Proposta e comparação de um modelo fenomenológico com base em alto transporte de massa e supersaturação para torre de resfriamento de água. / Presentation and comparison of a model based in high mass transfer and supersaturation in a cooling water tower.

AUTOR(ES)
FONTE

IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia

DATA DE PUBLICAÇÃO

20/12/2011

RESUMO

Cooling towers are equipment widely used in industrial plants, where these operate under severe conditions such as cooling water inlet temperatures above 50oC. Under this condition, there are high evaporation of water and high mass transfer, generally not considered in performance analysis of a cooling tower. This work presents and analyzes the differences between the proposed model and the Merkel and Poppe approaches. The proposed model in this work is based on differential equations for energy and mass balances and on the mechanisms of combined heat and mass transfers, at high mass transfer condition and considering the supersaturated air from the height of the tower that the excess of water vapor condenses as a mist. At the point that the air became supersaturated, the differential equations for energy and mass balances start to consider the supersaturation phenomena. The mathematical model developed in this work is composed by ordinary differential equations and auxiliary equations which were solved at Matlab. The parameters investigated were water and air mass flow rates, air wet bulb temperature, water inlet temperature and tower height. The results of air and water temperatures, humidity air across the tower height are presented for each method analyzed.

ASSUNTO(S)

cooling tower heat transfer mass transport supersaturação supersaturation torres de resfriamento transporte de calor transporte de massa

ACESSO AO ARTIGO

Documentos Relacionados