CT-15 Enhanced Tubeside Condensation Using Twisted Tape Inserts

Z. H. Yang

2001; rev 05/2018

This report describes a combined experimental and analytical study of enhanced condensation using twisted tape inserts over a wide range of geometries and operating conditions. HTRI tested three twisted tape inserts having various twist pitches in condensation of pure components and mixtures with and without noncondensable gases. Local heat transfer and pressure drop data were taken simultaneously on the Multipurpose Condensation Unit (MCU).

Our experimental data indicated that twisted tape inserts enhance mixing and reduce the condensing mass transfer resistance, thereby significantly improving the vapor-phase condensing coefficient. The average heat transfer enhancement ratio, defined as h_tape /h_plain, ranged from1.5 to 4. Pressure drop increased 2 to 12 times. From the experimental data, HTRI developed correlations for condensing heat transfer coefficients and two-phase pressure drops. These correlations helped establish guidelines for designing and rating tubeside condensers with twisted tape inserts.