The two-dimensional model for peak conditions is modelled with a fine mesh, with 5.0mm edge mesh sizing on
the mirrors, about 1.0mm on the collector pipes and 20.0mm cell sizing throughout the rest of the model. This
resulted in a mesh with about 900 000 cells, the exact number depending on the detail of each mirror field. This
mesh size was obtained after a sensitivity study comparing total absorbed radiation by varying both mesh size and
the angular discretization settings of the Discrete Ordinates radiation model. The latter includes the two solid angle
increments and the pixilation using in ANSYS Fluent. Angular increments of 20 with 10 pixels each were found to be
sufficient for comparison purposes. This meant that, in addition to the energy equation, a further 4x20x20 = 1600
differential equations were solved in the discrete ordinates implementation of the Radiation Transport Equation, as
each quadrant in two-dimensions is subdivided.