Performance Analysis of Squid-like Underwater Propulsion System

To address the issues of high energy consumption, low hydrodynamic efficiency, and high noise associated with conventional underwater propulsion systems, we propose a bionic squid underwater propulsor. This propulsor is based on a deployable waterbomb origami mechanism that emulates mantle contraction. It features a well-distributed architecture and achieves nearly ۱۰۰% radial shrinkage. Utilizing this biomimetic principle, we established a simplified origami-mantle model. With prescribed elastomer deformation and a periodic jet-velocity profile, we employed a physics-based thrust-drag decoupling method to numerically investigate the propulsion performance and efficiency under varying background flow conditions. Our results indicate distinct trends in jet momentum flux, exit-plane normal stress, and internal flow acceleration with varying inflow velocity and nozzle diameter. As the background flow increases, inflow resistance rises, and net thrust gradually decreases, whereas propulsion efficiency continues to increase. Specifically, when the background flow is between ۰.۴Vjm-۰.۶۲Vjm, the cycle-averaged efficiency ranges from ۱۰% to ۳۰%. For different nozzle sizes, larger nozzles deliver both stronger thrust output and higher energy utilization efficiency, highlighting the critical role of nozzle sizing in performance optimization. To further demonstrate feasibility, tank experiments on the prototype achieved an average swimming speed of ۷.۶۴ cm/s (۰.۳۲ BL/s), a peak speed of ۱۲.۶ cm/s (۰.۵۳ BL/s), and a thrust of ۰.۳ N.

کلیدواژه ها:

Underwater propulsion system ، Bionic squid ، Waterbomb origami mechanism ، Thrust-drag decoupling method ، Numerically study