Continuous heat removal from the fuel channels in the calendria based reactor is important to avoid any hazardous aftermath. The primary objective of present study is to analyze heat removal capacity of calendria for four different fuel channel configuration. As a design optimization point of view there will be many design parameters need to optimize, in the former analysis, it was observed that the mass flow rate and inlet orientation have a significant effect on the convective heat transfer from the fuel channels to the moderator. The combination of mass flow rate and the inlet angle leading to lowest maximum temperatures inside the calendria was found to cause the underutilization of the calendria. Hence the latter part of the analysis has been carried out in the direction of improving the efficiency of the calendria by splitting the mass of flow near the inlet. In the present paper, the discussion has been done on heat removal capacity of calendria based reactor for inline and staggered fuel channel configurations. The numerical study shows that square pitch 900 inline arry configuration is better as compared to other considered configurations. © ICCFD 2018.