In this research work, a numerical simulation is carried out to study the performance of coupled mixing and heating generated by chaotic advection in a mixer comprising rotating rods uphold inside a cylindrical tank. The effect of the number of the rotating rods on both the chaotic advection and the thermal efficiency of the mixer is presented. It is found that the use of noncontinuous wall rotations is necessary to ameliorate the heat transfer by chaotic mixing. The increase in the number of rod within the mixer can also promote the thermal performance of the mixer.