Role of Mie scattering in the seeding of matter-wave superradiance

AbstractThis paper presents the experimental results of the role of struts in supersonic mixing. Experiments were carried out with novel strut configurations to show their capabilities on mixing with reasonable total pressure losses. The performances were compared with the Baseline Strut configurations (BSPI and BSNI). The analysis presented includes the mixing quantifications using Mie scattering signature, flow field visualisation, measurement of wall static pressure and the total pressure loss calculations. The results clearly demonstrated that the proposed strut configurations achieved increased mixing (7-8%) compared to BSPI with increase in total pressure loss (2%). On the other hand, when compared with BSNI, the mixing performance was found to be decreased by 6% with reduced total pressure loss (12%).

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Numerical investigation of the role of hyper-mixers in supersonic mixing

The Aeronautical Journal ◽

10.1017/s0001924000004140 ◽

2010 ◽

Vol 114 (1161) ◽

pp. 659-672 ◽

Cited By ~ 3

Author(s):

S. L. N. Desikan ◽

K. Kumaran ◽

V. Babu

Keyword(s):

High Speed ◽

Static Pressure ◽

Numerical Study ◽

Mie Scattering ◽

Stagnation Pressure ◽

Reacting Flow ◽

Qualitative Comparison ◽

Supersonic Mixing ◽

High Speed Flows

Abstract In this numerical study, the role of hyper-mixers on supersonic mixing is investigated for six different strut configurations. To this end, 3D, compressible, turbulent, non-reacting flow calculations with air as the secondary injectant have been carried out. A qualitative comparison of the predictions with experimental results is made through Schlieren and Mie scattering images. A quantitative evaluation of the predictions is made by comparison with experimentally measured exit stagnation pressure, wall static pressure and the degree of unmixedness. Based on these results, three strut configurations have been selected for carrying out simulations with hydrogen as the injectant. Results from the hydrogen simulations are compared with the predictions using air and also across the strut configurations. The results clearly demonstrate that castellated strut configurations are very effective in enhancing mixing in such high speed flows.

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Light Amplification By Biofilm And Its Polarization Dependence

10.1101/139741 ◽

2017 ◽

Author(s):

Sanhita Ray ◽

Anjan Kr Dasgupta

Keyword(s):

Rayleigh Scattering ◽

Scattered Light ◽

Monochromatic Light ◽

Pore Wall ◽

Mie Scattering ◽

Photonic Devices ◽

Light Amplification ◽

Enhancement Factors ◽

Pore Wall Thickness

AbstractWe report amplified, transmitted light intensity, compared to input, when photosynthetic biofilms were placed in the path of Rayleigh scattered, monochromatic light. Enhancement spectrum shows peak at around 505 nm, which corresponds to the pore wall thickness in biofilm ultra-structure, suggesting role of resonant Mie scattering. Enhancement factors differed when biofilms from different stages of growth were used. Enhancement factors were found to depend on the nature of Rayleigh scattering liquid. Polarizing Rayleigh scattered light by the use of polarizers affected the percentage of enhancement. Amplified output is achievable with constructive interference arising out of coherent forward light scattering, a theoretically predicted outcome of Anderson localization of photons. Possible uses of photosynthetic biofilms in organic material based photonic devices have been discussed.

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D-BRANES AND KRAMERS-WANNIER DUALITY IN NON-CRITICAL SUPERSTRING THEORY

International Journal of Modern Physics A ◽

10.1142/s0217751x08040950 ◽

2008 ◽

Vol 23 (14n15) ◽

pp. 2249-2250

Author(s):

HIROTAKA IRIE

Keyword(s):

Field Theory ◽

Explicit Form ◽

Wave Functions ◽

Matter Wave ◽

Superstring Theory ◽

Superconformal Field Theory ◽

Consistency Conditions ◽

Boundary States

We study boundary states in (p,q) minimal superstring theory, combining the explicit form of matter wave functions. Within the modular bootstrap framework, Cardy states of (p, q) minimal superconformal field theory are completely determined in both cases of the different supercharge combinations, and the remaining consistency checks in the super-Liouville case are also performed. Using these boundary states, we determine the explicit form of FZZT- and ZZ-brane boundary states both in each GSO projection. Annulus amplitudes of FZZT branes are evaluated and principal FZZT branes are identified. In particular, we found that these principal FZZT branes do not satisfy Cardy's consistency conditions for each other and play a role of order/disorder parameters of a Kramers-Wannier duality in spacetime of this superstring theory. This presentation is based on the paper1.

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Mie scattering and the Martian atmosphere

Symposium - International Astronomical Union ◽

10.1017/s0074180900102712 ◽

1971 ◽

Vol 40 ◽

pp. 156-165

Author(s):

Walter G. Egan ◽

Kenneth M. Foreman

Keyword(s):

Radio Occultation ◽

Martian Atmosphere ◽

Mie Scattering ◽

Index Of Refraction ◽

Viewing Angle ◽

Angle Dependence ◽

Bulk Solid ◽

Visual Range ◽

Complex Index Of Refraction

It has been suggested that the discrepancy between radio occultation determinations of the Martian atmospheric surface pressure (3.8 to 7 mb) and those deduced from optical polarization measurements and a simple Rayleigh atmosphere model (about 10 mb) are the results of sub-micron sized aerosols in the Martian atmosphere. Based on observed viewing angle dependence of the polarization of the Martian disk in the visual range, a Mie scattering analysis has been made utilizing the measured complex index of refraction of limonite and bulk solid CO2. The results of this study indicate that limonite aerosols alone are unsatisfactory to explain the viewing angle observations, whereas solid CO2 (and H2O ice) aerosol spheres, having a dominant particle radius range between 0.28 and 0.35 μ, could bring planetary and laboratory observations into compatibility. It is suggested, further, that solid CO2 aerosols could explain limb brightening in the blue spectral range. Various distributions of solid CO2 and H2O Mie particles with radii up to 0.35 μ show an opposition effect. However, the role of these aerosols in explaining the Mars opposition observations is very dependent on the optical properties of the underlying Mars surface material.

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Engineering heat transport in nanoparticle-in-alloy composites: The role of Mie scattering

Journal of Applied Physics ◽

10.1063/1.5079231 ◽

2019 ◽

Vol 125 (14) ◽

pp. 145103 ◽

Cited By ~ 1

Author(s):

Joseph P. Feser

Keyword(s):

Heat Transport ◽

Mie Scattering

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BOUNDARY DYNAMICS IN DILATON GRAVITY

Modern Physics Letters A ◽

10.1142/s0217732394002938 ◽

1994 ◽

Vol 09 (33) ◽

pp. 3105-3117 ◽

Cited By ~ 10

Author(s):

SUMIT R. DAS ◽

SUDIPTA MUKHERJI

Keyword(s):

Total Energy ◽

Finite Interval ◽

Critical Value ◽

Matter Wave ◽

Conformal Anomaly ◽

Dilaton Gravity ◽

Matter Energy ◽

Reparametrization Invariance ◽

Boundary Dynamics

We study the dynamics of the boundary in two-dimensional dilaton gravity coupled to N massless scalars. We rederive the boundary conditions of Refs. 1 and 3 in a way which makes the requirement of reparametrization invariance and the role of conformal anomaly explicit. We then study the semiclassical behavior of the boundary in the N = 24 theory in the presence of an incoming matter wave with a constant energy flux spread over a finite interval. There is a critical value of the matter energy density below which the boundary is stable and all the matter is reflected back. For energy densities greater than this critical value there is a similar behavior for small values of the total energy thrown in. However, when the total energy exceeds another critical value the boundary exhibits a runaway behavior and the space-time develops singularities and horizons.

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