Nanostructure-dependent nanobubble drag reduction on NiTi self-adaption surface

Abstract

Under the inspiration of visualized nanobubbles associated with rugged interface, molecular simulations are performed to study thermally induced phase transition in NiTi shape-memory alloys. The perfect reversibility between the cubic austenite B2 and monoclinic martensitic B19′ phases showed two types of morphological structures in the nanoscale. The nanostructures were established as the wall of the nanochannel, which was used to predict the nanobubble flow behavior in the ternary system. Results indicated that the interface with low-temperature B19′ exhibited attractiveness to trap the nanobubble, resulting in low drag coefficient. Conversely, the interface with high-temperature B2 repulsed the nanobubbles as the bulk one, resulting in high drag coefficient. This study provides foresight to invest in shape memories for nanostructure temperature response, which helps realize nanobubble drag reduction.