IEA Solar Heating and Cooling Programm - NachhaltigWirtschaften.at

IEA SHC Task 38 Solar Air Conditioning and Refrigeration Subtask C2-A, November 9, 2009
NTU number of transfer unit [-]
S area [m 2 ]
t time [s]
T a
T eq
T i
T m
air temperature [K]
equilibrium temperature [K]
air temperature in the section i (i=1;9) [K]
matrix temperature [K]
u fluid velocity (m.s -1 )
V volume (m 3 )
w a
W d
humidity ratio of moist air. [Kg.Kg -1 dryair]
water content of desiccant [Kg.Kg -1 desiccant]
x variable [arbitrary]
z coordinate in the fluid flow direction [m]
Greek letters
ε emissivity [dimensionless]
γ i parameter used in the reduction of desiccant wheel equations [-]
∆λ parameter in the desiccant enthalpy [-]
µ ratio of matrix mass over air mass [-]
η cf efficiency of the counter flow heat exchanger [-]
τα transmission-absorptance coefficient
σ Stefan Boltzmann constant [W.K -4 m -2 ]
ρ density [kg.m -3 ]
λ conductivity [W.K -1 m -1 ]
τ ro
half period of rotation of the desiccant wheel [s]
θ cylindrical coordinate or angular position [rd]
Subscripts
a air
b buffer
c condenser
d desiccant
eq equilibrium
f fluid
g glass
i inlet
H heat pipe
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