Which standard provides information on material properties? I want to find the density of air at 7 MPa; the temperature isn’t exactly clear yet, so I’ll use 40 degrees for now
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Which standard provides information on material properties? I want to find the density of air at 7 MPa; the temperature isn’t exactly clear yet, so I’ll use 40 degrees for now
Is there a formula, or is it based on engineering experience?
Under a certain pressure, does temperature have a significant impact on air density?
pV = znRT; since z is too complex and lacks sufficient data to support its use, it can be considered as 1. Temperature t + 273 = temperature T; by substituting these values into the equation, we can determine the impact. The difference between normal room temperature air and 70*1.29 is not significant, so such an estimation is sufficient
Aspen simulation is generally used
I did some testing: when using the ideal gas law to calculate the density of nitrogen, the deviation in density was over 5% at 20 MPa, and it exceeded 38% at 70 MPa (at a temperature of 20°C). Therefore, it is still recommended to use lookup tables for such calculations. For property calculation software, refprop or coolprop can be chosen.