Flow in a branch line

[mufasa1]

Gentlemen,

There is a 20" main pipe.
The fluid velocity in the pipe is 1 mt/sec.

Assume that we take a perpendicular 1" branch line from
the main pipe, and then tie it back to the main line a few meters ahead. The material will be the same.

Please see the attached link for simple scheme.

Will there be a flow in the branch line?

Awaiting your response.

Regards,

 

[europipe]

Barely, what is the purpose of the branch line?

Greetings

 

[katmar]

There has to be a flow because the pressure drops over the two paths have to be equal.

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Engineering & Risk Analysis Software

http://katmarsoftware.com

 

[gegio1960]

in case of liquid there could be no flow....

 

[SNORGY]

I think if there is a pressure difference from point 1 to point 2, then there will be non-zero flow in both paths between point 1 and point 2, unless the viscosity and surface tension and the like are such that the small line, for all intents and purposes, cannot pass flow at all.

Regards,

SNORGY.

 

[BigInch]

Its doubtful you will put a bypass line there without some other device or instrument, which may offer enough resistance to effectively limit the flow to near zero. Furthermore, you must capture some flow from the mainline streaming past, which requires a change of direction of that momentum. The typical treatment of parallel flows proportions flow from a joint simply by the ratio of areas, without regard for any changes required to the momentum vector. There is a certain amount of head loss associated with changing that vector, hence remaining head may not be sufficient to effect flow in the bypass. For example, a small pump is often placed in such parallel 1" lines to assure that flow actually reaches an instrument located in the bypass branch, such as a densitometer.

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[whammett]

Biginch is correct. There will be a pressure difference but you have to take into effect the momentum of the liquid. If its just 2 90degree bends to the branch, it will be a stagnant line. You would have to try and "induce" flow so to speak. Easiest way is to angle the two lines attatching to the main flow.
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[mufasa1]

Gentlemen,

Thank you for the feedback,

The 20" main line carries hot geothermal brine into an ORC Heat Exchanger. The tubings inside the Heat Exchanger are 1". Purpose of this 1" branch line is to simulate the scaling effect inside the tubings of the heat exchanger on a branch line tied to the main transmission line.

If there is a flow in this branch line then we might see the scaling effects.

Cheers,

 

[BigInch]

You'll probably just see some turbulence near the 90deg branch connections ... no flow.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
"Being GREEN isn't easy." Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.liv

 

[katmar]

Whatever the actual flow rate in the 1" branch, it is very likely that the velocity will be MUCH less than through the 1" heat exchanger tubes. The branch line wall temperature is also likely to be very different from your heat exchanger situation. If the flow velocity and wall temperature in the branch are not representative of the heat exchanger tubes then I don't think you will get much useful information about scaling from this exercise.

Katmar Software
Engineering & Risk Analysis Software

http://katmarsoftware.com