How to Calculate Air Flow Rate for a Cylindrical Vessel with Perimeter Holes?

AI Thread Summary
To calculate the air flow rate for a cylindrical vessel with perimeter holes, the discussion centers on a steel drum measuring 22.5 inches in diameter and 34.5 inches in height, featuring 50 holes of 13 mm each. The required air flow rate is sought under a vacuum of 1 inch of H2O at 70°F and 26% relative humidity. An estimated flow rate of 280 SCFM is suggested, assuming a discharge coefficient of 0.7 for the holes. The calculation utilizes Bernoulli's equation, treating the static pressure as velocity pressure. The accuracy of the calibration standard is questioned, indicating potential concerns with the measurement method.
naboulsi
Messages
1
Reaction score
0
We are having trouble calculating a required ft^3 per minute air flow for a particular vessel which was constructed to measure the accuracy of a vacuum machine.
Our vessel is a steel cylindrical drum 1mm thick with a diameter of 22.5" and a height of 34.5". It has 50 holes around the lower perimeter measuring 13 mm in diameter. What is the air flow rate if we pull a vacuum of 1" of H20 at a temp of 70 deg. F and Relative Humidity of 26%. Can anyone help us out?
 
Engineering news on Phys.org
Hi naboulsi,
This probably belongs in the mechanical engineering forum. Anyway, assuming your system is maintaining 1" water vacuum, steady state, and assuming a discharge coefficient for your drilled holes of roughly 0.7 (from experience) I'd estimate your flow rate to be 280 SCFM.
 
The way to calculate it is to use Bernoulli's equation: assuming perfect nozzles, that 1" of static pressure becomes your velocity pressure.
 
That is a pretty poor sounding calibration standard.
 

Thread 'Race car suspension Class'

Posted June 2024 - 15 years after starting this class. I have learned a whole lot. To get to the short course on making your stock car, late model, hobby stock E-mod handle, look at the index below. Read all posts on Roll Center, Jacking effect and Why does car drive straight to the wall when I gas it? Also read You really have two race cars. This will cover 90% of problems you have. Simply put, the car pushes going in and is loose coming out. You do not have enuff downforce on the right...
View full post »

Thread 'Cantilever help'

I'm trying to decide what size and type of galvanized steel I need for 2 cantilever extensions. The cantilever is 5 ft. The space between the two cantilever arms is a 17 ft Gap the center 7 ft of the 17 ft Gap we'll need to Bear approximately 17,000 lb spread evenly from the front of the cantilever to the back of the cantilever over 5 ft. I will put support beams across these cantilever arms to support the load evenly
View full post »
Thread 'What's the most likely cause for this carbon seal crack?'

Thread 'What's the most likely cause for this carbon seal crack?'

We have a molded carbon graphite seal that is used in an inline axial piston, variable displacement hydraulic pump. One of our customers reported that, when using the “A” parts in the past, they only needed to replace them due to normal wear. However, after switching to our parts, the replacement cycle seems to be much shorter due to “broken” or “cracked” failures. This issue was identified after hydraulic fluid leakage was observed. According to their records, the same problem has occurred...
View full post »

Similar threads

How to determine air velocity in open ended tube?
Replies
9
Views
2K
How Do You Calculate Pressure and Flow for an Air Float Conveyor?
Replies
3
Views
1K
Volumetric flow from vessel through pipe to another vessel
Replies
8
Views
3K
Flow rate of air in discharging reservoir
Replies
1
Views
2K
How to calculate effective pump flow-rate across a filter?
Replies
2
Views
4K
How long will it take for compressed air to reach 29 psi?
Replies
5
Views
2K
Determine air flow rate from pressure drop and hose diameter
Replies
3
Views
8K
How can I calculate the flow rate created by a fan connected to an engine?
Replies
1
Views
2K
Help with measure air flow rate with pressure difference in a cylinder
Replies
3
Views
3K
How to calculate pressure and flow rate of an air jet?
Replies
10
Views
12K

Hot Threads

Recent Insights

Back
Top