SYMBOL

DESCRIPTION

VALUE

units

$C_{P,HTF}$

Specific heat, heat transfer fluid

4.186

J/(g・˚C)

$C_{P,WF}$

Specific heat, working fluid

1.330

J/(g・˚C)

DNI_min

Minimum radiation for system start-up

350

W/m²

Lat

Latitude

30˚13'27''N

$D_5$

Outside diameter of HCE glass envelope

0.125

m

${\epsilon }_5$

Emissivity of outer surface of glass envelope

0.093

${\alpha }_{ABS}$

Absorptivity of HCE selective coating

0.955

${\eta }_{ENV}$

Effective optical efficiency of HCE envelope

0.67

${\alpha }_{ENV}$

Absorptivity of HCE glass envelope

0.20

A

Reflective area of one SCA

525

m²

L

Length of one HCE receiver section

6

m

$T_{5,ST}$

Glass envelope outer surface initial temperature

96.3

C

$K_{56}$

Thermal conductance of air at T_5-6

0.6969

W/(m・K)

${\alpha }_{56}$

Thermal diffusivity of air at T_5-6

0.00002207

m²/s

${\nu }_{56,ST}$

Kinematic viscosity of air at T_5-6

0.000001568

m²/s

$T_5$

Initial HTF temperature entering solar panel

28

˚C

$T_4$

Initial WF temperature entering boiler

18

˚C

$T_9$

Initial cooling water temperature entering condenser

23.11

˚C

${\eta }_B$

Thermal efficiency of boiler

0.85

${\eta }_{turb}$

Thermal efficiency of turbine/expander

0.75

${\eta }_{cond}$

Thermal efficiency of condenser

0.60

${\eta }_{pump}$

Isentropic efficiency of pump

0.60

${\eta }_{gen}$

Electric efficiency of generator

0.91

${\eta }_{CT}$

Thermal efficiency of cooling tower

0.75

$\dot{m}$

Mass flow rate of condensing loop

12.6

kg/s

$\dot{m}$

Mass flow rate of HTF

6.14

kg/s

$\dot{m}$

Initial mass flow rate of WF

0.859

kg/s

$P_{low}$

Low pressure point of WF

0.142

MPa

$P_{high}$

High pressure point of WF

0.716

MPa

$\sigma$

Stefan-Boltzmann constant

5.67037 × 10⁻⁰⁸

W/(m²・K⁴)