Analysis of Heat and Mass Transfer in an Evaporative Cooler with Fully Wetted Channel

- Journal title : Transactions of the Korean Society of Mechanical Engineers B
- Volume 25, Issue 12, 2001, pp.1766-1775
- Publisher : The Korean Society of Mechanical Engineers
- DOI : 10.22634/KSME-B.2001.25.12.1766

Title & Authors

Analysis of Heat and Mass Transfer in an Evaporative Cooler with Fully Wetted Channel

Song, Chan-Ho; Lee, Dae-Yeong; No, Seung-Tak;

Song, Chan-Ho; Lee, Dae-Yeong; No, Seung-Tak;

Abstract

A theoretical analysis on the heat and mass transfer in an evaporative cooler is presented in this work. The evaporative cooler is modeled as a channel filled with porous media the interstitial surface of which is covered by thin water film. Assuming that the Lewis number is unity and the water vapor saturation curve is linear, exact solutions to the energy and vapor concentration equations are obtained. Based on the exact solutions, the characteristics of the heat and mass transfer in the evaporative cooler are investigated. The comparison of the cooling performance between the evaporative cooler and the usual sensible heat exchanger is also carried out. Obviously, the evaporative heat exchanger shows better cooling performance than the sensible heat exchanger. This is due to the latent heat of water vaporization, which results in apparent increases both in the interstitial heat transfer coefficient and the specific heat of the air stream in the evaporative cooler.

Keywords

Evaporative Cooler;Porous Media;Lewis Number;Wet Bulb Temperature;Water Film;

Language

Korean

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