• Paddlewheel aerator performance was experimentally studied using variable paddle angles and surface areas. • Increasing paddle angle and surface area significantly enhanced dissolved oxygen transfer in water. • Maximum dissolved oxygen concentration (7.66 mg/L) was achieved at a 120° paddle inclination. • Power consumption peaked at 90° due to increased hydrodynamic resistance. • Highest energy efficiency (SAE = 72.33 kg O₂/kWh) was obtained with the largest paddle at 120°. Dissolved oxygen (DO) is crucial for the health of aquatic ecosystems, especially in freshwater. This study examines the effectiveness of paddlewheel aerators in increasing DO concentration in water. The primary objective is to evaluate how the angle and surface area of paddle influence the rate of oxygen dissolution. Experiments were conducted under controlled conditions using paddle angles of 60°, 90° and 120°, and paddle length-to-width ratios of 1.18, 0.94 and 0.27. Changes in DO concentration in water was measured and compared across all angle and surface area configurations. The results demonstrated that, the largest surface area (2302.8 mm²), combined with a 120° inclination angle, proved to be the most effective setup, produces the highest dissolved oxygen (DO) concentration (7.66 mg/L) and the maximum Standard Aeration Efficiency (SAE) of 0.117 kg O₂/kWh. This configuration also improved energy efficiency as reflected by the calculated SOTR and SAE values. These findings highlight the potential of paddlewheel aerators in improving DO in water, especially for aquaculture applications.
Saad et al. (Fri,) studied this question.