# Max possible air flow through a tube

• siegoo
In summary, the conversation revolved around determining the maximum flow of air from a space with 1 atmosphere pressure on the left side to an infinite vacuum on the right side, through a restriction in the shape of a round tube. The purpose was to calculate the flow in one minute and discuss if changing the size of the restriction would have any impact. The calculation for this scenario is called an orifice plate flow and is dependent on pressure difference, density, and thermodynamic properties for compressible substances like air, as well as a constant factor determined by the shape of the opening (in this case, k=0.82 for a round hole longer than its diameter).

## Homework Statement

I had a discussion with some of my friends about this matter, but my physics basics related to fluid flow dynamics aren't well enough to draw a conclusion, so here it is:

On the left side of the diagram is a space with infinite amount of air (breathable Earth air) at pressure of 1 atmosphere, on the right side is infinite vacuum

Problem - determine maximum possible flow through the restriction (shape is a round tube for the ease) in a given time period - 1 minute and will decrease/increase of the size (D=10mm compared to D=1000mm) be of any significance

http://img17.imageshack.us/img17/7366/diagram1.gif [Broken]

the discussion wasn't about increasing the flow by adjusting the shape of the restriction or any other variables, just to determine how much of the air from the left side can travel to the right side in one minute

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You are looking for a calculation called an oriface plate flow.
It only depends on the pressure difference, density, and for a compressible substance (like air) some thermodynamic properties.
And a constant which depends on the shape of the opening, for a round hole that is much longer than it's diameter this is k=0.82

## 1. What factors affect the maximum air flow through a tube?

The maximum air flow through a tube is affected by several factors, including the diameter of the tube, the length of the tube, the material of the tube, and the pressure and temperature of the air being pushed through the tube. These factors can either increase or decrease the maximum air flow.

## 2. How do I calculate the maximum air flow through a tube?

The maximum air flow through a tube can be calculated using the Bernoulli's equation, which takes into account the diameter, length, and material of the tube, as well as the pressure and temperature of the air. Additionally, using a flow meter or conducting experiments can also help determine the maximum air flow through a tube.

## 3. Can the maximum air flow through a tube be increased?

Yes, the maximum air flow through a tube can be increased by changing certain factors. For example, increasing the diameter of the tube or decreasing its length can result in a higher maximum air flow. Additionally, using a smoother material for the tube can also increase the air flow.

## 4. Is the maximum air flow through a tube always constant?

No, the maximum air flow through a tube can vary depending on the conditions and factors mentioned earlier. For example, if the pressure or temperature of the air changes, the maximum air flow through the tube can also change. It is important to consider all factors when determining the maximum air flow through a tube.

## 5. What are some practical applications of knowing the maximum air flow through a tube?

Knowing the maximum air flow through a tube can be useful in various industries, such as HVAC systems, pneumatic systems, and fluid mechanics. It can also be helpful in designing and optimizing ventilation systems, determining the efficiency of air compressors, and calculating the flow rate of gases in chemical processes.