flow through bypass
flow through bypass
(OP)
LS,
Another piping problem I have is as follows:
We do have a large pipe (DN200) in which a scoop (DN100)is placed in the middle of the flow, that reduces conically to DN50. This pipe goes out of the pipe and is by-passed for about 0,8 m. In the by-pass a measuring section is placed (and thus creating additional resistance), and then it is connected to the main pipe again under a 90° angle (see sketch).
How can I setp up a calculation which part of the flow is going through the bypass section, depending on flow and viscosity in the main pipe.
Thanks in advance.
DYV
Another piping problem I have is as follows:
We do have a large pipe (DN200) in which a scoop (DN100)is placed in the middle of the flow, that reduces conically to DN50. This pipe goes out of the pipe and is by-passed for about 0,8 m. In the by-pass a measuring section is placed (and thus creating additional resistance), and then it is connected to the main pipe again under a 90° angle (see sketch).
How can I setp up a calculation which part of the flow is going through the bypass section, depending on flow and viscosity in the main pipe.
Thanks in advance.
DYV





RE: flow through bypass
I'm pretty sure you can safely disregard the friction drop in the main pipe over 80 cm, but the protruding pipe would constitute a "bluff body" in the flow that will shed von Karmen Streets and will play havoc with pressure at the point that the flow re-enters the main pipe. These perturbations can be pretty long lived and will certainly prevent the flow from being fully developed at the entry point.
I don't even know how I would set this up in a CFD program. Good luck with it.
David
RE: flow through bypass
Let your acquaintances be many, but your advisors one in a thousand' ... Book of Ecclesiasticus
RE: flow through bypass
Good luck,
Latexman
RE: flow through bypass
RE: flow through bypass
It is an excisting real situation. Through the piping flows oil of which flow and viscosity can vary, and the bypass with the scoop in the center is used to have a continuous sample from the main flow. In the by-pass there is a measuring section which could not be placed in the main flow. In the moment there is discussion about the refreshing rate through the by-pass, and whether there will be sufficient flow through the by-pass. This is why I would like to do some calculations to verify.
DYV
RE: flow through bypass
Good luck,
Latexman
RE: flow through bypass
Flow would not be possible as it is a by-pass. Flow is what I would like to estimate.
RE: flow through bypass
David
RE: flow through bypass
Let your acquaintances be many, but your advisors one in a thousand' ... Book of Ecclesiasticus
RE: flow through bypass
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: flow through bypass
I've seen this arrangement before. I'm sure the math is worked out already and this arrangement is intended to capture a specific percentage of flow. Research "sampling systems" or maybe "diversion systems". I don't think I have any of that old stuff where I can find it. Check in the field of Instrumentation Engineering or with instrumentation suppliers.
RE: flow through bypass
Let your acquaintances be many, but your advisors one in a thousand' ... Book of Ecclesiasticus