In this work, a two-phase mixture approach is utilized to examine the influence of nanoadditive shape on the fluid flow and heat transfer aspects of gamma-AlOOH nano-fluid flowing through a sinusoidal wavy channel. The gamma-AlOOH (boehmite alumina) nanoadditives of various shapes (i.e. cylindrical, brick, blade, and platelet) are dispersed in 50/50 water-ethylene glycol mixture as the base fluid. The influence of the Reynolds number and nanoadditive volume fraction on the Nusselt number, pressure drop, and performance evaluation criterion (PEC) are numerically studied for different nanoadditive shapes. It is revealed that, among the considered nanoadditive shapes, the platelet shape represents the highest heat transfer performance, while the worst performance belongs to the brick shape nanoadditives. In addition, the findings reveal that for all states, enhancing the Reynolds number intensifies the Nusselt number, pressure drop, and PEC of the gamma-AIOOH nano-fluid. Moreover, it is found that boosting the nanoadditive fraction leads to an enhancement in the Nusselt number and PEC of the examined nano-fluids. Furthermore, the pressure drop of all the considered nano-fluids enhances with augmenting the Reynolds number. (C) 2019 Elsevier B.V. All rights reserved.