Liquid coolant

For areas where cooling water is either scarce or not available, direct liquid injection may be a possibility. The liquid coolant should be injected near the discharge end of the compressor to minimize lubricant dilution. Alternatively, the liquid can be flashed in a separate exchanger and used to cool the lubricant. While the cooling may appear to decrease the power to the compressor, the net effect is an increase in the power due to the additional weight flow of the extra refrigerant needed to perform the cooling. 

Many manufacturers, users, and compressor applications still require that compressor cylinders be supplied with liquid-cooled cylinders. Figure 11-21 includes schematics of several types of liquid coolant systems. 

Table 2.5 Saturation thermophysical properties of some liquid coolants at 1 bar...

Mohapatra S, Loikitis D (2005) Advances in liquid coolant technologies for electronics cooling. 

Consider a flow of liquid coolant in a capillary where heating and evaporation occur. The conditions on the interface are expressed by means of the continuity of the mass and thermal fluxes and the equilibrium of all acting forces (Landau and Lifshitz 1959) ... 

Reviews of analytical methods for impurities in alkali metals are largely devoted to Na and K owing to their use as liquid coolants in fast-breeder nuclear reactors ". These methods may be extended to Rb and Cs except the analysis for oxygen. In analytical work with the alkali metals, care is necessary during sampling and handling to avoid contamination in transit. The impurities usually considered are O, C, N, H and metals. 

Because the melting point of sodium metal is about 98° C (a bit lower than the boihng point of water), it is heated into a liquid phase and then transported in rail tank cars, where it cools and solidifies. When it arrives at its destination, heating coils in the tanks warm it back to the liquid stage, and it is then stored for use. Because sodium has a high specific heat rating, a major use is as a liquid coolant for nuclear reactors. Even though sodium (both solid and liquid) is extremely reactive with water, it has proven safe as a coolant for nuclear reactors in submarines. 

The simple glycols are used in antifreeze solns for automotive cooLing systems, commercial refrigerators etc. A.s liquid coolants, they are used in aircraft engines, machine... 

The design value of the overall heat transfer coefficient U between the process gas and the liquid coolant used in Chapter 5 was 142 J s-1 K-1 m-2. The resulting temperature profile is shown at the top of Figure 6.40. There is a sharp peak that occurs very near the inlet end of the reactor. This peak temperature is only about 5 K higher than the coolant because of the large value of U. In order to be able to demonstrate the use of a peak temperature controller, the value of U is drastically decreased to 14.2 J s-1 K-1 m-2, which changes the temperature profile to that shown at the bottom of Figure 6.40. Now the... 

P/ACE MDQ Methods Temperature control of capillary column with rapidly Development System recirculating liquid coolant. Selectable temperature control... 

Foam-insulated containers are adequate for some slush baths, but will require more effort to maintain the coolant. Foam-insulated containers should never be used for long- or short-term storage of cryogenic liquids. They may be used for cryogenic liquid transport, but there will be significantly more loss of the liquid coolant (even in limited transport) than from a regular Dewar. 

Contact condensers employ liquid coolants, usually water, which come in direct contact with condensing vapors. These devices are relatively uncomplicated, with typical configurations illustrated in Figure 14. Some contact condensers are simple spray chambers, usually with baffles to ensure adequate contact. Others, incorporate high-velocity jets designed to produce a vacuum. 

FIG. 11-62 Vibratory -conveyor adaptations as indirect heat-transfer equipment, a) Heavy-duty jacketed for liquid coolant or high-pressure steam, h) Jacketed for coolant spraying, (c) Light-duty jacketed construction, d) Jacketed for air or steam in tiered arrangement. e) Jacketed for air or steam with Mix-R-Step surface. Courtesy of Jeffrey Mfg. Co.)... 

Dangerous when heated it emits highly toxic fumes of Na20 and K2O. Used as a liquid coolant for nuclear reactor cores. See also SODIUM and POTASSIUM. 

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