NTWO—A Nitrogen-Properties Package

  • K. J. Pew
  • R. C. Hendricks
  • R. J. Simoneau
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 16)


Cryogenic nitrogen is inert, inexpensive, and generally available in large quanti­ties at many research centers. It is used for cooling equipment, heating or cooling other fluids, as a modeling fluid, and in many cases as the primary test fluid in a heat-transfer and fluid-dynamics research, ntwo is a Fortran iv family of subroutines which was developed on a 7094–7044 DCS machine to determine the thermodynamic and transport properties of nitrogen, and to be used in conjunction with other research programs. The ntwo property package is subdivided into subroutines and functions for computing the individual properties. The individual subroutines may be used independently of subroutine ntwo if the user’s requirements are of a more restricted nature (say, memory- or time-limited). A descriptive breakdown of all the functions and subroutines used by the master subroutine will be given elsewhere [1].


Sonic Velocity NASA Lewis Research Cool Equipment Cryogenic Engineer State Variable Pressure 
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Copyright information

© Springer Science+Business Media New York 1971

Authors and Affiliations

  • K. J. Pew
    • 1
  • R. C. Hendricks
    • 1
  • R. J. Simoneau
    • 1
  1. 1.NASA Lewis Research CenterClevelandUSA

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