modelAbsorberSchott_24_01_2014
Information
It solves the 1D radial energy balance around the Heat Collector Element of a solar collector based on the Schott test analysis
(see NREL Heat loss Testing of Schott's 2008 PTR70 Parabolic Trough Receiver )
Parameters
| Type | Name | Default | Description |
|---|
| Boolean | PTR | | Set true to use the 2008 PTR collector |
| Real | pi | Modelica.Constants.pi | |
| Real | Sigma | Modelica.Constants.sigma | Stefan-Boltzmann constant |
| Real | gg | Modelica.Constants.g_n | Standard acceleration of gravity on earth |
| Real | Alpha_t | if PTR then 0.97 else 0.96 | Tube Absorptivity |
| Integer | N | 2 | number of cells |
| Integer | Nt | 1 | number of tubes |
| Modelica.SIunits.Length | L | | length of tubes |
| Modelica.SIunits.Length | ll | L/(N - 1) | Length of each cell |
| Modelica.SIunits.Length | A_P | | Aperture of the parabola |
| General › Optical Properties |
| Real | eps1 | | HCE Shadowing |
| Real | eps2 | | Tracking error |
| Real | eps3 | | Geometry error |
| Real | rho_cl | | Mirror reflectivity |
| Real | eps4 | | Dirt on Mirrors |
| Real | eps5 | | Dirt on HCE |
| Real | eps6 | | Unaccounted |
| General › Thermal energy loss correlation coefficients |
| Real | A0 | 4.05 | |
| Real | A1 | 0.247 | |
| Real | A2 | -0.00146 | |
| Real | A3 | 5.65E-6 | |
| Real | A4 | 7.62E-8 | |
| Real | A5 | -1.7 | |
| Real | A6 | 0.0125 | |
| General › GeometriesAndProperties of the glass envelope |
| Modelica.SIunits.Length | Dext_t | | External diameter tube |
| Modelica.SIunits.Length | th_t | | tube thickness |
| Modelica.SIunits.Length | rext_t | Dext_t/2 | External Radius Glass |
| Modelica.SIunits.Length | rint_t | rext_t - th_t | Internal Radius Glass |
Components
| Type | Name | Default | Description |
|---|
| Modelica.SIunits.Area | A_ext_t | | Lateral external area of the tube |
| Modelica.SIunits.Area | Am_t | | Area of the metal cross section |
| Modelica.SIunits.Area | A_ref | | Area of the reflector |
| Modelica.SIunits.Area | A_int_t | | Total Internal area |
| Modelica.SIunits.Area | A_int_t_l | | Internal area of a cell |
| Modelica.SIunits.Temperature[N] | T_fluid | | temperature of the fluid |
| Modelica.SIunits.HeatFlowRate | Q_tube_tot | | |
| Real[N] | HL | | Heat losses per meter |
| Modelica.SIunits.HeatFlux[N] | Phi_tube_tot | | Heat flux to the tube |
| Modelica.SIunits.HeatFlux[N] | Phi_conv_f | | Heat flux to the fluid |
| Modelica.SIunits.HeatFlux[N] | Phi_loss_tube | | Heat flux loss per tube surface |
| Modelica.SIunits.HeatFlux[N] | Phi_loss_ref | | Heat flux loss per reflector surface |
| Modelica.SIunits.HeatFlux | Phi_loss_ref_m | | Medium heat flux loss per reflector surface |
| Real | eta_opt | | |
| Real | eta_opt_t | | |
| Real | IAM | | Incident Angle Modifier |
| Real[N] | eta_th | | Thermal efficiency at each node |
| Real[N] | eta_TOT | | Total efficiency : eta_th * eta_opt_t |
| Real | Eta_th | | Average thermal efficiency |
| Real | Eta_TOT | | Total Average efficiency |
