Modification of the dominant flow criteria in the thermal evaluation of air-cooled condenser

Abstract

The current project of Biomass Power Plants in the sugar industry of Cuba, has as limitation the access to the water required for condensation. A possible solution would be the use of air-cooled condenser (ACC), however, the thermal assessment of a ACC is imprecise since the available methods are in extreme complex and do not characterize adequately the overall heat transfer coefficient (K), being required the use of excesses of heat transfer surface, which increments costs of the facilities. The objective was to develop a valid model for any zone of operation and regimen of flow that computes the coefficient K with a smaller index of dispersion than the available models.The current status of the thermal analysis in an ACC and the methods used for each zone of operation, characteristics and limitations are shown. A differential and correlation analysis to obtain a single model, which is just for the four zones of dominant flow, was made. In the validation it is verified that the proposed model correlates with an average error of  in 88.7% of available experimental data, reducing in a third part the errors of the current methods used. This work shows that the use of the dominant flow criteria enables reducing the indexes of uncertainty in the thermal evaluation of the ACC, which derive in a larger reliability in the assessment analysis and eludes the use of excesses of heat transfer surface due to a low reliability in the thermal analysis.