Influence of non-steady transient heat flux on flow boiling heat transfer and pressure drop in horizontal pipes

Flow regime-based modeling of heat transfer and pressure drop in microchannel flow boiling

Local heat transfer coefficients and pressure drops during boiling of the dielectric liquid fluorinert FC-77 in parallel microchannels were experimentally investigated in recent work by the authors. Detailed visualizations of the corresponding two-phase flow regimes were performed as a function of a wide range of operational and geometric parameters. A new transition criterion was developed for...

Saturated Flow Boiling Heat Transfer in Horizontal Square Tube

Flow Boiling Heat Transfer and Pressure Drop of R1234ze(E) and R32 in a Horizontal Micro-Fin Tube

In the present study, the flow boiling heat transfer of R1234ze(E), R32 and zeotropic mixture R1234ze(E)/R32 (50/50 mass%) in a horizontal micro-fin tube is experimentally investigated to clarify the pressure drop and heat transfer characteristics. Tested micro-fin tube is made of copper, and its geometry is as follows, 6.00 mm in outer diameter, 5.21 mm in mean inside diameter, 0.26 mm in fin ...

Non-Boiling Heat Transfer in Gas- Liquid Flow in Pipes – a Tutorial

In this tutorial the fundamentals of non-boiling heat transfer in two-phase twocomponent gas-liquid flow in pipes are presented. The techniques used for the determination of the different gas-liquid flow patterns (flow regimes) in vertical, horizontal, and inclined pipes are reviewed. The validity and limitations of the numerous heat transfer correlations that have been published in the literat...

The Effect of Linear Change of Tube Diameter on Subcooled Flow Boiling and Critical Heat Flux

One of the major industry problems is the flow boiling, where reaching to the critical heat flux (CHF) condition can lead to a temperature jump and damage of the systems. In the present study, the effects of a uniform change in tube diameter on subcooled flow boiling and CHF was numerically investigated. The Euler-Euler model was used to investigate the relationship between the two liquid and v...