Heat-transfer equipment, condensers

These properties, coupled with the metal s ability to promote bubble-type vapour formation on the surface when heating liquids, and dropwise condensation when condensing vapours, make the metal an ideal constructional material for heat-transfer equipment for use with strong acids. 

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... 

If the optimum size heat exchanger for the initial plant is installed, an additional exchanger either in parallel or in series will be required when the plant is expanded. This may be the best option when the heat transfer involves condensation and subcooling. The exchanger can be designed to perform both functions initially, and then when the plant is expanded an aftercooler can be installed and the initial equipment can act only as a condenser. 

Carey, Liquid-Vapor Phase-Change Phenomena An Introduction to the Thermophysics of Vaporization and Condensation Processes in Heat Transfer Equipment... 

Ihe values of the film coefficients of heat transfer h, and accordingly those of the overall coefficient U, vary by orders of magnitudes, depending on the fluid properties and on whether they undergo phase change, that is, condensation or boiling. Thus, the correct estimation of U is very important in the design of heat transfer equipment. 

The first consideration when designing or evaluating heat transfer equipment is as to which side of the heat transfer wall the controlling heat transfer resistance will exist on. for example, when air is heated by condensing saturated steam, the air-side film coefficient may be 30 kcal h m -°(E, while the steam-side film coefficient might be on the order of 10 000 kcalh m" °C . In such a case, we need not consider the steam-side resistance. The overall coefficient would be almost equal to the air-side film coefficient, which can be predicted by... 

Boiling and condensation phenomena are very complicated, as we have shown in the preceding sections. The equations presented in these sections may be used to calculate heat-transfer coefficients for various geometries and fluid-surface combinations. For many preliminary design applications only approximate values of heat flux or heat-transfer coefficient are required, and Tables 9-4 to 9-6 give summaries of such information. Of course, more accurate values should be obtained for the final design of heat-transfer equipment. 

Condensation. See Sec. 10, Heat Transmission Sec. 11, Heat-Transfer Equipment and Sec. 12, Evaporative Cooling. For direct-... 

Carey, V. P. (1992) Liquid-Vapor Phase-Change Phenomena An Introduction to the Thermophysics of Vaporization and Condensation Processes in Heat Transfer Equipment, in Series in Chemical and Mechanical Engineering, G.F. Hewitt and C.L. Tien, Editors, Taylor Francis Series, Hemisphere Pub. Corp., Washington, D.C., p. xvii, 645. 

David Johnsori/ P E / M S C E Heat Exchanger Specialist, AAmerican Institute of Chemical Engineers American Society of Mechanical Engineers API Subcommittee on Heat Transfer Equipment API 660/1SO 16812, API 661/lSO 13706, API 662/lSO 15547 (Thermal Design of Heat Exchangers, Condensers, Reboilers)... 

Functional Definitions Heat-transfer equipment can be designated by type (e.g., fixed tube sheet, outside packed head, etc.) or by function (chiller, condenser, cooler, etc.). Almost any type of unit can be used to perform any or all of the Usted functions. Many of these terms have been defined by Donahue [Pet. Process., 103 (March 1956)]. 

The objective of this subsection is to present the most important condensation correlations for design of heat transfer equipment. 

Nosetani, T., Sato, S. and Onda, K., 1981, Effect of marine biofouling on the heat transfer performance of titanium condenser tubes, in Somerscales, E.F.C. and Knudsen, J.C. eds. Fouling in heat transfer equipment. Hemisphere Publishing Corp. Washington, 345 - 353. 

Heat-transfer equipment in the form of heat exchangers and condensers is a vital part of the chemical process industries. Heat exchangers are used for the cooling or heating of all sorts of process materials, while condensers are used largely for the condensation of vapors from evaporators and consequent production of vacuum, and for the recovery of materials volatilized from stills. 

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