Detail publikace

Influence of Underpressure on Heat Transfer And Temperature Field at Sprinkled Tube Bundle

KRACÍK, P. POSPÍŠIL, J.

Originální název

Influence of Underpressure on Heat Transfer And Temperature Field at Sprinkled Tube Bundle

Typ

článek v časopise - ostatní, Jost

Jazyk

angličtina

Originální abstrakt

Sprinkled tube bundles with a thin liquid film flowing over them are used in various technology processes where it is necessary to separate the vapour and liquid phases quickly and efficiently at low temperatures with a corresponding decrease of pressure around the tube bundle. In ideal conditions water boils at the whole surface of an exchanger, but in practice it must be considered that in original spots of contact between water and the exchanger wall the water will not boil at the tubes' surface but the cooling liquid will merely be heated-up. The article focuses on these processes. Experiments have been carried out at a tube bundle consisting of copper tubes of 12 mm diameter placed horizontally one above another that have been heated by water of an average input temperature approx. 40 °C. This bundle has been sprinkled by cool water at temperature of 15 °C and pressure has been gradually decreased using an exhauster at constant flow rates of heating and falling film liquid inside an experimental device's chamber. Was tested flow of sprinkled liquid in the range of 4-9 liters per minute, which corresponds to the range of Reynolds numbers of about 300 to 600 [-]. The result of these experiments is a studied heat transfer coefficient at the surface of a sprinkled tube bundle during heating of the cooling liquid with a transition into boiling of the liquid at the bundle. At a flow of 8 liters per minute were acquired sequence thermal camera FLIR SC 660. After evaluation of the sequences were generated maps of the temperature field according to decreasing the pressure and its standard deviation. From the contour graphs can evaluate the thermal stability of the liquid film on the spray tube bundle.

Klíčová slova

sprinkled, heat transfer, non-boiling, tube bundle, under pressure

Autoři

KRACÍK, P.; POSPÍŠIL, J.

Vydáno

1. 4. 2016

Nakladatel

Trans Tech Publications

Místo

Switzerland

ISSN

1662-7482

Periodikum

Applied Mechanics and Materials

Číslo

832

Stát

Švýcarská konfederace

Strany od

200

Strany do

206

Strany počet

7

BibTex

@article{BUT122532,
  author="Petr {Kracík} and Jiří {Pospíšil}",
  title="Influence of Underpressure on Heat Transfer And Temperature Field at Sprinkled Tube Bundle",
  journal="Applied Mechanics and Materials",
  year="2016",
  number="832",
  pages="200--206",
  doi="10.4028/www.scientific.net/AMM.832.200",
  issn="1662-7482"
}