Effects of Atmospheric Uncertainties on Sonic Boom Perceived Level

Abstract This work quantifies the uncertainty in Stevens Mark VII Perceived Level of sonic booms due to uncertainties in atmospheric profiles. The influence of temperature, humidity, and wind profiles, at six cities around the globe, on the sonic boom loudness is calculated. The flow field around an aircraft was obtained by solving the three-dimensional (3D), compressible Euler equations using the UNS3D solver. The near-field pressure signature is then propagated through the atmosphere by solving the augmented Burgers equation using the sBOOM solver. The uncertainty is modeled using a nonintrusive polynomial chaos approach. A sensitivity analysis is performed to identify the altitude range and the atmospheric variable to which the Perceived Level is most sensitive. It was shown that the Perceived Level is not sensitive to any particular altitude but rather the atmospheric profiles. It was also seen that the Perceived Level is highly sensitive to humidity and temperature profiles and less sensitive to the wind profiles.

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Roughness effect on the efficiency of dimer antenna based biosensor

Advanced Electromagnetics ◽

10.7716/aem.v1i2.20 ◽

2012 ◽

Vol 1 (2) ◽

pp. 41 ◽

Cited By ~ 2

Author(s):

D. Barchiesi ◽

S. Kessentini

Keyword(s):

Surface Roughness ◽

Near Field ◽

Three Dimensional ◽

Biological Molecules ◽

Far Field ◽

Dimensional Model ◽

Three Dimensional Model ◽

Roughness Effect ◽

Highly Sensitive ◽

Local Plasmon

The fabrication process of nanodevices is continually improved. However, most of the nanodevices, such as biosensors present rough surfaces with mean roughness of some nanometers even if the deposition rate of material is more controlled. The effect of roughness on performance of biosensors was fully addressed for plane biosensors and gratings, but rarely addressed for biosensors based on Local Plasmon Resonance. The purpose of this paper is to evaluate numerically the influence of nanometric roughness on the efficiency of a dimer nano-biosensor (two levels of roughness are considered). Therefore, we propose a general numerical method, that can be applied to any other nanometric shape, to take into account the roughness in a three dimensional model. The study focuses on both the far-field, which corresponds to the experimental detected data, and the near-field, responsible for exciting and then detecting biological molecules. The results suggest that the biosensor efficiency is highly sensitive to the surface roughness. The roughness can produce important shifts of the extinction efficiency peak and a decrease of its amplitude resulting from changes in the distribution of near-field and absorbed electric field intensities.

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The Wave Formation and Sonic Boom due to a Delta Wing

Aeronautical Quarterly ◽

10.1017/s0001925900005977 ◽

1972 ◽

Vol 23 (2) ◽

pp. 87-108 ◽

Cited By ~ 6

Author(s):

K Oswatitsch ◽

Y C Sun

Keyword(s):

Delta Wing ◽

Near Field ◽

Three Dimensional ◽

Vertical Plane ◽

Wave Formation ◽

Sonic Boom ◽

Body Of Revolution ◽

Trailing Edge ◽

Finite Distance ◽

Wave Signature

SummaryBy employment of the analytical method of characteristics and of a limiting procedure suitable for dealing with the trailing edge expansion, the influence of near-field flow on the far-field wave formation has been investigated for an incident flat delta wing with supersonic leading edges. Though confined in its scope to the front shock in the vertical plane of symmetry of the wing and to a homogeneous atmosphere without density and temperature gradients, the present analysis reveals features of flow which are interesting from the standpoint of the general theory of three-dimensional supersonic flow. It is found that the front shock due to a delta wing will as a rule be cancelled at a finite distance from the wing by the plane-wave expansion emanating from the trailing edge. The over-expansion must then give rise to a rear shock separate from the front one. Thus, at least in the plane of symmetry, a sharp-front wave signature can not, in general, be expected from the wing at a distance beyond the terminating point of the front shock. The boom signature then will be qualitatively different from that of a body of revolution. The general non-equivalence of a wing to a body of revolution in this respect should evoke some rethinking about sonic boom prediction and alleviation.

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DLR TAU Simulations for the Third AIAA Sonic Boom Prediction Workshop Near-Field Cases

AIAA Scitech 2021 Forum ◽

10.2514/6.2021-0472 ◽

2021 ◽

Author(s):

Jochen Kirz

Keyword(s):

Near Field ◽

Sonic Boom ◽

The Third

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A Three-Dimensional Tetraphenylethylene-Based Fluorescence Covalent Organic Framework for Molecular Recognition

10.26434/chemrxiv.12982019 ◽

2020 ◽

Author(s):

Junxia Ren ◽

Yaozu Liu ◽

Xin Zhu ◽

Yangyang Pan ◽

Yujie Wang ◽

...

Keyword(s):

Molecular Recognition ◽

Fluorescence Probe ◽

Three Dimensional ◽

Hazardous Substances ◽

Covalent Organic Framework ◽

Highly Sensitive ◽

Volatile Organic ◽

Polycyclic Aromatic ◽

Better Than ◽

Organic Framework

<a></a><a></a><a></a><a></a><a></a><a></a><a></a><a>The development of highly-sensitive recognition of </a><a></a><a></a><a></a><a></a><a>hazardous </a>chemicals, such as volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs), is of significant importance because of their widespread social concerns related to environment and human health. Here, we report a three-dimensional (3D) covalent organic framework (COF, termed JUC-555) bearing tetraphenylethylene (TPE) side chains as an aggregation-induced emission (AIE) fluorescence probe for sensitive molecular recognition.<a></a><a> </a>Due to the rotational restriction of TPE rotors in highly interpenetrated framework after inclusion of dimethylformamide (DMF), JUC-555 shows impressive AIE-based strong fluorescence. Meanwhile, owing to the large pore size (11.4 Å) and suitable intermolecular distance of aligned TPE (7.2 Å) in JUC-555, the obtained material demonstrates an excellent performance in the molecular recognition of hazardous chemicals, e.g., nitroaromatic explosives, PAHs, and even thiophene compounds, via a fluorescent quenching mechanism. The quenching constant (KSV) is two orders of magnitude better than those of other fluorescence-based porous materials reported to date. This research thus opens 3D functionalized COFs as a promising identification tool for environmentally hazardous substances.

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From near-field to far-field: Radiative coupling of particle plasmon resonances in three-dimensional geometries

2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC) ◽

10.1109/cleoe.2011.5943224 ◽

2011 ◽

Author(s):

Richard Taubert ◽

Ralf Ameling ◽

Thomas Weiss ◽

Andre Christ ◽

Harald Giessen

Keyword(s):

Near Field ◽

Three Dimensional ◽

Far Field ◽

Radiative Coupling ◽

Plasmon Resonances ◽

Particle Plasmon

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Thermomechanical Coupling of a Hyper-viscoelastic Truck Tire and a Pavement Layer and its Impact on Three-dimensional Contact Stresses

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/03611981211017140 ◽

2021 ◽

pp. 036119812110171

Author(s):

Angeli Jayme ◽

Imad L. Al-Qadi

Keyword(s):

Contact Stress ◽

Contact Area ◽

Three Dimensional ◽

Interaction Model ◽

Rolling Resistance ◽

Contact Stresses ◽

Thermomechanical Coupling ◽

Temperature Profiles ◽

Near Surface ◽

Truck Tire

A thermomechanical coupling between a hyper-viscoelastic tire and a representative pavement layer was conducted to assess the effect of various temperature profiles on the mechanical behavior of a rolling truck tire. The two deformable bodies, namely the tire and pavement layer, were subjected to steady-state-uniform and non-uniform temperature profiles to identify the significance of considering temperature as a variable in contact-stress prediction. A myriad of ambient, internal air, and pavement-surface conditions were simulated, along with combinations of applied tire load, tire-inflation pressure, and traveling speed. Analogous to winter, the low temperature profiles induced a smaller tire-pavement contact area that resulted in stress localization. On the other hand, under high temperature conditions during the summer, higher tire deformation resulted in lower contact-stress magnitudes owing to an increase in the tire-pavement contact area. In both conditions, vertical and longitudinal contact stresses are impacted, while transverse contact stresses are relatively less affected. This behavior, however, may change under a non-free-rolling condition, such as braking, accelerating, and cornering. By incorporating temperature into the tire-pavement interaction model, changes in the magnitude and distribution of the three-dimensional contact stresses were manifested. This would have a direct implication on the rolling resistance and near-surface behavior of flexible pavements.

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Imaging of bi-anisotropic periodic structures from electromagnetic near-field data

Journal of Inverse and Ill-Posed Problems ◽

10.1515/jiip-2020-0114 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Dinh-Liem Nguyen ◽

Trung Truong

Keyword(s):

Inverse Scattering ◽

Maxwell Equations ◽

Field Data ◽

Periodic Structures ◽

Near Field ◽

Scattering Problem ◽

Three Dimensional ◽

Inverse Scattering Problem ◽

Factorization Method ◽

Unique Determination

AbstractThis paper is concerned with the inverse scattering problem for the three-dimensional Maxwell equations in bi-anisotropic periodic structures. The inverse scattering problem aims to determine the shape of bi-anisotropic periodic scatterers from electromagnetic near-field data at a fixed frequency. The factorization method is studied as an analytical and numerical tool for solving the inverse problem. We provide a rigorous justification of the factorization method which results in the unique determination and a fast imaging algorithm for the periodic scatterer. Numerical examples for imaging three-dimensional periodic structures are presented to examine the efficiency of the method.

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