Conveners
C1OrF - Gas Mixture Properties and Behavior
- Peter Bradley (NIST)
- Sangkwon Jeong (KAIST)
NASA is designing an unmanned submarine to explore the depths of the hydrocarbon-rich seas on Saturn’s moon Titan. Data from Cassini Huygens indicates that the Titan polar environment sustains stable seas of variable concentrations of ethane, methane, and nitrogen, with a surface temperature around 93 K. The submarine must operate autonomously, study atmosphere/sea exchange, interact with the...
Application of partial pressure technology to combinations of one gas above its critical temperature (helium) mixed with a two-phase liquid (nitrogen) can result in liquid temperatures down to and below the nitrogen triple point. The thermodynamics of this process is developed and an experimental apparatus is described which was used to produce a helium/nitrogen bath temperature of 59.17 K, 4...
In this study, we use the Langmuir probe plasma diagnostics technique to investigate the dielectric properties of gas mixtures for cryogenic applications. In our previous studies we reported substantial enhancement in the dielectric strength of gaseous helium by adding small mole fractions of gaseous hydrogen. We performed the Boltzmann analysis to predict the dielectric strengths of several...
This study investigates the dielectric strength of cryogenic gas mixtures containing helium, hydrogen, and nitrogen under the operating conditions of a continuous cryogenic cooling loop for shipboard power systems. Substantial enhancement in the dielectric strength of gaseous helium, a relatively weak dielectric medium compared to liquid nitrogen, the standard cooling medium for high...
Prototypes of gaseous helium cooled High Temperature Superconducting (HTS) power cables and other high power density devices have been demonstrated. Additional superconducting power applications cooled with closed loop helium circulation are being explored either to exploit the higher power density of HTS cables at low temperatures (< 77 K) or to utilize superconducting materials such as MgB2...
Many high temperature superconducting (HTS) power devices have been successfully demonstrated in the power grid. Most of the HTS devices are cooled using liquid nitrogen as the cryogen. Gaseous helium is being explored as a viable option for cooling HTS power devices where higher power density is required making the operation at temperatures less than 65 K is necessary. Helium gas is...
A transient model for a cryogenic carbon dioxide capture (CCC) pump is presented. The pump separates carbon dioxide by desublimation from nitrogen in the gas mixture exhaust from power plants. Compared with other CCC methods, desublimation is commonly considered to be competitive when the concentration of carbon dioxide is low. It is necessary to explore the fully detailed physical mechanisms...
