Numerical Modeling and Exergy Analysis of Flue Gas Injection into Heller Tower on The Operation of Gas and Steam Turbines of a Combined Cycle Power Plant under Crosswind Conditions

The performance of dry cooling tower (Heller Type) is highly affected by environmental conditions, especially wind condition. Under wind conditions, due to the loss of symmetry of the distribution of pressure around the tower, as well as the wind covering phenomenon on the top of the tower, the inlet airflow to the tower and so the efficiency of the cooling tower decreases. One of the methods recently proposed to improve cooling tower performance under wind conditions is the flue gas injection from a recovery boiler, which is about 130oC, into the cooling tower at combined cycle power plants. In the present study, a Heller dry tower, with a solution domain around it, is modeled using computational fluid dynamics. The amount of numerically calculated heat released from the cooling tower, with and without injection at the design conditions of the tower under crosswind effect, has been used to perform an exergy analysis on the components of the combined cycle power plant. Finally, the positive and negative effects of flue gas injection into the Heller Tower have been studied on the overall performance of the combined cycle power plant, indicating an increase about 0.94% and 0.88% in the overall first and second law efficiencies of combined cycle power plant respectively.