ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-472-4
ISBN Online: 978-1-56700-471-7
3rd Thermal and Fluids Engineering Conference (TFEC)
AN ANALYTICAL MODEL FOR HEAT AND MASS TRANSFER PROCESSES IN NEW HYBRID INDIRECT/DIRECT EVAPORATIVE COOLER CONCEPT WITH PARALLEL FLOW CONFIGURATION
Abstract
Evaporative coolers utilize the evaporation of water to cool air. The advantage is to use only a fraction of the
energy of typical compressor-based cooling systems. The objective of the current investigation is to introduce
an effective small system dealing only with primary flow in which the indirect and direct processes exist in
the same channel. This innovative system provides an appropriate alternative to mechanical vapor compression
systems for dry climate regions. The importance of such a system is not limited to energy saving and
environmental safety but can also effectively handle the bacteria source, maintenance, and cleaning. Moreover,
eliminating the dependency on a secondary flow will either increase the air supply flow rate by increasing
primary air flow channels or reducing the evaporation size. An analytical model is developed for the coupled
heat and mass transfer processes in a hybrid (indirect and direct) evaporative cooler. The model considers the
flow and channel wall temperature, which fluctuates in the indirect (dry) section and in the direct (wet) section.
Diffusion mass transfer of water vapor and relative humidity variation within the channel are considered and
combined with convection heat transfer equations to predict the flow effect. However, the effects of changing
the operation conditions and channel wall thickness were taken into account during the prediction of the
system's performance. Comparative results show that the hybrid concept has a great potential in the future of
evaporative cooler system.