Topic
Subcooling
About: Subcooling is a research topic. Over the lifetime, 6150 publications have been published within this topic receiving 99125 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, a two-stage multi-intercooling transcritical CO2 refrigeration cycle with ejectorexpansion device (MIERC) was investigated, where the vapor compression line includes two intercoolers, the first with external coolant (air or water) and the second one with cycle refrigerant.
77 citations
TL;DR: In this paper, the problem of steady film condensation outside a wedge or a cone embedded in a porous medium filled with a dry saturated vapor is investigated, where the condensate and the vapor are separated by a distinct boundary with no two-phase zone in between.
77 citations
TL;DR: In this paper, the authors investigated enhancements in nucleate boiling of FC-72 dielectric liquid on porous graphite and compared results with those on a smooth copper surface of the same dimensions (10 × 10mm).
77 citations
TL;DR: In this article, the authors investigated CO2 flow condensation heat transfer coefficients and pressure drop for 0.89mm microchannels at horizontal flow conditions at saturation temperatures of −15 and −25°C, mass fluxes from 200 to 800 kilograms, and wall subcooling temperatures from 2 to 4°C.
Abstract: CO2 flow condensation heat transfer coefficients and pressure drop are investigated for 0.89 mm microchannels at horizontal flow conditions. They were measured at saturation temperatures of −15 and −25 °C, mass fluxes from 200 to 800 kg m−2 s−1, and wall subcooling temperatures from 2 to 4 °C. Flow patterns for experimental conditions were predicted by two flow pattern maps, and it could be predicted that annular flow patterns could exist in most of flow conditions except low mass flux and low vapor quality conditions. Measured heat transfer coefficients increased with the increase of mass fluxes and vapor qualities, whereas they were almost independent of wall subcooling temperature changes. Several correlations could predict heat transfer coefficients within acceptable error range, and from this comparison, it could be inferred that the flow condensation mechanism in 0.89 mm channels should be similar to that in large tubes. CO2 two-phase pressure drop, measured in adiabatic conditions, increased with the increase of mass flux and vapor quality, and it decreased with the increase of saturation temperature. By comparing measured pressure drop with calculated values, it was shown that several correlations could predict the measured values relatively well.
77 citations
TL;DR: In this paper, a rigorous numerical solution of a theoretical model based on laminar boundary layer theory for pool film boiling heat transfer from a horizontal cylinder including the contributions of liquid subcooling and radiation from the cylinder was obtained.
Abstract: A rigorous numerical solution of a theoretical model based on laminar boundary layer theory for pool film boiling heat transfer from a horizontal cylinder including the contributions of liquid subcooling and radiation from the cylinder was obtained. The numerical solution predicted accurately the experimental results of pool film boiling heat transfer from a horizontal cylinder in water with high radiation emissivity for a wide range of liquid subcooling in the range of nondimensional cylinder diameters around 1.3, where the numerical solution was applicable to the pool film boiling heat transfer from a cylinder with negligible radiation emissivity. An approximate analytical solution for the theoretical model was also derived. It was given by the sum of the pool film boiling heat transfer coefficient if there were no radiation and the radiation heat transfer coefficient for parallel plates multiplied by a nondimensional radiation parameter similar to the expression for saturated pool film boiling given by Bromley. The approximate analytical solution agreed well with the rigorous numerical solution for various liquids of widely different physical properties under wide ranges of conditions.
76 citations