- #1
davidgrant23
- 22
- 0
Hi there,
I have a double-barreled question for you all. So I have two pipes connected to each other. The first pipe is 0.64cm and has a Re = 5000, the second pipe is 4.5cm and has a Re = 700. The two are connected so that the gas expands from the the first pipe to the second.
Now, I wish to measure the flow velocity in the 2nd, larger diameter pipe. The Re I provided for the 2nd pipe suggests it is laminar, but I cannot simply place the air velocity meter right at the expansion between the two pipes as I would think it would be turbulent (expansion causing turbulence) right at the connection. My question is, is there a way of calculating how long along the length of the 2nd pipe I should place the velocity probe to ensure that the flow is laminar and not turbulent (from the expansion)?
Also, if in the event that the flow has to be turbulent, is measuring the velocity with a hot wire anemometer in turbulent flow just a case of taking a time averaged value, to negate the effect of turbulent fluctuations?
Thanks,
Dave
I have a double-barreled question for you all. So I have two pipes connected to each other. The first pipe is 0.64cm and has a Re = 5000, the second pipe is 4.5cm and has a Re = 700. The two are connected so that the gas expands from the the first pipe to the second.
Now, I wish to measure the flow velocity in the 2nd, larger diameter pipe. The Re I provided for the 2nd pipe suggests it is laminar, but I cannot simply place the air velocity meter right at the expansion between the two pipes as I would think it would be turbulent (expansion causing turbulence) right at the connection. My question is, is there a way of calculating how long along the length of the 2nd pipe I should place the velocity probe to ensure that the flow is laminar and not turbulent (from the expansion)?
Also, if in the event that the flow has to be turbulent, is measuring the velocity with a hot wire anemometer in turbulent flow just a case of taking a time averaged value, to negate the effect of turbulent fluctuations?
Thanks,
Dave