Mixing gasses
Mixing gasses
(OP)
Dear all,
I've been asked to solve a problem involving fluid dynamics and I wonder if anyone could help me find a way to approach this problem.
Situation:
Two gasflows of different flow and temperature are mixed using a T-piece.
Known or previously calculated values:
flows, temperatures of both streams (multiple scenarios).
and density
Question:
How to calculate distance traveled for the mixed stream until gas temperature is homogenous?
I've been asked to solve a problem involving fluid dynamics and I wonder if anyone could help me find a way to approach this problem.
Situation:
Two gasflows of different flow and temperature are mixed using a T-piece.
Known or previously calculated values:
flows, temperatures of both streams (multiple scenarios).
and density
Question:
How to calculate distance traveled for the mixed stream until gas temperature is homogenous?





RE: Mixing gasses
RE: Mixing gasses
I'm also afraid that this is one of those non lineair problems with a strong dependance of starting conditions.
In other words, withouth a static mixer theres no telling what will happen?
Greets and thanks,
RE: Mixing gasses
RE: Mixing gasses
I've seen ethylene climb over N2 during purges of pipelines, this was at low reynolds numbers or static conditions.
RE: Mixing gasses
pipe diameters all DN600 (600mm)
both streams are of same composition (smoke)
largest stream comes in the T-piece horizontally
(T= approx 200 degC).
other stream (massflow about 1/3rd) comes in from top (branch)
(T = approx 500 degC).
all speeds in excess of 15 m/s... so they are turbulent
combined stream enters a smokestack after about 10m.
The client is afraid for hotspots downstream of the T-piece so special steel grade is used. Question to me is what length of special pipe is needed downstream of the T-piee until connection to normal grade steel.
Intuitively you would say injecting the hot stream perpendicular at these speeds would create such turbulence that temperature difference is immediately nullified... but how can you say for shure... is there a way to play it safe (except for changing all the piping domwstream into special grade which is expensive)?
RE: Mixing gasses