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what does normal total heat flux symbol shows?
Posted 10 mar 2012, 23:54 GMT-5 Version 3.5a 1 Reply
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hi,
Please some body tell me what does the symbol positive or negative shows with the numeric value of normal total heat flux.Somtime it is negative and sometime it is positive.I am bit confused whether positive mean heat is going out from the boundry and negative mean its coming inside to the boundry? Sometime even high temprature body shows negative symbol.
Please help me.
Regards
tassawar
Please some body tell me what does the symbol positive or negative shows with the numeric value of normal total heat flux.Somtime it is negative and sometime it is positive.I am bit confused whether positive mean heat is going out from the boundry and negative mean its coming inside to the boundry? Sometime even high temprature body shows negative symbol.
Please help me.
Regards
tassawar
1 Reply Last Post 12 mar 2012, 03:47 GMT-4
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Posted:
1 decade ago
Hi
that probably comes from the definition of "normal". The "normal" vector of any boundary points outwards from the domain surrounded by the boundaries. This is "easy" to grab for external boundaries and in assembly mode, but in Union mode for internal boundaries these "continuity" boundaries are made unique and shared, hence there is no obvious up/down direction.
My way around is to take a close look to a boundary normal plot (check the plot "more" extension in V4
or plot the boundary normal vectors (nx,ny,nz) in 3.5
--
Good luck
Ivar
that probably comes from the definition of "normal". The "normal" vector of any boundary points outwards from the domain surrounded by the boundaries. This is "easy" to grab for external boundaries and in assembly mode, but in Union mode for internal boundaries these "continuity" boundaries are made unique and shared, hence there is no obvious up/down direction.
My way around is to take a close look to a boundary normal plot (check the plot "more" extension in V4
or plot the boundary normal vectors (nx,ny,nz) in 3.5
--
Good luck
Ivar