Heat transfer in nucleate boiling outside horizontal tube bundles. 2nd report Prediction for tube bundle effect.

Saturated Flow Boiling Heat Transfer in Horizontal Square Tube

Flow Boiling Heat Transfer of Binary Mixtures HFO1234yf/R32 in a Smooth Horizontal Tube

HFO1234yf is a promising alternative for automobile air conditioners because of its low GWP of 4 and thermophysical properties similar to those of R134a. However, its performance is inferior to R410A. This makes it difficult to be applied to residential air-conditioners. A mixture of HFO1234yf and R32 is expected to balance both the GWP and COP requirement when applied to residential air-condit...

Heat Transfer Efficiency of Turbulent Film Boiling on a Horizontal Elliptical Tube with External Flowing Liquid

Film boiling on a horizontal elliptical tube immersed in external flowing nitrogen liquid is investigated in the present paper. The isothermal wall temperature is high enough to induce turbulent film boiling, and then a continuous vapor film runs upward over the surface. The high velocity of the flowing saturated liquid at the boundary layer is determined by potential flow theory. In addition, ...

Heat transfer in nucleate pool boiling of multicomponent mixtures

Steady state pool boiling heat transfer coefficients have been obtained experimentally for acetone–isopropanol–water and acetone–MEK (methyl ethyl ketone)–water ternary systems. The data show that, for a given heat flux, the heat transfer coefficients of mixtures are lower than those obtained for pure components constituting the mixture. The measured heat transfer coefficients were compared wit...

Water-Heated Pool Boiling of Different Refrigerants on the Outside Surface of a Horizontal Smooth Tube

Pool boiling heat transfer has been extensively studied over decades, but the effect of boundary heating conditions on boiling received little attention. In this work, heat transfer coefficients during pool boiling of five different refrigerants (R123, R245fa, R236fa, R134a, and R22) on the outside surface of a smooth copper tube were measured at the saturation temperature of 6.7 C; water flows...