Recent progress in self-propelled particles

Self-propelled particles are commonly found in a large number of planktonic organisms such as bacteria, fungi, and algae in nature, and researchers have taken a long interest in exploring their swimming mechanisms for more than a century. Especially in the past 20 years, with the development of computational fluid dynamics and flow display technology, as well as the need for the design of synthetic self-propelled particles and micro-swimming devices, self-propelled particles have become the forefront and hotspot of current research in the field of fluid mechanics. This paper first introduces the swimming characteristics of common self-propelled particles, leading to a classic “squirmer” type self-propelled particle model. On this basis, a systematic introduction and summary of the theoretical and numerical simulation research of “squirmer” will be conducted. Finally, the main challenges and opportunities faced by the current research will be summarized.