A mathematical model of low-head oxygenators

A mathematical model is presented that predicts the performance of low-head oxygenators (LHO). Experimentally determined values of G(20) for a single hole in a flooded orifice plate were used as the basis to develop a mathema tical model that can be used to predict LHO performance under a variety of design and operating conditions. Model predictions were compared to two pub lished studies. The model predicted the published data for dissolved oxygen levels in the departing affluent within 2-3%, oxygen absorption efficienci es within 5-6%, and total gas pressures within 1%. The mathematical model i s thoroughly developed including an analysis of numerical stability and nec essary restrictions to assure stability and accuracy. Convergence based sol ely upon effluent values was not sufficient to produce accurate results, bu t required additional criteria of requiring a minimum number of chamber flu shings prior to convergence checking. The model was used to demonstrate its utility in predicting the effects of G/L ratio on gas absorption efficienc y, effluent gas conditions and the effects of number of LHO chambers used. This model allows the designer or operator of an LHO to easily make design and operational decisions by modifying the input parameters and observing t he exit conditions and performance indicators. (C) 2001 Elsevier Science B. V. All rights reserved.