Energy content of air at pressure

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    Air Energy Pressure
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Discussion Overview

The discussion centers on calculating the energy content of air at a specified volume and pressure, particularly focusing on the case of 1 bar and 1 liter, and later extending to 3 bar and a flow rate of 0.265 liters per second. Participants explore the relationship between pressure, volume, and the energy available for work.

Discussion Character

  • Exploratory
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant inquires about calculating the energy content of air at a given volume and pressure, specifically asking for methods to determine the energy available for work.
  • Another participant suggests that energy can be calculated as pressure times volume, but notes that the method of harnessing this energy affects the actual usable energy.
  • There is a clarification that Watts is a unit of power, not energy, and a participant provides a formula involving pressure and volume in SI units.
  • A participant specifies that they are interested in the energy content of air contained at 3 bar pressure and a flow rate of 0.265 liters per second.
  • One participant calculates the energy using the provided values, converting bar to N/m² and liters to cubic meters, arriving at a result of 300 Nm.
  • Another participant confirms the calculation and further explores how to derive power from the energy calculated by multiplying by distance and dividing by time.

Areas of Agreement / Disagreement

Participants generally agree on the basic calculations involving pressure and volume, but there is no consensus on the broader implications of these calculations or the specific methods for harnessing the energy. The discussion remains exploratory with various interpretations of the calculations presented.

Contextual Notes

There are limitations regarding the assumptions made about the flow rate and the conditions under which the energy is calculated. The discussion does not resolve how to apply these calculations in practical scenarios or the efficiency of energy conversion methods.

Who May Find This Useful

This discussion may be useful for individuals interested in thermodynamics, energy calculations in fluid mechanics, or those exploring practical applications of pressure and volume in energy systems.

Gravity2014
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Hi can anyone point me in the direction, or tell me how you can calculate the energy content of air at a given volume and pressure? Let's say 1 bar and 1 litre. Also is there a calculation for working out the energy available in that figure to perform work? Thank you.
 
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At a basic level It's just pressure times volume. How much you can harness depends on the method.
 
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Ok, is it calculated in bar ? And it the answer in Watts?) Thanks, I am having trouble finding it anywhere.
 
Watts is power, not energy, but if you want SI, it is just N/m^2 * m^3 = N-m.

No offense though, but I'm sensing you might be in over your head on something here. If you give us some info on what you are trying to do, we might be able to be of more help.
 
No offence taken, I didn't mention it could be a flow rate of 1 litre per second at 1 bar, hence the possible power conversion. For now I am just trying to find the energy content if contained and not flowing.The actual question I'm trying to solve from this is 3 bar pressure, 0.265 Litres per second. Thank you.
 
So 3 bar =300,000 N/m^2 (1 bar = 100,000N/m^2) * 0.00026500 m^3 (1Litre = 0.0010000 m^2) = 300Nm ?)))
 
Thank you)) to take it one stage furthur , I just times by the distance the force is used over and divide by time for the power? So I get 300Nm x 0.20M /1s = 60 watts?)
 

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