How do you calculate BTU of expanding compressed air

In summary, there is a measure of the cooling effect from the release of compressed air through a nozzle in BTU's, which is calculated by multiplying 1 PSI m3 by 6.535. This relates to the conversion between the unit of energy (BTU) and the unit of pressure (PSI).
  • #1
riderb
1
0
I would like to know if there is a measure, in BTU's, of the cooling effect from the release of compressed air through a nozzle and how it relates to PSI
 
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  • #2
riderb said:
I would like to know if there is a measure, in BTU's, of the cooling effect from the release of compressed air through a nozzle and how it relates to PSI

BTU is the unit of energy and PSI is the unit of pressure. 1 PSI = 6894.757 N/m2

I BTU = 1055 Nm

Now multiply the unit PSI by m3 i.e volume SI unit you get 1 PSI m3 = 6894.757 Nm

1 BTU = 1055 Nm

So 6894.757 Nm = 6.535 BTU
So 1 PSI m3 = 6.535 BTU
 

Related to How do you calculate BTU of expanding compressed air

1. How do you calculate the BTU of expanding compressed air?

The BTU (British Thermal Unit) of expanding compressed air can be calculated by using the following formula: BTU = V x (P2 - P1) x 0.000293, where V is the volume of the compressed air in cubic feet, P2 is the final pressure in psi (pounds per square inch), and P1 is the initial pressure in psi.

2. What are the units used to express BTU of expanding compressed air?

The unit used to express BTU of expanding compressed air is BTU per cubic foot (BTU/ft3).

3. Can the temperature of the compressed air affect the BTU calculation?

Yes, the temperature of the compressed air can affect the BTU calculation. The formula for calculating BTU assumes that the temperature of the compressed air remains constant. If the temperature changes during expansion, the calculation may not be accurate. In this case, it is best to measure the temperature before and after the expansion and adjust the calculation accordingly.

4. Is there a difference between calculating BTU for expanding compressed air and other substances?

Yes, there is a difference in the formula used to calculate BTU for expanding compressed air compared to other substances. This is because compressed air is considered an ideal gas, meaning that it follows the ideal gas law, while other substances may not. Therefore, the formula for calculating BTU for compressed air takes into account the properties of an ideal gas.

5. Can the BTU calculation be used to determine the work done during expansion?

No, the BTU calculation only measures the heat energy released or absorbed during expansion. To determine the work done during expansion, a separate calculation using the ideal gas law and the change in volume and pressure must be performed.

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