ISSN Online: 2377-424X
ISBN Print: 0-89116-559-2
International Heat Transfer Conference 8
HEAT TRANSFER IN A VERTICAL PIPE AT SUPERCRITICAL PRESSURE
摘要
In heat transfer to fluids with pressures slightly above the critical value effects are observed comparable to the phenomena of film boiling. For example, in a vertical pipe with an upward flow heated by a constant heat flux the heat transfer can decrease rapidly in the so called pseudocritical region causing a steep increase of wall temperature. Downstream of that region the heat transfer and the wall temperature return to usual values. It was determined from a numerical solution of the turbulent conservation equations that these effects are due to the influence of gravity on the velocity profile and the turbulence structure in the near wall region of the flow. The calculated results are compared to experiments and show qualitatively good agreement.