Study of Non-condensable Gas, Fouling, and Plugging Effects on Condenser Performance Using NTU-Effectiveness Analytic Method and 2D Numeric Simulation

Abstract

This paper was objected to determine the effect and how sensitive the variation of the percentage of non-condensable gas, fouling thickness and the amount of plugging to the performance of the condenser and the steam turbine power output. This study was conducted using the NTU-effectiveness analytical method, and specifically for the study of the effects of non-condensable gas combined with numerical simulations to obtain the value of the condensation heat transfer coefficient as an input for analytical calculations. The study was conducted with a variation of the percentage of non-condensable gas 0% (new and clean), 2%, 5%, and 8%, with fouling thickness 0 µm, 2 µm, 5 µm, and 8 µm, and the amount of plugging 0%, 5%, 10%, and 15%. 2D numerical simulation was used to determine the impact of non-condensable gas percentage variation on the value of the condensation heat transfer coefficient on the outside of the tube, both qualitatively and quantitatively along the circumference of the condenser tube. The results of this study were, the greater the percentage of non-condensable gas, the thicker the fouling layer, and the more amount of plugging, would have an impact on decreasing the net turbine work. Consequently for new and clean conditions, the percentage of non-condensable gas were 2%, 5%, 8%, fouling thickness 2 um, 5 um, 8 um, and the amount of plugging were 5%, 10%, 15%, resulting in net turbine work to 202.55 MW, 192.08 MW, 189.08 MW, 185.85 MW (non-condensable gas), 200.05 MW, 196.01 MW, 192.08 MW (fouling), 195.2 MW, 185.27 MW, and 174.77 MW (plugging). A financial loss simulation was also carried out due to the decline in electricity sales affected by the decreasing of power plant’s net turbine work.