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

Nanoparticle deposition effects on the minimum heat flux point and quench front speed during quenching in water-based alumina nanofluids

Laminar flow and heat transfer in helically coiled tubes with substantial pitch

Observation of boiling structures in high heat-flux boiling

Visualization of boiling structures in high heat–flux pool-boiling

Heat Transfer and Pressure Drop in a Helically Coiled Rectangular Duct

Cooling passages are often used in the rotor windings of large electrical generators, where the flow channel rotates about an axis parallel to but displaced from its axis of symmetry. In such a rotating passage, Coriolis accelerations and density gradients caused by the heated wall lead to the development of secondary flows which can have strong effects on heat transfer and pressure drop characteristics. Finite difference solutions were obtained for laminar flow of air in a rotating rectangular duct with aspect ratio 2/1, where the duct wall is subjected to a uniform heat flux. The solutions show the effect of rotation on the development of the flow patterns and velocity and temperature variations. Results for Nusselt number and friction factor are presented in both the inlet and fully developed regions over a range of Grashof and Reynolds numbers.

Computation of Laminar Heat Transfer in Rotating Rectangular Ducts

Laminar Heat Transfer and Pressure Drop in a Rectangular Duct Rotating About a Parallel Axis

A finite-difference solution is presented for the entrance region laminar fluid flow and heat transfer in square ducts. The solution procedure uses two-dimensional computer storage and a marching technique to save computation costs. The results presented are in excellent agreement with other published axial velocity measurements. The lateral velocities do not exhibit the previously reported oscillatory behavior found near a diagonal. Temperature profiles and Nussdt number data in the thermal entrance region for Pr = 6.0 are presented.

Combined hydrodynamic and thermal development in a square duct

A 3 x 3 rod bundle with a heated shroud was developed to study post-critical-heat-flux (post-CHF) dispersed-flow boiling. The hot-patch technique was applied to a rod bundle, which successfully arrested the quench front at the test section inlet. Measurements included mass flux, wall heat flux, inlet equilibrium quality, wall temperatures along the bundle axis, and actual vapor temperatures upstream and downstream of a spacer grid. The vapor superheat (up to 600 /sup 0/C) increased with increasing wall heat flux and decreasing mass flux and vapor qualtiy. The heat partition ratio (fraction of total heat input that goes toward evaporation) was found to increase with increasing mass flux and decreasing inlet quality but remained essentially independent of heat flux. The results for the rod bundle were found to be in good agreement with trends previously reported for post-CHF heat transfer in single tubes.

S. Neti

Papers

Heat Transfer and Pressure Drop in a Helically Coiled Rectangular Duct

Computation of Laminar Heat Transfer in Rotating Rectangular Ducts

Laminar Heat Transfer and Pressure Drop in a Rectangular Duct Rotating About a Parallel Axis

Combined hydrodynamic and thermal development in a square duct

Parametric Trends for Post-CHF Heat Transfer in Rod Bundles