Navigation by alphabet

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Lamella heat exchangers, Laminar flow: Laminar flow control, of boundary layers, Lancaster, J F, Langelier index for water quality, Large eddy simulation, in prediction of turbulent boundary layers, Laws for turbulent flows: Layers of fluid, free convection heat transfer in, Le Fevre equations for free convective heat transfer, Leakage between streams, in shell-and-tube heat exchangers Leakage effects, on heat transfer and pressure drop in shell-and-tube heat exchangers, Leaks, in heat exchanger, sealing by explosive welding, Lebedev, M E, Lee and Kesler equation, for vapour pressure, L-footed fins, Lessing rings, characteristic of, as packings for fixed beds, Li equation, for critical temperature of mixtures, Lienhard and Dhir analysis of critical heat flux in pool boiling, Lienhard and Eichhorn criterion, for transition in critical heat flux mechanism in crossflow over single tube,
Boiling Outside Tubes and Tube Bundles
Lift force: Liley, P E, Limb, D, Limpet coils: Linnhoff, B, Liquefaction, exergy analysis of, Liquid fluidized beds, Liquid fuels, properties of, Liquid hold-up, Liquid-liquid-gas flow, Liquid-liquid flow, Liquid metals: Liquid sheets, in direct contact heat transfer, Liquid-solid interfaces, fouling at, Liquids: Lister, D H, Local conditions hypothesis, for critical heat flux in flow boiling, Lockhart and Martinelli correlations: Lodge's rubberlike liquid (non-Newtonian), Logarithmic law region, Logarithmic mean temperature difference Longitudinal flow and heat transfer in tube banks, Long-tube vertical evaporator, Loss coefficient, Lost work in unit operations/exergy analysis, Louvered fins, in plate fin exchangers, Low-alloy steels: Low-finned tubes: Low-nickel steels, Lubricants, physical properties: Lucas methods

Index

HEDH
A B C D E F G H I J K L
Lamella heat exchangers, Laminar flow: Laminar flow control, of boundary layers, Lancaster, J F, Langelier index for water quality, Large eddy simulation, in prediction of turbulent boundary layers, Laws for turbulent flows: Layers of fluid, free convection heat transfer in, Le Fevre equations for free convective heat transfer, Leakage between streams, in shell-and-tube heat exchangers Leakage effects, on heat transfer and pressure drop in shell-and-tube heat exchangers, Leaks, in heat exchanger, sealing by explosive welding, Lebedev, M E, Lee and Kesler equation, for vapour pressure, L-footed fins, Lessing rings, characteristic of, as packings for fixed beds, Li equation, for critical temperature of mixtures, Lienhard and Dhir analysis of critical heat flux in pool boiling, Lienhard and Eichhorn criterion, for transition in critical heat flux mechanism in crossflow over single tube,
Boiling Outside Tubes and Tube Bundles
Lift force: Liley, P E, Limb, D, Limpet coils: Linnhoff, B, Liquefaction, exergy analysis of, Liquid fluidized beds, Liquid fuels, properties of, Liquid hold-up, Liquid-liquid-gas flow, Liquid-liquid flow, Liquid metals: Liquid sheets, in direct contact heat transfer, Liquid-solid interfaces, fouling at, Liquids: Lister, D H, Local conditions hypothesis, for critical heat flux in flow boiling, Lockhart and Martinelli correlations: Lodge's rubberlike liquid (non-Newtonian), Logarithmic law region, Logarithmic mean temperature difference Longitudinal flow and heat transfer in tube banks, Long-tube vertical evaporator, Loss coefficient, Lost work in unit operations/exergy analysis, Louvered fins, in plate fin exchangers, Low-alloy steels: Low-finned tubes: Low-nickel steels, Lubricants, physical properties: Lucas methods
M N O P Q R S T U V W X Y Z
L Lienhard and Eichhorn criterion, for transition in critical heat flux mechanism in crossflow over single tube,
Download the citation in the EndNote formatOpen in a new tab. Download the citation in the RefWorks formatOpen in a new tab. Download the citation in the BibTex formatOpen in a new tab.

Boiling Outside Tubes and Tube Bundles

DOI 10.1615/hedhme.a.000195

2.7 BOILING AND EVAPORATION
2.7.5 Boiling outside tubes and tube bundles

J. G. Collier and G. F. Hewitt

A. Boiling outside single tubes in cross flow

(a) Flow patterns

This section deals with the case where the flow past the tube or cylinder is by forced rather than by natural convection. This latter situation is dealt with in Section 192. Photographs presented by Vliet and Leppert (1962a) show very clearly the flow patterns that occur when nearly saturated water flows upward across a uniformly heated cylindrical tube. At moderate heat fluxes, typically around 20% of the critical heat flux, a vapor cavity forms in the cylinder’s wake. Initially this cavity is not continuous along the length of the cylinder, but as the heat flux is increased, the increase in the length of the cavity in the direction of flow results in the formation of a very uniform vapor sheet. An increase of velocity from 0.4 to 1.5 m/s or of tube diameter from 0.254 mm to 4.8 mm also results in a large stable vapor cavity behind the cylinder. Under these circumstances the only liquid reaching the top half of the cylinder is that which is supplied between the vapor bubbles and the heater surface as the bubbles enter the cavity wake near the horizontal diameter. For low heat fluxes, more liquid is supplied than evaporated and the excess is removed by entrainment in the cavity. The critical heat flux is reached when the liquid supplied in this manner becomes insufficient to cool the upper half of the cylinder.

In a parallel study, Vliet and Leppert (1962b) extended their work to include the effect of subcooled water flowing across the heated rod. For low subcoolings (< 16 °C), the flow pattern observed was similar to that for water at the saturation temperature. For greater subcoolings there is insufficient vapor to form a cavity in the wake of the cylinder because of the rapid condensation.

(b) Boiling heat transfer at heat fluxes lower than the critical heat flux

... You need a subscriptionOpen in a new tab. to view the full text of the article. If you already have the subscription, please login here

© 2024 by Begell House, Inc.