Exergy is defined as the maximum amount of work that
can be produced by a system or a flow of matter or energy
to reach equilibrium with a reference environment. Energy
and exergy analyses of the drying process should be
performed to determine the energy interactions and thermodynamic
behavior of drying air throughout a drying
chamber. Exergy analysis allows for a more efficient energy
resource use because the analysis enables the determination
of the locations, types, and true magnitudes of the losses.
Therefore, exergy analyses can reveal where and by how
much designing more efficient thermal systems is possible
by reducing the sources of existing inefficiencies. Increased
efficiency can often contribute in an making these processes
environmentally friendly by directly reducing the
irreversibilities (where exergy is destroyed) that might
otherwise occur. Therefore, exergy is one of the most
powerful tools in providing optimum drying conditions.
In the past few decades, thermodynamic analysis, particularly
exergy analysis, has become an essential tool in the
system design, analysis, and optimization of a thermal
system (Chowdhury et al., 2011). The energy analysis
method is widely used in evaluating the performance of
the food drying system, but studies on exergy analysis
remain relatively limited.
Several studies were conducted on the exergy analyses of
food drying. Midili and Kucuk (2003) performed energysystem for red chili. Therefore, the main objective of this
study is to perform energy and exergy analyses of the solar
drying system for red chili and exergy analyses of the drying process of shelled and
unshelled pistachios by using a solar drying cabinet.
Akpinar (2004) performed energy and exergy analyses in
drying red pepper slices by using a convective type dryer.
Dincer and Sahin (2004) developed a new model for the
thermodynamic analysis of the drying process. Akpinar
et al. (2006) conducted first and second law analyses of
the thermodynamics of the pumpkin drying process. Colak
and Hepbasli (2007) performed exergy analysis on the thin
layer of a green olive in a tray dryer. Corzo et al. (2008)
performed energy and exergy analyses of the thin layer
drying of coroba slices at three different air temperatures.
Ozgener and Ozgener (2009) examined the exergy variation
during the drying process in a passively heated solar
greenhouse. Akpinar (2010) performed energy and exergy
analyses of the solar drying process of mint leaves. Exergy
efficiencies were derived as a function of the drying time
and temperature of the drying air. Akpinar (2011) reported
on the energy and exergy analyses of the solar drying of
parsley leaves and the variations of the exergy inflow,
outflow, and loss with the drying time. Chowdhury et al.
(2011) also reported that exergy inflow, outflow, and
exergy loss follow similar pattern. The variations in the
exergy inflow, outflow, and loss in solar drying are caused
by variations in daily solar radiation. However, no study
has reported on the exergy analysis of the solar drying