Experimental Study of Condensation Heat Transfer in Tubes under Centrifugal Force

In this study, fluid flow during condensation in a tube under different gravity conditions is simulated by utilizing centrifugal force to offset gravitational effects. The role of fins, tube diameter, and steam quality on the two-phase flow pattern, temperature distribution, and pressure drop is investigated. The results show that gravity, tube diameter, and steam quality have a significant effect on the flow pattern. The flow characteristics were also significantly affected by the operating parameters, with undulating and laminar flow dominating, while bubbling flow emerges under specific conditions. In microgravity environments, as steam quality decreases, the temperature drop diminishes progressively compared to normal gravity conditions. Under normal gravity and low flow conditions, the average temperature of finned tubes increased by 7 °C to 16.4 °C relative to bare tube temperatures, and the pressure drop escalated by up to 56%. The introduction of fins notably enhanced heat transfer efficiency and facilitated a more uniform temperature distribution. However, this enhancement in heat transfer was accompanied by an increase in pressure drop due to the heightened resistance to fluid flow caused by the presence of fins. These experimental insights offer a deeper comprehension of fluid behavior under diverse gravity conditions and lay a scientific foundation for designing future thermal management systems.