Millifluidics, microfluidics, and nanofluidics: manipulating fluids at varying length scales

Manipulating fluids at varying length scales and understanding their underlying mechanisms are significant for interdisciplinary studies of physics, chemistry, biology, and engineering; fluid manipulation plays an important role in both scientific research and industrial applications. Here, we systematically review millifluidics, microfluidics, and nanofluidics with dimensions ranging from millimeters to nanometers. The major physics associated with flow property and interactions of millifluidics, microfluidics, and nanofluidics are discussed in detail, especially the differences arising from different length scales. Device fabrication techniques are summarized including additive and nonadditive manufacturing methods for millifluidics and microfluidics and top-down and bottom-up strategies for nanofluidics. Recent developments and applications of millifluidics, microfluidics, and nanofluidics are described to provide an overview on current researches. Outlooks of millifluidics, microfluidics, and nanofluidics are discussed at the end.