# Research on the Postural Stability of Underwater Bottom Platforms with Different Burial Depths

## TL;DR

This paper studies how different burial depths affect the stability of underwater bottom platforms under ocean currents.

## Contribution

A novel fluid-structural simulation model is proposed to analyze the postural stability of underwater bottom platforms at various burial depths.

## Key findings

- Platforms buried deeper than 0.6 m show a deflection angle less than 5° under 3 kn ocean currents.
- Burial depth significantly influences the maximum displacement and postural stability of the platform.
- The study provides a method to evaluate and ensure the stability of underwater sensors in ocean engineering.

## Abstract

The bottom platform is an important underwater sensor that can be used in communications, early warning, monitoring, and other fields. It may be affected by earthquakes, winds, waves, and other loads in the working environment, causing changes in posture and affecting its sensing function. Therefore, it is of practical engineering significance to analyze the force conditions and posture changes in the bottom platform. In order to solve the problem of postural stability of the underwater bottom platform, this paper establishes a fluid and structural simulation model of the underwater bottom platform. First, computational fluid dynamics (CFD) technology is used to solve the velocity distribution and forces in the watershed around the bottom platform under a 3 kn ocean current, where the finite element method (FEM) numerical calculation method is used to solve the initial equilibrium state of the bottom platform after it is buried. On this basis, this paper calculates the forces on the bottom platform and the posture of the bottom platform at different burial depths under the action of ocean currents. Additionally, the effects of different burial depths on the maximum displacement, deflection angle, and postural stability of the bottom platform are studied. The calculation results show that when the burial depth is greater than 0.6 m, and the deflection angle of the bottom platform under the action of the 3 kn sea current is less than 5°, the bottom platform can maintain a stable posture. This paper could be used to characterize the postural stability of underwater bottom platforms at different burial depths for the application of underwater sensors in ocean engineering.