Enhanced power plant air-cooled condensers using auto-fluttering reeds

Highlights: • Evaluated the use of auto-fluttering reeds in air-cooled power plant condensers. • Measured pressure drop and heat transfer in reed-enhanced heat exchanger. • Showed effect of reeds on power-plant efficiency. • Conducted geometric optimization to maximize efficiency with and without reeds. • Optimized condensers improve power-plant efficiency by ~1.38%. Air-cooled condensers offer a pathway to decreasing the water consumption associated with electricity production, but dry-cooled plants suffer from lower efficiencies than those of conventional systems. One approach to increasing the performance of air-cooled condensers is to employ heat transfer enhancement techniques. Many enhancement devices have been proposed, but they have not been evaluated in air-cooled condensers at relevant scales. One promising low-cost air-side enhancement approach is the use of auto-fluttering reeds, which increase the vorticity of the flow and result in higher heat transfer coefficients. This work investigates the use of auto-fluttering reeds in a dry-cooled Rankine cycle power plant experimentally and numerically. The experimental results quantify the pressure drop and heat transfer characteristics of the enhanced condensers, which are then incorporated into a detailed model to assess performance at the system level. The air-cooled condenser geometry is also optimized to determine the maximum efficiency with and without the reeds. The results show that auto-fluttering reeds could improve the system performance in retrofit applications and may have some economic benefits in new dry-cooled power plants.