

Geometry of Lagrangian structure elements