Buoyancy effects on liquid nitrogen film boiling in vertical flow
Buoyancy effects on liquid nitrogen film boiling in vertical flow
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Buoyancy effects on liquid nitrogen film boiling in vertical flow
Film boiling transition temperature for cryogenic tissue cooling by liquid nitrogen
Gravity and size effects on film boiling from horizontal cylinders, recommending formulas for wavelength and minimum heat flux predictions
Pressure, subcooling and diameter effects on liquid nitrogen film boiling on thin horizontal wires, using high speed movies
Buoyancy effects on liquid nitrogen film boiling in vertical flow, using resistance heated test apparatus
Film boiling liquid hydrogen vertical flowing system, determining buoyancy effects on hydrodynamic and heat transfer characteristics
The dispersion relation is evaluated numerically for Taylor waves in a viscous unstable interface with surface tension. The solution takes account of transverse curvature and the numerical evaluations apply to horizontal cylindrical, as well as to plane, interfaces. The result is verified with frequency and wavelength data obtained during film boiling on horizontal wires. A very general empirical correlation is given, en passant, for the vapor blanket thickness during film boiling.
Tests of cryogenic chilldown in a vertical stainless steel tube are simulated using computational fluid dynamics (CFD). Subcooled liquid nitrogen enters the room-temperature tube at one end, resulting in film boiling and eventual quenching of the tube walls. A CFD-based modeling framework employing the mixture multiphase model has been developed to simulate this chilldown process and applied to validate it against experimental data. Extensive sensitivity studies have been performed to create a consistent modeling framework, and a two test conditions are simulated to test the modeling capability. The importance of the rewetting temperature and its relation to the foam limit temperature is discussed and is considered in the CFD model. The presented results demonstrate a qualitatively consistent representation of the film boiling and quenching regime. However, the quantitative accuracy of the simulations varies with the test conditions. Simulated vapor volume fraction distributions are also presented, although the current lack of experimental volume fraction data does not permit a comparison.
Tests of cryogenic chilldown in a vertical stainless-steel tube are simulated using computational fluid dynamics (CFD). Subcooled liquid nitrogen enters a room-temperature tube at one end, resulting in film boiling and eventual quenching of the tube walls. A CFDbased modeling framework employing the mixture multiphase model was developed to simulate this chilldown process and was applied to validate it against experimental data. Extensive sensitivity studies have been performed to create a consistent modeling framework, and a range of test conditions are simulated to assess the modeling capability. The importance of the rewetting temperature and its relation to the foam limit temperature is discussed and considered in the CFD framework. The presented results demonstrate a qualitatively consistent representation of the film boiling and quenching regime. However, the quantitative accuracy of the simulations varies with the test conditions. In addition, simulated distributions of the vapor volume fraction are presented, but the current lack of experimental volume fraction data prevents comparisons.
Tests of cryogenic chilldown in a vertical stainless-steel tube are simulated using computational fluid dynamics (CFD). Subcooled liquid nitrogen enters a room-temperature tube at one end, resulting in film boiling and eventual quenching of the tube walls. A CFDbased modeling framework employing the mixture multiphase model was developed to simulate this chilldown process and was applied to validate it against experimental data. Extensive sensitivity studies have been performed to create a consistent modeling framework, and a range of test conditions are simulated to assess the modeling capability. The importance of the rewetting temperature and its relation to the foam limit temperature is discussed and considered in the CFD framework. The presented results demonstrate a qualitatively consistent representation of the film boiling and quenching regime. However, the quantitative accuracy of the simulations varies with the test conditions. In addition, simulated distributions of the vapor volume fraction are presented, but the current lack of experimental volume fraction data prevents comparisons.
Minimum film boiling heat flux in vertical flow of liquid nitrogen
Liquid-liquid or solid-liquid interface Leidenfrost film boiling, deriving heat transfer coefficient for liquid drop floating on cryogenic fluid
Liquid He II, determining correlation of depth effect on film boiling heat transfer with vapor film geometry from motion pictures
Heat transfer analysis for cellular model of pool film boiling - optimal boundary value process
Hydrodynamic model for liquid or solid on liquid in Leidenfrost film boiling
Relative velocity effect on vaporization times and heat-transfer coefficients of water drops in Leidenfrost film boiling on heated rotating wheel
Liquid nitrogen saturated film boiling from wire at pressures up to critical, discussing liquid- vapor interface configuration
Forced flow heat transfer coefficients for laminar film boiling interface on vertical surface