FSI Analysis: RQ_11 Drone CFD Simulation Training

Introduction

FSI simulation involves the interaction between the fluid and the structure. If we only want to consider the effects of the fluid on the structure, we use one-way method, and if we want to consider the effect of the structure on the fluid in addition to the effect of the fluid on the structure, we use two-way method. In this simulation, we have performed a two-way simulation. Previously, we could only run the two-way method in Workbench, but now Fluent software also has this capability. However, if our simulation involves large displacements, it is better to use Workbench because Fluent is not able to accurately analyze large displacements.

A lightweight unmanned aircraft system (UAV) with excellent mobility, the RQ_11 Raven Drone, is designed for quick deployment.

The RQ_11 Raven is hand-launched into the air like a model airplane in mere minutes, and it lands itself by auto-piloting to a hovering position. It doesn’t need landing strips that have been adequately prepared. The RQ_11 Raven Drone is best suited for forward-deployed units because it doesn’t require complex support facilities.

Thanks to its automated features and GPS technology, it is easy to use and doesn’t require any specialized knowledge or extensive flight training.

An RQ-11 Raven Drone is modeled in this simulation using ANSYS Fluent software. The device moves at a speed of 13.9  m/s while the propeller rotates at an angular velocity of 1200 rev/min.

The geometry of the present model is three-dimensional and has been designed using SpaceClaim software. We do the meshing of the present model with Ansys Meshing software. The mesh type is Tetrahedral, and the element number is 2,195,749.

Methodology

This study used a steady-state, pressure-based CFD simulation in ANSYS Fluent software to analyze the incompressible flow around a UAV and the fluid-structure interactions. The flow physics was modeled using the k-ω SST turbulence model and a dynamic mesh was also used.

Results and Conclusion

According to the extracted contours, it is observed that, as expected, the greatest displacement occurs at the wing tips of the UAV and the greatest stress is at the wing-body connection.

It is also observed in the graph that the amount of displacement decreases from the wing tips to the body connection and reaches zero at the body. Although the body displacement may sometimes not be zero, its amount is very small and is usually ignored.