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how to define the backflow total temperature

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Old   September 11, 2001, 08:53
Default how to define the backflow total temperature
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hanjun
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hi fluent user: i want to know how to define the backflow total temperature in modeling a furnace,the help file is " sets the total temperature of the inflow stream should the flow reverse direction",i don't know the meaning. thanks

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Old   September 13, 2001, 22:33
Default Re: how to define the backflow total temperature
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Erwin
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You should input an estimate of the outlet temperature. Should reversed flow occur at the outlet boundary, the program is able to give that flow a more appropriate temperature value based on your input. If no reversed flow occurs this input has no effect.
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Old   September 16, 2001, 09:20
Default Re: how to define the backflow total temperature
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hanjun
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thanks you for you anwser.if only there is whirlpool in the flow,the input haven't effect?
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Old   September 17, 2001, 13:17
Default Re: how to define the backflow total temperature
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Erwin
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No, the input only has effect when there is flow recirculating back into the domain again. The best way to avoid this is to move your exit boundary away from areas with vortices, for example the flow recirculation after a bend. If you can't do that, then you have to specify the backflow parameters as accurately as possible.
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Old   July 17, 2014, 04:00
Default reversed flow
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thermal energy is on a distinguished road
hi all,

ı have an rectangular geometry (lenght:76, width:27 mm). heat flux is applied from one of the vertical walls. ı have velocity inlet BC at lower part and also pressure outlet BC at upper part. velocity magnitute is zero (0) (no forced convection), initial gauge pressure is also zero and temperature is 298 K at velocity inlet BC. also, for pressure outlet BC gauge pressure is 0 and backflow temperature is set 298 K. initial temperature is also 298K.

the problem is that reversed flow occured.
"reversed flow in 34 faces on pressure-outlet 17"

the solution is converged but ı am not sure it is right or not.

any suggestion. thanks for you time.
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