This study investigates the heat flux distribution on the absorber (upper and lower) tube and fin of an external compound parabolic collector (XCPC). Two-dimensional radiation simulations were conducted in ANSYS Fluent 2023 R2 using the Discrete Ordinates (DO) method in Finite Volume (FV) to quantify the incident radiation on the pentagon-shaped fin and absorber tube. This method simultaneously solves each iteration’s radiative transport equation (RTE). The 2D DO method is known for its accuracy in identifying scattering effects but it also has limitations, such as false scattering and ray effects which can reduce the accuracy of the results. However, measures have been implemented in literature to address these challenges. The number of cells in the 2D DO simulation ranged from 13 071 to 418 276 to assess the impact of false scattering in the mesh sensitivity analysis for the fin and tube sections. A cell count of 209 138 cells was selected to balance computational cost and time while reducing uncertainty. The angular discretization study investigated different division levels on the 209 138 cells, ranging from coarse (2 × 2) to fine (3 × 200), while keeping a constant 3 × 3 pixelation across all simulations. The results showed that from the 3 × 30 divisions onward, the simulation curves for the tube sections and fin began to overlap. The 3x100 discretization was chosen as it provided reliable results without requiring excessive computational time.