Highly subcooled liquid

Highly subcooled liquid It is a liquid that does not flash after passing through the PRV. 

Type 2 Highly subcooled liquid and noncondensable gas, condensable vapor, or both enter the PRV and the liquid does not flash. 

Carey van P (1992) Liquid-vapor phase-change phenomena. An introduction to the thermophysics of vaporization and condensation processes in heat transfer equipment. Hemisphere, New York Celata GP, Cumo M, Mariani A (1997) Experimental evaluation of the onset of subcooled flow boiling at high liquid velocity and subcoohng. Int J Heat Mass Transfer 40 2979-2885 Celata GP, Cumo M, Mariani A (1993) Burnout in highly subcooled water flow boiling in small diameter tubes. Int J Heat Mass Transfer 36 1269-1285 Chen JC (1966) Correlation for boiling heat transfer to saturated fluids in convective flow. Ind Eng Chem Process Des Develop 5 322-329... 

The combined effect of turbulent convection from liquid with high subcooling and radiation for film boiling on a flat surface was analyzed by Hamill and Baumeister (1967), resulting in the expression... 

A) The surface overheating at CHF in a highly subcooled flow is caused by poor heat transfer capability of the liquid core. 

A highly subcooled flow channel, even at CHF, is occupied almost entirely by a liquid core as shown in Figure 5.12. It can be postulated that the convective heat transfer of the liquid core is the limiting factor for occurrence of CHF at the wall. The following ways of analyzing the liquid core convective capability have been suggested ... 

Westendorf, W. H., and W. F. Brown, 1966, Stability of Intermixing of High-Velocity Vapor with Its Subcooled Liquid in Cocurrent Streams, NASA TN D-3553, Lewis Res. Ctr., Cleveland, OH. (6) Westinghouse Electric Corp., 1969, Thermal Conductivity of Crud, Rep. WAPD-TM-918, Pittsburgh, PA. (14)... 

Analytes may accumulate in the sorption phase either by adsorption onto the surface of solid sorbent materials or by absorption in absorbent liquids or polymers that behave like subcooled liquids.The advantage of solid adsorbents is the potential to select materials with a high affinity and selectivity for target analytes. However, the sorption capacity of adsorbents is usually limited, and the description of adsorption/desorption kinetics of analytes to adsorbents is complex. Typically, the adsorbent materials used in passive samplers are similar to those used in solid-phase extraction techniques. 

For the highly subcooled subset of Regime 2, (t, < ria), flow is singlephase (liquid), and integration of Eq. (26-93) gives what is commonly referred to as the orifice equation ... 

So, when r s > list (low subcooling, flashing before the choke print), use the compressible solution, Eq. (26-95) with T sp = Is- Otherwise (for high subcooling, no flashing before the choke point), use the liquid orifice equation, Eq. (26-94k... 

To simplify the nomograph, the flow area is converted to a nominal pipe diameter. For cases of low pressure drop or high subcooling, it may be necessary to size the condensate line based on the liquid velocity. Generally, a velocity of 3 ft/s is acceptable. 

A time averaging method was used in order to reduce wild pressure oscillations. In order to avoid non uniform distribution of coolant fluid only subcooled liquid entered the inlet manifold. Furthermore the engineering rule that the manifold diameter should be at last five times greater than the channel hydraulic diameter to equalise the fluid distribution was used. However, even if non uniform distribution occurs it will not affect the inlet and outlet measurements which are performed outside of the manifolds and it should not affect the local temperature measurements because of the averaging of wall temperatures across the N channels due to the very high thermal conductivity of the aluminium. 

Boiling also will occur with a liquid that is below its saturation temperature if the hot surface temperature is sufficiently above the nucleation temperature for the surface. The bubbles thus formed collapse quickly when they move from the surface into the bulk subcooled liquid, resulting in high heat-transfer rates. Moderate subcooling at the entrance to a vaporizer can be assumed to be heated by heat transfer at the same rates as for the saturated boiling process, if the saturation temperature of the fluid at the existing pressure is used in the temperature difference. 

In the case of the subcooled liquid, which involves an extrapolation into the solid region, the vapor pressure is usually so low that the fugacity coefficient is. close to unity, and the fugacity of this hypothetical liquid is equal to the extrapolated vapor pressure. For the supercritical liquid, however, the extrapolation is above the critical temperature of the liquid and yields very high vapor pressures, so that the fugacity of this hypothetical liquid is equal to the product of the extrapolated vapor pressure and the fugacity coefficient (which is taken from the corresponding-states plot of Fig. 

Ullman and Letan [189] studied the effect of noncondensable gas on condensation of bubbles in a subcooled liquid. Bergles and Bar-Cohen [190] provide information on the use of direct contact condensation of bubbles in a so-called submerged condenser. Zangrando and Bharathan [191] established computer models to characterize direct contact condensation of low-density steam (with high noncondensable gas concentrations) on seawater. 

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