International Journal of Multiphase Flow, Vol.24, No.2, 189-210, 1998
Heat transfer in intermittent air-water flows - Part II - Upward inclined tube
This paper presents a study on the heat transfer in intermittent air-water flows in an upward inclined tube. The experimental technique is based on infrared thermography of an electrically heated wall of the tube, providing both visualization of the temperature held and measurements of the local wall temperature. Local heat transfer coefficients and how parameters have been measured for air-water flow in a pipe of 49.2 mm inner diameter at inclination angles of 2 degrees and 5 degrees. The water and air Froude numbers varied from 0.59 to 2.0 and from 0.03 to 0.57, respectively. Experimental correlations of the heat transfer coefficient indicate that the liquid and gas Froude numbers and dimensionless frequency of bubble appearance are good correlating parameters. A simple physical model was developed to correlate between the flow parameters and the heat transfer.
Keywords:GAS-LIQUID FLOW;PIPE