EXPERIMENTAL AND NUMERICAL INVESTIGATIONS OF SOLAR FLUX DENSITY DISTRIBUTION OVER FLAT PLATE RECEIVER OF MODEL HELIOSTAT SYSTEM

The flux density distribution and the temperature of the receiver are important parameters to assess the net thermal energy of any Solar Power Concentrator. In the present work, a heliostat field utilizing ganged type of heliostats for process heating application has been designed. A prototype model of the central receiver system consisting of ganged heliostats has been constructed and installed at Pune, Maharashtra, India. A thermocouple method was used to evaluate the total energy focused by the model heliostat system on a flat receiver. The flux density distribution was validated with the ray tracing simulation software ‘SolTrace’. The simulated flux density distribution was found to be in agreement with the measured one for a surface normal error of 10 milliradian. A heliostat field having 100 m2 total mirror area was designed in the north south cornfield layout. This heliostat field was simulated in ‘SolTrace’ software by considering the surface normal errors as 10 milliradian and the total energy gain was estimated. For the purpose of simulation to investigate the solar flux falling on the receiver, four days of the year were selected. It includes the March equinox, summer solstice, September equinox, and winter solstice.