Table 2.

General characteristics of the DAPTC³⁰.

Parameter	Value	Unit	Symbol
Optical properties
Glass tube emittance	–	0.86	${\mathrm{\epsilon }}_{\mathrm{t}}$
Glass tube absorbance	–	0.02	${\alpha }_{\mathrm{t}}$
Glass tube transmittance	–	0.95	${\mathrm{\tau }}_{\mathrm{t}}$
Tracking and other errors	–	0.9	$\mathrm{\gamma }$
Mirror reflectance	–	0.93	rm
Glass cover emittance	–	0.86	${\mathrm{\epsilon }}_{\mathrm{c}}$
Glass cover absorbance	–	0.02	${\alpha }_{\mathrm{c}}$
Glass cover transmittance	–	0.95	${\mathrm{\tau }}_{\mathrm{c}}$
Geometrical properties
Width	m	0.7	G
Length	m	1.5	L
Focal length	m	0.175	F
Glass tube outer diameter	m	0.026	Dt-o
Glass tube inner diameter	m	0.022	Dt-in
Glass cover outer diameter	m	0.06	Dc-o
Glass cover inner diameter	m	0.05	Dc-in
Operating conditions
Nanofluid inlet temperature	${}^{\circ }\mathrm{C}$	30	Tin
Air temperature	${}^{\circ }\mathrm{C}$	26	Ta
Nanofluid flow rate	LPH	60	$\dot{\mathrm{V}}$
Solar irradiance	$\frac{\mathrm{W}}{{\mathrm{m}}^2}$	900	I