I would like to know how to calculate the delta T for gaseous nitrogen when I depressurize it thru a regulator, let say the cylinder is at 2500psi and the output of the regulator is 125 psi.
From published information the J-T (isoenthalpic throttling) coefficient for nitrogen at 25 [sup]o[/sup]C, for 8.5 ata : 0.2155, and assuming a J-T coeff. linear relation with pressure, expressed as 0.2155 - 7.4 x 10[sup]-4[/sup] P, we can estimate the cooling effect after expansion by integrating between 8.5 and 170 ata of:
(0.2155 - 7.4 x 10[sup]-4[/sup] P) dP =
0.2155 (8.5-170) - 7.4 x 10[sup]-4[/sup] (8.5[sup]2[/sup] - 170[sup]2[/sup])/2 = -34.8 + 10.7 =
-24.1[sup]o[/sup]C.