ISSN:0145-7632    

DOI:10.1080/01457638408962765

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The temperature difference between surface and deep water in the oceans represents a vast resource of thermal energy. A promising method of harnessing this resource is the open-cycle ocean thermal energy conversion (OC-OTEC) system, which utilizes steam evaporated from the surface water to power the turbine. In this paper the state of the art of heat and mass transfer related to evaporation and condensation of steam at low pressures in OC-OTEC is summarized and relevant research issues are discussed.

ISSN:0145-7632    

DOI:10.1080/01457638408962766

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This paper surveys the evolution of power condenser tube bundle arrangements and examines present-day designs. Condensation heat transfer during shell-side flow is reviewed, including the effects of vapor shear, condensate inundation, noncondensable gases, and enhancement techniques. The difficulties experienced in calculating vapor pressure drop through tube bundles are described, as well as recent attempts to obtain more reliable correlations. The modeling of these phenomena to predict shell-side condenser performance is reviewed, as well as the use of one- and two-dimensional computer codes. Appropriate topics for future research are identified.

ISSN:0145-7632    

DOI:10.1080/01457638408962767

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Major heat exchanger problems exist that provide opportunities for applied heat transfer research. Areas for research can be directed to dealing with problems that occur in four major categories: (1) performance and reliability problems: (2) economic recovery from tow temperature heat sources; (3) technological improvement in efficient recovery from high temperature sources: and (4) difficulties and high cost of realistic testing of new equipment.

ISSN:0145-7632    

DOI:10.1080/01457638408962768

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The mathematical problem of minimizing gross solids entrainment in an n-stage evaporator is formulated and solved using the method of Lagrange multipliers. The solution procedure enables direct comparison of the decontamination efficiencies of multistage evaporators as the number of stages (n) is varied. A numerical example is utilized to illustrate the method of solution. Equivalent expressions for batch distillation are also derived.

ISSN:0145-7632    

DOI:10.1080/01457638408962769

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A procedure has been developed to predict axial temperature distributions for the combustion gas. air, and walls of an annular radiation recuperator. It is based on using the zone method to treat radiation exchange between the combustion gas and its boundaries and on solving a system of nonlinear energy balance equations for the temperature distributions. The procedure may be used for a wide range of design and operating conditions, and parametric calculations have been performed to determine the effect of these conditions on recuperator performance.

ISSN:0145-7632    

DOI:10.1080/01457638408962770

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A hot stream of a very viscous fluid, such as a polymer, may be cooled in a heal exchanger consisting of multiple parallel passages. However, if a quite uniform temperature distribution is desired in the exit stream, the fluid flowing through each of the passages must be cooled to very nearly the same temperature. An analytical treatment of heat transfer and pressure drop in viscous flow between parallel plates during cooling reveals the operating conditions and passage geometry required to achieve this goal. Solution of the equation obtained depends only on the physical properties of the fluid and the cooler geometry. Non-Newtonian behavior of the fluid is approximated by a power-law function. A unique type of heat exchanger was designed on the basis of this analysis.

ISSN:0145-7632    

DOI:10.1080/01457638408962771

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Fouling in heat exchange equipment results in a significant energy toss by increasing heat transfer resistance and fluid frictional resistance. This paper deals with an effective way to monitor fouling and describes a potentially useful diagnostic approach for discriminating different types of deposit in situ. Information regarding deposit type would be useful in selecting an appropriate treatment procedure. Some cautions regarding the indiscriminate use of fouling factor or fouling resistance are also discussed.

ISSN:0145-7632    

DOI:10.1080/01457638408962772

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor