The potential industrial applications of curved tubes for single- and two-phase flow are reviewed within the context of physics of flow, trends in the development of technology, and its laboratory to industrial-scale commercialization. Comparison of the performance of curved tube configurations demonstrates its edge over the conventional motionless mixers, heat exchangers, and reactors. Alongside, their respective advantages and limitations are also highlighted. Further, a compendium of the available correlations for single- and two-phase friction factor and heat- and mass-transfer coefficient in curved tubes has also been presented. Key issues regarding the design parameters governing the performance of the curved tubes for mixing and heat- and mass-transfer that impact the research, development, and scale-up or scale-down of such devices are also analyzed. Emerging trends for the development of a new class of curved tubes, namely, inverters and serpentine and chaotic devices are also presented.

A Review on the Potential Applications of Curved Geometries in Process Industry

Providing a comprehensive introduction to the fundamentals and applications of flow and heat transfer in conventional and miniature systems, this fully enhanced and updated edition covers all the topics essential for graduate courses on two-phase flow, boiling, and condensation. Beginning with a concise review of single-phase flow fundamentals and interfacial phenomena, detailed and clear discussion is provided on a range of topics, including two-phase hydrodynamics and flow regimes, mathematical modeling of gas-liquid two-phase flows, pool and flow boiling, flow and boiling in mini and microchannels, external and internal-flow condensation with and without noncondensables, condensation in small flow passages, and two-phase choked flow. Numerous solved examples and end-of-chapter problems that include many common design problems likely to be encountered by students, make this an essential text for graduate students. With up-to-date detail on the most recent research trends and practical applications, it is also an ideal reference for professionals and researchers in mechanical, nuclear, and chemical engineering.

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Two-phase flow, boiling and condensation in conventional and miniature systems

Convective boiling heat transfer and two-phase flow characteristics inside a small horizontal helically coiled tubing once-through steam generator

A review on the two-phase heat transfer characteristics in helically coiled tube heat exchangers

Two-phase friction pressure drop and heat transfer coefficients in a once-through steam generator with helically coiled tubes were investigated with the model test rig of an integrated type marine water reactor. As the dimensions of the heat transfer tubes and the thermal-fluid conditions are almost the same as those of real reactors, the data applicable directly to the real reactor design were obtained. As to the friction pressure drop, modified Kozeki's prediction which is based on the experimental data by Kozeki for coiled tubes, agreed the best with the experimental data. Modified Martinelli-Nelson's prediction which is based on Martinelli-Nelson's multiplier using Ito's equation for single-phase flow in coiled tube, agreed within 30%. The effect of coiled tube on the average heat transfer coefficients at boiling region were small, and the predictions for straight tube could also be applied to coiled tube. Schrock-Grossman's correlation agreed well with the experimental data at the pressures of lower ...

https://www.tandfonline.com/doi/pdf/10.1080/18811248.1982.9734239

Friction pressure drop and heat transfer coefficient of two-phase flow in helically coiled tube once-through steam generator for integrated type marine water reactor.

A Study of Helically-Coiled Tube Once-Through Steam Generator

The hydraulic instability is one of the impermissible evil in the operation of BWR. And there has been no effective way preventing from it, because its mechanism is not clarified yet. The authors made many experiments with an electrically heated natural-circulation-loop, which is equipped with an electric condenser type void-meter. As a result, they conclude that the hydraulic instability is a kind of non-linear oscillation caused by the combination of the fluid kinetics in the heating section and the non-linearity of the friction loss of the two-phase flow. They also derive analytically a block diagram of the circulation loop, in which the kinetics of each section are simulated with simple linear transfer functions except the term of friction loss. The solutions, calculated by an analog computer, coinside well with the experimental results.

Kenji Kurosu

Papers

A Study of Helically-Coiled Tube Once-Through Steam Generator

Hydraulic Instability in Boiling Water Reactors