This study analyzed efficiency and heat loss of three types of simple and cut-back receivers. The conjugate simulation was made for situation where the honeycomb receiver receives concentrated radiation heating air stream through square cells. The DO (Discrete Ordinate) approach was adopted to calculate the radiation intensity and to fully couple the flow and three styles of heat transfer. This paper confirmed no significant effects for temperature distribution of the simple channel due to number of grids and angular discretization of DO model. The model is validated by comparing the receiver efficiency between experiments and simulations. After the validation, the simple and two unique geometric (cut-back 1 and 2) channels are investigated changing the air mass flow rate and beam width. There are no great effects from the beam width on the receiver efficiency for three types of different receivers. Whereas, the receiver efficiency was vastly dependent on the air mass flow rate. There are certain value of air mass flow rate maximizing the receiver efficiency. Reducing the air mass flow rate below this criterion resulted in clearly deteriorating the efficiency. The analysis indicated that the re-radiation loss was minimized at a certain level of air mass flow rate maximizing the efficiency for three cases of receivers. (C) 2019 Elsevier Ltd. All rights reserved.