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Difference between surface average and surface integral

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Hi all

What is the difference between surface average and surface integral ?. Are they same or different?

Thank you

2 Replies Last Post 27.09.2016, 01:44 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 8 years ago 25.09.2016, 04:46 GMT-4
Hi

the surface integral is

"integrate over selected surface" ( my_function dx*dy )

while average integration is:

"integrate over selected surface" ( my_function*dx*dy ) / "integrate over selected surface" ( 1*dx*dy )

the only caveat I know, is when you limit the area via Boolean expression for the average, then you must retype it fully, as COMSOL ALWAYS divides by the TOTAL selected surface.

line and domain averages are similar

--
Good luck
Ivar
Hi the surface integral is "integrate over selected surface" ( my_function dx*dy ) while average integration is: "integrate over selected surface" ( my_function*dx*dy ) / "integrate over selected surface" ( 1*dx*dy ) the only caveat I know, is when you limit the area via Boolean expression for the average, then you must retype it fully, as COMSOL ALWAYS divides by the TOTAL selected surface. line and domain averages are similar -- Good luck Ivar

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Posted: 8 years ago 27.09.2016, 01:44 GMT-4
Thank you very much
Thank you very much

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