Subcooling

About: Subcooling is a research topic. Over the lifetime, 6150 publications have been published within this topic receiving 99125 citations.

Refrigeration cycle and method of controlling the same

Abstract: A refrigeration cycle comprises a compressor, an indoor heat exchanger, an outdoor heat exchanger, a liquid receiver; and a pressure reducer connected in series to form a closed loop. The liquid receiver and the pressure reducer connected in series are connected between the indoor heat exchanger and said outdoor heat exchanger. A non-azeotropic mixture refrigerant comprising at least two kinds of refrigerant of different boiling temperatures mixed together is charged in and circulated through the refrigeration cycle. The mixing ratio of the azeotropic mixture refrigerant circulated thorough the refrigeration cycle is controlled substantially constant.

A Parametric Study of Boiling Heat Transfer in a Horizontal Tube Bundle

Abstract: Boiling heat transfer outside of a section of a uniformly heated horizontal tube bundle in an upward crossflow was investigated using R-113 as the working fluid. The incline tube bundle had five columns and 27 rows with a pitch-to-diameter ratio of 1.3. Heat transfer coefficients obtained from the 14 instrumented tubes are reported for a range of fluid and flow conditions; slightly subcooled liquid inlet conditions were used. At most heat fluxes there was no significant variation in the local heat transfer coefficients throughout the tube bundle. However, at low heat fluxes and mass velocities, the heat transfer coefficient increased at positions higher in the tube bundle. As pressure and mass velocity increased so did the heat transfer coefficients. For the local heat transfer coefficient, a Chen-type correlation is compared to the data; the data tend to be overpredicted by about 20%. Reasons for the over-prediction are suggested.

Flashing flow of initially subcooled water in convergent--divergent nozzles

Abstract: Results from a research program conducted a number of years ago on the problem of flashing flow of water in nozzles are presented. In a previous paper results for the case of stagnation states in the low quality two-phase region were reported. The present paper reports results for stagnation states in the subcooled region at pressures up to 9.05 x 10/sup 3/ kN/m/sup 2/ and subcooling from 0 to 60/sup 0/C. Pressure profiles and flow rates are reported. The results are compared with limiting cases of Bernoulli flow (meta-stable liquid flow) and homogeneous equilibrium flow. As expected neither was able to predict the experimental results. A two-step model based upon nucleation delay, ''discontinuous'' transition to two-phase flow followed by frozen composition gave reasonable predictions of the flowrates and pressure profiles in the convergent section.

Critical Heat Flux of Steady Boiling for Subcooled Water Jet Impingement on the Flat Stagnation Zone

Abstract: An experimental investigation was carried out for predicting the critical heat flux (CHF) of steady boiling for a round subcooled water jet impingement on the flat stagnation zone. The experimental data were measured in a steady nucleate boiling state. Three main influencing parameters, i.e., subcooling, impact velocity and jet nozzle size were widely changed and their effects on the critical heat flux were systemically studied. An empirical correlation was obtained using the experimental data over a wide experimental range for predicting the critical heat flux of steady boiling for a round subcooled crater jet impingement on the flat stagnation zone

Method and plant for liquefying a gas with low boiling temperature

Abstract: Method of liquefying a mixture of gas rich in methane by performing an auxiliary cycle and a main cycle in which are used an auxiliary and a main refrigerating fluid of several components. In each cycle are performed the compression, cooling, liquefying and sub-cooling of the refrigerating fluids in counter-flowing relationship with themselves after expansion-vaporization in a heat exchanger. The gas to be liquefied is cooled in parallel with said main refrigerating fluid which has been pre-cooled in the auxiliary cycle. Pre-cooling of said gas is performed in an exchanger cooled by the refrigerating main fluid after its expansion-vaporization in said heat exchanging column of said main cycle and before its re-compression.