Anti-freezing And Numerical Investigation Of600MW Direct Air-cooled Units

Direct air-cooled system has good heat transfer characteristics economy and saving environmental protection, especially used more widely in the power plant in Northwest China. But the air-cooled condenser direct air-cooling system directly in the ambient atmosphere, environmental factors affecting its performance and greater security, especially in the cold winter prone to freezing phenomenon, leading to damage to the air-cooled condenser, and even lead to air cooling unit outage, seriously affecting the safe operation of the unit. Firstly, brief introduction of direct air cooling system and analyzes the mechanisms and causes of air-cooling system to freeze and then under a600MW power plant air-cooled condenser unit infrared analysis of the prone figure frozen parts. Air cooling system fan base for the operation and regulation of the optimization of reference and to provide the basis for winterizing Direct Air Cooling unit.Flat serpentine finned tube heat exchanger as a condenser basic structural units, two-phase flow characteristics of the tube directly affects the performance of the condenser. In order to get distribution and heat transfer coefficient of variation along the tube wall of the inner tube of the steam condensate liquid, under a single flat major by building physical and mathematical models of the finned tube gas-liquid flow, and the typical working conditions in this paper, finned tubes for flat serpentine tube vapor flow and condensation heat transfer were studied, and numerical simulations related to the heat transfer coefficient thus combining theory was validated conclusions drawn two-phase flow engineering design and safe operation of the air-cooled condenser has a guiding role.