How to convert air flow into pressure?

AI Thread Summary
Converting high airflow from an air pump into high pressure is challenging, as centrifugal pumps are designed for low pressure and high flow. Attempts to increase pressure using a cone at the output were ineffective, as it merely reduced airflow without raising pressure. A valve can be utilized to regulate flow, which may help increase pressure, but the pump's design limits its capability. Centrifugal compressors can achieve high pressure, but the specific pump in question is more akin to a blower or fan. Understanding the performance curve of these devices is crucial, as they inherently trade off flow for pressure within their design limitations.
Artlav
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Let's say i have an air pump which produce plenty of air flow, but almost no pressure.
Is there a simple way to turn this high flow, low pressure into high pressure, low flow?

I'm thinking something akin to a gearbox turning fast spin, low torque of a motor into a high torque, slow spin output.
Or basically something like a lever - a simple mechanical concentration of force.

I tried putting a cone at the output, but it just reduces the amount of air going out without increasing the pressure.
 
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Wind turbine -> electricity -> compressor -> any pressure you like.
 
Artlav said:
Let's say i have an air pump which produce plenty of air flow, but almost no pressure.
Is there a simple way to turn this high flow, low pressure into high pressure, low flow?
You describe it as a "pump", which implies that it is a high pressure, low flow device, but then say it is generating high flow and almost no pressure. That doesn't make a lot of sense, but if the flow is higher than you need, you can probably just put a valve on the system to reduce the flow, which will increase the pressure.

But it would help a lot if you provided more details about the pump and the system it is connected to.
I tried putting a cone at the output, but it just reduces the amount of air going out without increasing the pressure.
When you say "output", do you mean output to the air? The output to the air always has to be equal to atmospheric pressure because there is nothing to constrain it.
 
It's a centrifugal "pump" like the image below, used to fill up air mattresses.

It produces a lot of air flow, but almost no pressure.
That is, it can quickly inflate a garbage bag, but won't force any air into a regular party balloon.
The latter is what i was thinking of using it for.

61kzBSjkvFL._SY355_.jpg
 
You can buy electric balloon pumps. They do two balloons at once. Under $40. Perhaps cheaper, I didn't look hard.
 
CWatters said:
You can buy electric balloon pumps.
I know.
But that is not what the question is about.
 
Sorry, but there isn't much that can be done to increase the pressure: it is purposely designed for low pressure so it doesn't pop air mattresses.
 
That is a centrifugal compressor if I'm not wrong. They CANNOT produce high pressure, especially with a gaseous medium.
 
Centrifugal compressors can produce high pressure, but this one isn't designed to. It's more of a blower/fan than a compressor (though the difference is largely colloquia).

Fans, blowers, pumps, compressors, whatever all have a characteristic performance curve whereby higher flow occurs at lower pressure and vice versa (shape is roughly like the upper right quarter of a circle). But there is a maximum pressure that they can achieve at zero flow. The performance curve for this one was purposely selected to provide a maximum pressure that won't pop an air mattress.
 
  • #10
russ_watters said:
Centrifugal compressors can produce high pressure, but this one isn't designed to. It's more of a blower/fan than a compressor (though the difference is largely colloquia).

Fans, blowers, pumps, compressors, whatever all have a characteristic performance curve whereby higher flow occurs at lower pressure and vice versa (shape is roughly like the upper right quarter of a circle). But there is a maximum pressure that they can achieve at zero flow. The performance curve for this one was purposely selected to provide a maximum pressure that won't pop an air mattress.

Well I did not know that. Russ could you give me some examples of high pressure centrifugal compressors. I will appreciate it. Thanx
 
  • #11
Rippetherocker said:
Well I did not know that. Russ could you give me some examples of high pressure centrifugal compressors. I will appreciate it. Thanx

A lot of turboshaft and turboprop jet engines use centrifugal compressors, which will typically give a pressure ratio of something like 5:1 per stage (so a 2 stage centrifugal compressor can give ~25:1, though this depends on the specifics of each design). Wiki actually has a pretty good article on this: http://en.wikipedia.org/wiki/Centrifugal_compressorhttp://en.wikipedia.org/wiki/Centrifugal_compressor EDIT: actually, come to think of it, a high(ish) pressure centrifugal compressor you might be more familiar with also exists in many modern cars - specifically, a turbocharger. They all run centrifugal compressors as well.
 
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