Aerodynamic Investigations of UAV Sensor Turrets - A Combined Wind-tunnel and CFD Approach

Goetten, Falk; Havermann, M.; Braun, Carsten; Marino, Matthew; Bil, Cees

doi:10.2514/6.2021-1535

Cited by 7 publications

(9 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The size of the fluid domain needs to be sufficiently large so that the far field of the fluid surrounding the wing does not interfere with the physical flow phenomena close to the wing. To achieve this, the fluid domain dimensions were defined using the recommendations from [46] to have at least 25 body lengths around a three-dimensional aircraft. The fluid domain consisted of a half-elliptical volume with a semi-major axis of 26 m and a minor axis of 26 m, illustrated in Figure 4.…”

Section: Computational Fluid Dynamics Studies 221 Cfd Geometriesmentioning

confidence: 99%

“…The result is a more efficient mesh that carefully resolves the boundary layers, capturing flow variables more accurately. Emphasis was given to first-cell height at the wall boundaries, with the goal of obtaining y+ values in the order of one to accurately resolve the viscous sub-layer, a practice well discussed by [46,48]. To estimate the first cell height, Equations (1a) to (1d) were used…”

Section: Cfd Meshesmentioning

confidence: 99%

See 1 more Smart Citation

Exploring the Performance Boundaries of a Small Reconfigurable Multi-Mission UAV through Multidisciplinary Analysis

Santos,

Rogers,

De Rezende

et al. 2023

Aerospace

View full text Add to dashboard Cite

The performance of a small reconfigurable unmanned aerial vehicle (UAV) is evaluated, combining a multidisciplinary approach in the computational analysis of additive manufactured structures, fluid dynamics, and experiments. Reconfigurable UAVs promise cost savings and efficiency, without sacrificing performance, while demonstrating versatility to fulfill different mission profiles. The use of computational fluid dynamics (CFD) in UAV design produces higher accuracy aerodynamic data, which is particularly important for complex aircraft concepts such as blended wing bodies. To address challenges relating to anisotropic materials, the Tsai–Wu failure criterion is applied to the structural analysis, using CFD solutions as load inputs. Aerodynamic performance results show the low-speed variant attains an endurance of 1 h, 48 min, whereas its high-speed counterpart is 29 min at a 66.7% higher cruise speed. Each variant serves different aspects of small UAS deployment, with low speed envisioned for high-endurance surveying, and high speed for long-range or time-critical missions such as delivery. The experimental and simulation results suggest room for design iteration, in wing area and geometry adjustments. Structural simulations demonstrated the need for airframe improvements to the low-speed configuration. This paper highlights the potential of reconfigurable UAVs to be useful across multiple industries, advocating for further research and design improvements.

show abstract

Section: Computational Fluid Dynamics Studies 221 Cfd Geometriesmentioning

confidence: 99%

Section: Cfd Meshesmentioning

confidence: 99%

Exploring the Performance Boundaries of a Small Reconfigurable Multi-Mission UAV through Multidisciplinary Analysis

Santos,

Rogers,

De Rezende

et al. 2023

Aerospace

View full text Add to dashboard Cite

show abstract

“…Following the guidelines for external flow simulations given by Goetten et al [60], the trailing edge of the foil is made round and the "airfoil" is forced to be 250 elements for the top and the bottom. Goetten et al further offers guidelines on the extent of the fluid domain.…”

Section: Computational Domainmentioning

confidence: 99%

“…Goetten et al further offers guidelines on the extent of the fluid domain. The group recommends having longitudinal and lateral domain extents greater than 200 reference lengths [60]. Many of the current undulating airfoil simulations do not follow the recommended guidelines for their simulation.…”

Section: Computational Domainmentioning

confidence: 99%

IKA-FLOW : A Flexible Body Overset Mesh Implementation for Fish Swimming

Coe

Gutschmidt

2023

OpenFOAM J

View full text Add to dashboard Cite

Simulation of inertial aquatic swimmers requires fluid structure interactions with temporal body geometry deformation. In practice, his results in a change of the computational domain boundaries that represent the ”swimmer.” These simulations are traditionally done sing body-fitted mesh and mesh morphing methods, but have drawbacks of negative cell volumes and small time-steps to account for the complex swimming motion. In contrast, the overset mesh method, also provided by OpenFOAM®, overcomes most of the drawbacks of the mesh morphing method at the expense of interpolation error. The current OpenFOAM® overset motion library only supports rigid body motion and cannot be used to resolve a body undergoing undulation. A modified motion solver is presented that allows for the complex mesh motion of an overset mesh for four body-caudal fin (BCF) virtual swimmers. The results of this solver are compared with published data of body-fitted meshes. The effect of different simulation parameters (including number of solving iterations, time delay, and temporal resolution) is investigated. Additionally, a novel simulation and comparison of the Ostraciiform locomotion mode with Anguilliform, Carangiform, and Thunniform modes are made investigating the wake, drag and lift. It is concluded that fish undulation has a marked effect on reducing lift generation. Lastly, a comparison of turbulence models (Spalart-Allmaras, k − ω SST, and k − kL − ω) at multiple Reynolds numbers shows that all three models have similar performance at lower Reynolds numbers but diverge at higher numbers.

show abstract

“…Good quality wind tunnels can produce values as low as 0.05%. For this case, scenario I = 0.1% was selected to initialize the simulation [59]. The eddy viscosity ratio for external flows should be in the range of 0.2-1.3, and the value of µ t /µ = 1.3 was selected.…”

Section: Flow Characteristics Configurations and Boundary Conditionsmentioning

confidence: 99%

Leading-Edge Vortex Controller (LEVCON) Influence on the Aerodynamic Characteristics of a Modern Fighter Jet

Malicki,

Malecha,

Tomczuk

2023

Energies

View full text Add to dashboard Cite

The purpose of this paper is to assess the influence of a novel type of vortex creation device called the leading-edge vortex controller (LEVCON) on the aerodynamic characteristics of a fighter jet. LEVCON has become a trending term in modern military aircraft in recent years and is a continuation of an existing and widely used aerodynamic solution called the leading-edge root extension (LERX). LEVCON is designed to operate on the same principles as LERX, but its aim is to generate lift-augmenting vortices, i.e., vortex lift, at higher angles of attack than LERX. To demonstrate the methodology, a custom delta wing fighter aircraft is introduced, and details about its aerodynamic configuration are provided. The LEVCON geometry is designed and then incorporated into an existing three-dimensional (3D) model of the aircraft in question. The research is conducted using OpenFOAM 8, a high-fidelity computational fluid dynamics (CFD) open-source software. The computational cases are designed to simulate the aircraft’s flight at stall velocities within a high range of angles of attack. The results are assessed and discussed in terms of aerodynamic characteristics. A conclusion is drawn from the analysis regarding the perceived improvements in fighter jet aerodynamics. The analysis reveals that both lift and critical angle of attack can be manipulated positively. With the addition of LEVCON, the average lift gain in the high angle of attack (α) range is between 8.5% and 10%, while the peak gain reaches 19.4%. The critical angle of attack has also increased by 2°, and a flatter stall characteristic has been achieved.

show abstract

Aerodynamic Investigations of UAV Sensor Turrets - A Combined Wind-tunnel and CFD Approach

Cited by 7 publications

References 17 publications

Exploring the Performance Boundaries of a Small Reconfigurable Multi-Mission UAV through Multidisciplinary Analysis

Exploring the Performance Boundaries of a Small Reconfigurable Multi-Mission UAV through Multidisciplinary Analysis

IKA-FLOW : A Flexible Body Overset Mesh Implementation for Fish Swimming

Leading-Edge Vortex Controller (LEVCON) Influence on the Aerodynamic Characteristics of a Modern Fighter Jet

Contact Info

Product

Resources

About