Heat Transfer during Annular Flow Condensation of Steam inside Tubes

Effects of Rib Shapes on Heat Transfer Characteristics of Turbulent Flow of Al2O3-Water Nanofluid inside Ribbed Tubes

In this paper, convection heat transfer of Al2O3-water nanofluid turbulent flow through internally ribbed tubes with different rib shapes (rectangular, trapezoidal and semi-circular) is numerically investigated. For each rib shape, the optimum geometric ratio and volume fraction were calculated using entropy generation minimization technique. The governing equations in...

Two Phase Flow Patterns During Condensation of Steam in Micro-Tubes

Flow visualization of two phase flow pattern of steam during condensation process in separate horizontal quartz micro-tubes with inner diameter ranging from 70-675 m was conducted. Two main kinds of flow patterns were observed: annular flow and slug flow, which both were nearly symmetrical. The annular flow also can be divided into two kinds: annular flow and annular-wave flow. The effects of t...

Condensation Heat Transfer of Pure Refrigerants in Microfin Tubes

Heat Transfer and Pressure Drop During HC-600a (Isobutane) Condensation Inside a Brazed Plate Heat Exchanger

This paper presents the heat transfer coefficients and the pressure drop measured during HC-600a (Isobutane) condensation inside a brazed plate heat exchanger: the effects of saturation temperature, refrigerant mass flux and vapour super-heating are investigated. The heat transfer coefficients show weak sensitivity to saturation temperature and great sensitivity to refrigerant mass flux. At low...

Simplified Correlation Equations of Heat Transfer Coefficient During Phase Change Flow Inside Tubes Filled with Porous Media

In this work an easy to use, simple and direct equations were formulated and tested. Heat transfer coefficients of phase change fluid flow were examined in this work. The considered fluid flow encountered convection heat flux inside rigid tubes filled with porous media. During the flow, phase change was assumed. Experimental work was conducted using Carbon dioxide as fluid. An analytical method...