Explain with the help of diagram how heat is transferred in bubbly flow and annular flow?
Answers
Explanation:
Annular flow is the upward movement of a continuous gas phase in the center of the conduit with an annular film of liquid flowing upward between the central gas phase and the wall of the conduit, and with dispersed liquid droplets being lifted by the gas phase.
Explanation:
The effect of small gas phase additions on heat transfer in downward bubbly flow was shown. Data on the size of bubbles detaching from the edges of an array of capillaries in a liquid flow are given. The influence of the disperse phase dimensions on the heat transfer is discussed. The preliminary data of PIV investigation of liquid velocity distribution is also presented. It is shown that change in the size of the dispersed phase can lead to both intensification and deterioration of heat transfer as compared with a single-phase flow at constant flow rates of liquid and gas at the channel inlet. The mechanism of heat transfer intensification was described early. The cause of the heat transfer deterioration is turbulence suppression in the near-wall region.