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Name: Grant L.
Status: Other
Age: 30s
Location: N/A
Country: N/A
Date: N/A

Pure Nitrogen gas is used for energy storage in hydraulic accmulators. Some large, low pressure accmumlators have no membrane to separate the oil and nitrogen. The nitrogen eventually gets disolved/diffused into the oil and periodically needs to be recharged.

Does the nitrogen dissolve faster at higher pressures?
How deep into the oil will the nitrogen penetrate?

The general rule is: Gases become more soluble in a solvent when the pressure increases. This is expressed quantitatively by Henry's law that states that the pressure is proportional to the concentration of the dissolved gas -- P = k*C, where P is the gas pressure, k is an empirical constant, and C is the concentration of the dissolved gas (all quantities being in a consistent set of units. The "bends" suffered by deep sea divers is a consequence of the same trend in the solubility of nitrogen in blood.

As an aside, the solubility of gases to my knowledge, decreases with increasing temperature.

Vince Calder

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