Case 2: Loop in the thinfilm code

Benchmarks to check PBC in thin film code

ILL RYU

May 31, 2010

From these benchmarks, we like to confirm if the periodic boundary condition works properly. To do that, two models are prepared as following figures. In the first model, dislocaiton loop is placed at the center of the simulation domain. In the other model, dislocaiton loop is split and is put into both right and the left surface.

Model geometries

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  [Dislocaiton loop at the center]

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  [Splited Dislocaiton loop at the right and left surfaces]

To check if PBC works, forces at the nodes are printed out in each cases. If forces output in both cases are the same, we can conclude PBC works well in the thinfilm code.

Test cases

In the thinfilm code, there are several flags which can turn on'off the spectral method (DEFS += -D_TFIMGSTRESS), with or without virtual segments (DEFS += -D_NOVIRTUALSEG) and with or without the Yoffe image stress (DEFS += -D_NOYOFFESTRESS). In order to test these different cases, force outputs are compared as the following table.

Test cases	Spectral method	Virtural segment	Yoffe stress
1.Loop_force_NoImg_NoVS_NoYoffe	OFF	OFF	OFF
2.Loop_force_NoImg_NoVS_YesYoffe	OFF	OFF	ON
3.Loop_force_NoImg_YesVS_NoYoffe	OFF	ON	OFF
4.Loop_force_NoImg_YesVS_YesYoffe	OFF	ON	ON
5.Loop_force_YesImg_NoVS_NoYoffe	ON	OFF	OFF
6.Loop_force_YesImg_YesVS_YesYoffe	ON	ON	ON

RESULTS

Force output

case 1:Loop_force_NoImg_NoVS_NoYoffe

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case 2: Loop_force_NoImg_NoVS_YesYoffe

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case 3:Loop_force_NoImg_YesVS_NoYoffe

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case 4:Loop_force_NoImg_YesVS_YesYoffe

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case 5:Loop_force_YesImg_NoVS_NoYoffe

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case 6:Loop_force_YesImg_YesVS_YesYoffe

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Stress output

case 1:Loop_Tot_YesImg_NoVS_NoYoffe

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case 2: Loop_Tot_YesImg_NoVS_YesYoffe

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Conclusion

From the plot, we can conclude that PBC works well in thinfilm code, because the force and stress output fits well to each other. Moreover, we can see the traction boundary condition is safisfied on the surface of the thin film.

Input & plot files

Media: TBD
Media: TBD