Condensate retention effects on the performance of plain-fin-and-tube heat exchangers: Retention data and modeling

A study of condensate retention is presented for plain-fin-and-tube heat exchangers typical to those used in air-cooling applications. An experiment in which the retained mass of air-side condensate was measured under dynamic conditions is described, and the results are analyzed using conventional thermal-hydraulic measurements of j and f. With the coupling between condensate retention and thermal performance established, a new model for predicting the mass of retained condensate is described and compared to the steady-state retention data. The model is successful in predicting retained condensate under relatively restricted conditions. The promise of this new approach, and possible refinements that will add engineering value are discussed.