A company claims to be able to manufacture a vortex tube using air that reaches -250.°F cold side and +250.°F hot side (both at atmospheric pressure) with an inlet pressure of 20.0 psig and a hot side mass flow fraction of 50.0%.
Does their vortex tube violate the second law of thermodynamics? Assume constant specific heat ideal gas behavior and neglect any changes in kinetic and potential energy.