Page 12 - مشروع تخرج 1

Nomenclatures

̇
Q Q Heat rate, W
-1
m ̇ mass flow rate, kg s
-1
-1
Cp Specific heat capacity under constant pressure, J kg K
T Temperature, C
2
A Area, m
-2
Gb Solar direct beam irradiation, Wm
-2
-1
H Heat transfer of the flow,Wm K
-1
V Wind speed, m s
D Diameter, m
floss Losses factor

Nsc Number of PTC
h Specific enthalpy, kj.kg -1
GOR Gain output ratio
Greek symbols
ΔT Temperature deference C
ϵ Emittance
σ Stefan-Boltzmann constant W · m -2 · K -4

Collector thermal efficiency
Subscripts and superscripts
a aperture
am ambient
b beam
r receiver

ri inner receiver
ro receiver outer
s solar
u useful
c cover
ci cover inner
co outer cover

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