Reduced order analysis of flow and heat transfer for air-cooled condenser of power generating unit

摘要

The flow and heat transfer exhibit complex non-linear characteristics for the air-cooled condenser (ACC) of power generating unit because numerous factors, including the meteorological and the geographic conditions, as well as the configurations of wavy finned tube bundles, can affect its performances. In order to quickly and accurately predict the air side velocity and temperature fields of ACC, the reduced order models (ROMs) based proper orthogonal decomposition (POD) method were established, by which the previous 10~5 DOF in CFD model was reduced to 10~1 DOF for new case prediction. The weight coefficients for POD modes were obtained by cubic spline interpolation and flux matching procedure (FMP). The air flow fields and correlating temperature fields influenced by environmental natural winds were revealed. It is found that accuracies of the POD solution with cubic spline interpolation are better than that of FMP. However, the FMP procedure, which can extract flow and thermal information from fewer observations, has better robustness than interpolation method. Hence, it is more appropriate for the POD solution of extrapolated cases. The present research may provide a rapid and reliable approach for the optimization of real-time operation of air-cooled power generating units.