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Simulated and actual schlieren images show good agreement at earlier times, but the solid material is too stiff and not sufficiently plastic. The flap springs back after about 300 micro-seconds, which is not in qualitative agreement with the experiment. A detailed comparison of computational and experimental schlieren images can be found on a separate page.

- An animation of the simulated schlieren images showing also the shadow of the opening flaps is available: Simulated schlieren images at x=0.0m with flap deformation
- Further animations visualizing particular the fluid flow are available:
- Animations of dynamic fluid mesh adaptation
- Animation of distribution of computational domain to processors in fluid

z=0.444m (overall distance 1.964m) | z=0.896m, (overall distance 2.416m) |

The oscillations in the reflection process are no computational error, but occur because the detonation turned fully three-dimensional in the simulation. (Compare Schlieren plot of density on refinement levels, x=0)

Simulation details:

- Fluid
- gamma=1.24, p0=100 kPa
- Van Leer flux vector splitting with 2nd order MUSCL reconstruction, dimensional splitting
- CJ volume burn model
- Computational domain: [-0.39m,0.39m]x[-0.0375m,0.5625m]x[-0.9200m,0.8960m]
- AMR base level: 104x80x242, 3 additional levels, refinement factor 2,2,4
- Equivalent unigrid run 7,929,856,000 cells
- Approx. 40,000,000 cells used in fluid on average
- Tube and detonation fully refined
- No refinement for z<0 (to approximate Taylor wave)
- No maximal refinement for x<-0.1575m, x>0.1575m, y>0.15m

- Thickening of 2d mesh: 0.81mm on both sides (real thickness on both sides 0.445mm)
- 16 nodes 2.2 GHz AMD Opteron quad processor, PCI-X 4x Infiniband network

- Solid
- Aluminium, J2 plasticity model
- Specimen from z=0 to z=0.896m, middle axis along z-axis
- Middle of slot at x=0.0m, y=0.020195m, z=0.444m
- Mesh: 8577 nodes, 17056 elements
- Close-up of slot in solid mesh
- 2 nodes 2.2 GHz AMD Opteron quad processor, PCI-X 4x Infiniband network
- The flaps are allowed to hinge back freely. No nodes on mesh constrained. This causes convergence problems because of mesh distortions at approx. t=460micro-seconds.

- Ca. 4320h CPU to t=450 micro-seconds
- Source code: [fluid codes] [solid codes]

-- RalfDeiterding - 13 Feb 2006

I | Attachment | Size | Date | Who | Comment |
---|---|---|---|---|---|

FlapsDenCutX.mpg | 1250.1 K | 14 Feb 2006 - 01:50 | RalfDeiterding | Color plot of density, displacement in y-direction | |

FlapsDensity.mpg | 1547.3 K | 14 Feb 2006 - 01:50 | RalfDeiterding | Color plot of density at x=0, z=0.444m | |

FlapsLevSl.mpg | 1755.0 K | 14 Feb 2006 - 01:51 | RalfDeiterding | Schlieren plot of density on refinement levels at x=0, z=0.444m, part of deforming solid mesh | |

FlapsLevCutX.mpg | 967.4 K | 14 Feb 2006 - 01:52 | RalfDeiterding | Schlieren plot of density on refinement levels, x=0 | |

FlapsLevCutZ.mpg | 770.9 K | 14 Feb 2006 - 01:53 | RalfDeiterding | Schlieren plot of density on refinement levels, z=0.444m | |

FlapsSchlCutX.mpg | 658.5 K | 14 Feb 2006 - 01:55 | RalfDeiterding | Schlieren plot of density at x=0, corresponds to experimental schlieren images | |

FlapsDist.mpg | 1906.4 K | 14 Feb 2006 - 04:55 | RalfDeiterding | Distribution to processors in fluid |

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