Experimental and numerical analysis of hovering multicopter performance in low-Reynolds number conditions

Ruiz, Manuel Carreño; Scanavino, Matteo; D’Ambrosio, Domenic; Guglieri, Giorgio; Vilardi, Andrea

doi:10.1016/j.ast.2022.107777

Cited by 11 publications

(4 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The rotational motion of the rotors is modeled with a dynamic mesh approach in which a portion of the grid embedding the rotor slides inside an outer static grid using an arbitrary nesh interface (AMI) protocol. This approach has been validated in [32][33][34]. The generated mesh consists of 10 million cells.…”

Section: Methodsmentioning

confidence: 99%

Numerical Analysis and Wind Tunnel Validation of Droplet Distribution in the Wake of an Unmanned Aerial Spraying System in Forward Flight

Ruiz

Bloise

Guglieri

et al. 2022

Drones

Self Cite

View full text Add to dashboard Cite

Recent developments in agriculture mechanization have generated significant challenges towards sustainable approaches to reduce the environmental footprint and improve food quality. This paper highlights the benefits of using unmanned aerial systems (UASs) for precision spraying applications of pesticides, reducing the environmental risk and waste caused by spray drift. Several unmanned aerial spraying system (UASS) operation parameters and spray system designs are examined to define adequate configurations for specific treatments. A hexarotor DJI Matrice 600 equipped with T-Motor 15“×5” carbon fiber blades is tested numerically using computational fluid dynamics (CFD) and experimentally in a wind tunnel. These tests assess the aerodynamic interaction between the wake of an advancing multicopter and the fine droplets generated by atomizers traditionally used in agricultural applications. The aim of this research is twofold. First, we analyze the effects of parameters such as flight speed (0, 2, and 3 m.s−1), nozzle type (hollowcone and fan), and injection pressure (2–3 bar) on spray distribution. In the second phase, we use data from the experimental campaign to validate numerical tools for the simulation of rotor–droplet interactions necessary to predict spray’s ground footprint and to plan a precise guidance algorithm to achieve on-target deposition and reduce the well-known droplet drift problem.

show abstract

Section: Methodsmentioning

confidence: 99%

Numerical Analysis and Wind Tunnel Validation of Droplet Distribution in the Wake of an Unmanned Aerial Spraying System in Forward Flight

Ruiz

Bloise

Guglieri

et al. 2022

Drones

Self Cite

View full text Add to dashboard Cite

show abstract

“…Some of the NASA reference vehicles have designs more like conventional rotorcrafts, but many of them are more similar to the rotor configurations discussed in this work. New studies delving further into the analysis of these vehicles range topics covering comprehensive and CFD analyses, handling qualities, system design, hazard analysis, and wind-tunnel testing [36][37][38][39][40][41][42][43][44][45][46][47]. Of particular interest to this work are recent studies of mid-air deployment and high rates of descent with these vehicles [48][49][50][51][52].…”

Section: Introductionmentioning

confidence: 99%

Rotor Performance Predictions for Urban Air Mobility: Single vs. Coaxial Rigid Rotors

Cornelius,

Schmitz,

Palacios

et al. 2024

Aerospace

View full text Add to dashboard Cite

This work details the development and validation of a methodology for high-resolution rotor models used in hybrid Blade Element Momentum Theory Unsteady Reynolds Averaged Navier–Stokes (BEMT-URANS) CFD. The methodology is shown to accurately predict single and coaxial rotor performance in a fraction of the time required by conventional CFD methods. The methodology has three key features: (1) a high-resolution BEMT rotor model enabling large reductions in grid size, (2) a discretized set of momentum sources to interface between the BEMT rotor model and the structured URANS flow solver, and (3) leveraging of the first two features to enable highly parallelized GPU-accelerated multirotor CFD simulations. The hybrid approach retains high-fidelity rotor inflow, wake propagation, and rotor–rotor interactional effects at a several orders of magnitude lower computational cost compared to conventional blade-resolved CFD while retaining high accuracy on steady rotor performance metrics. Rotor performance predictions of thrust and torque for both single and coaxial rotor configurations are compared to test the data that the authors obtained at the NASA Langley 14- by 22-ft. Subsonic Tunnel Facility. Simulations were run with both fully turbulent and free-transition airfoil performance tables to quantify the associated uncertainty. Single rotor thrust and torque were predicted on average within 4%. Coaxial thrust and power were predicted within an average of 5%. A vortex ring state (VRS) shielding phenomenon for coaxial rotor systems is also presented and discussed. The results support that this hybrid BEMT-URANS CFD methodology can be highly parallelized on GPU machines to obtain accurate rotor performance predictions across the full spectrum of possible UAM flight conditions in a fraction of the time required by conventional higher-fidelity methods. This strategy can be used to rapidly create look-up tables with hundreds to thousands of flight conditions using a three-dimensional multirotor CFD for UAM.

show abstract

“…Unsteady Reynolds-averaged Navier-Stokes (URANS) simulation is employed to investigate the unsteady flows around a quadcopter in this study. The URANS approach has been successfully used in previous studies such as large-scale rotorcraft [3,4,15,14,16,17] and small-scale multicopters [18,19,20,21]. The overset mesh method in the flow solver OpenFOAM [22,23,24,25] is explored for the simulation of a quadcopter here.…”

Section: Introductionmentioning

confidence: 99%

Numerical study on interactional aerodynamics of a quadcopter in hover with overset mesh in OpenFOAM

Park,

Jee

2023

Physics of Fluids

View full text Add to dashboard Cite

Interactional aerodynamics of a quadcopter in hover is numerically investigated in this study. The main objective is to understand major flow structures associated with unsteady airloads on multirotor aircraft. The overset mesh approach is used to resolve flow structures in unsteady simulation using the flow solver OpenFOAM. The current computational study demonstrates that aerodynamic interaction between quadcopter components strongly affects the rotor wake, generating interesting vortical structures. Multiple rotors in close proximity generate Ω-shaped vortical structures merged from rotor-tip vortices. The fuselage of the current quadcopter deflects the wake flow of the four rotors toward the center of the vehicle. Such interactional aerodynamics, i.e., rotor–rotor and rotor–fuselage interaction, varies the inflow condition of a rotor blade during the rotor revolution. Therefore, the quadcopter experiences unsteady airloads per rotor revolution. Our study indicates that a typical quadcopter would experience 8/rev thrust variations, which are a combined outcome from 4/rev thrust variations on the rotor and 2/rev fluctuations on the fuselage. The current understanding of interactional aerodynamics could help to design reliable and efficient multicopter aircraft.

show abstract

Experimental and numerical analysis of hovering multicopter performance in low-Reynolds number conditions

Cited by 11 publications

References 11 publications

Numerical Analysis and Wind Tunnel Validation of Droplet Distribution in the Wake of an Unmanned Aerial Spraying System in Forward Flight

Numerical Analysis and Wind Tunnel Validation of Droplet Distribution in the Wake of an Unmanned Aerial Spraying System in Forward Flight

Rotor Performance Predictions for Urban Air Mobility: Single vs. Coaxial Rigid Rotors

Numerical study on interactional aerodynamics of a quadcopter in hover with overset mesh in OpenFOAM

Contact Info

Product

Resources

About