The simplified exchange approximation (SEA) method for calculation of infrared radiative transfer, used for general circulation model (GCM) climate simulations at the Geophysical Fluid Dynamics Laboratory (GFDL) and other institutions, has been updated to permit inclusion of the effects of methane (CH4), nitrous oxide (N2O), halocarbons, and water-vapor–air molecular broadening (foreign broaden...

A completely revised version of the REFPROP refrigerant properties database is described. This program is based on the most accurate pure fluid and mixture models currently available. It implements three models for the thermodynamic properties of pure fluids: the modified Benedict-Webb-Rubin (MBWR) and Helmholtz equations of state, and an extended corresponding states (ECS) model. Mixture calcu...

This paper is concerned with the notion of path dependence as a framework to understand technological trajectories. The notion of path dependence has been deployed in the economic history and historical sociology literatures to explain sequences of events related mainly to technological and institutional evolution. We adopt a notion of path-dependence that subdivides sequences of events into se...

Mechanically refrigerated test chambers are classified as either single stage low (-40 °C) or cascade ultralow (-70 °C) temperature systems. While cascade systems are reliable and versatile, the potential for leakage between stages within a cascade heat exchanger remains. Further, the need for two compressors and increased control mechanisms can make the system more and more complex. The only m...