Particulate Fouling and its Effect on U-Tube Steam Generator Thermal Performance

A multiple-node SIMULINK model of a U-tube steam generator (UTSG) has been developed so as to simulate the UTSG dynamics or responses to various defects, including fouling. UTSG responses to different events, such as reduced heat transfer area, change in heat transfer coefficient at different axial nodes, change in tube material conductivity, and the change of steam valve coefficients have been studied using the SIMULINK model. Then a mathematical model is established and implemented on MATLAB based on a systematic literature review on steam generator and heat exchanger fouling. Finally, the fouling model and the UTSG-SIMULINK model are both used to study the progress of tube fouling and the effects on UTSG thermal performance. The simulation results show the validity of the developed models. The developed models can be used to predict the degradation of UTSG thermal performance and hence provide guidance for plant maintenance planning. They can also be used to generate data for UTSG fault diagnosis. The results of these studies on the various defects and their effect on steam generator thermal performance are described.