To enhance the knowledge of non-uniform heat flux distribution of receiver in a solar power tower plant

an optical simulation software

SolTrace

was used to model the Gemasolar plant system geometrically and optically

and the wall heat flux distribution of the receiver was obtained. According to the convergence judgment

5 000 000 rays were used for follow-up study. The accuracy of the model was verified by comparison with results from the litearture. Under the standard condition at the design point on Summer Solstice

the incident radiation of sunlight was adopted. From the simulation results

it is found that the variation of the solar radiation heat flux received on the wall of different receiver tubes is related to the annular distribution of the heliostat field. For a single absorber

the wall heat flux distribution is non-uniform

and the comparison with the Gaussian approximation distribution proves that this distribution is quite different from the design condition. Then

the heat flux distribution of the receiver at noon of Winter Solstice was obtained by using the model. Overall

it is concluded that SolTrace simulation is more practical than the simplified Gaussian approximation distribution for the treatment of wall heat flux distribution of external cylindrical absorber.