Two-phase flow through a staggered tube bundle of a shell and tube heat exchanger

Abstract

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.

Two-phase flow on the shell side of a shell and tube heat exchanger is complex. This paper contributes to the existing data base by presenting data for void fraction and pressure drops for tubes with a diameter of 19 mm. Results for air-water flows near atmospheric pressure are presented. The results were obtained for flows through a column of a thin-slice, staggered tube bundle containing 22 rows. It contained four full columns of tubes and two columns of half tubes placed on the shell walls. The tubes were 19 mm in diameter and 50 mm long with a pitch to diameter ratio of 1.32 and were arranged in a staggered triangular configuration. Previous studies have shown that the void fraction in a shell-side, gas-liquid flow becomes constant after only a few rows. Thus, the void fraction was only measured at one location. A gamma-ray densitometer was used to measure the void fractions. Corresponding pressure drops were obtained between rows 3 and 15. Data are presented for a mass flux range of 25-688 kg/m2s and a gas mass fraction range of 0.0005-0.6. The measurements are shown to compare reasonably well with correlations available in the open literature.