Observation of quasi-coherent density fluctuation in scrape-off layer enhancing boundary transport in high-βN hybrid plasmas on DIII-D

This paper is devoted to the analysis of the turbulent mass flux and, more generally, of the density fluctuation correlation (d.f.c.) effects in variable-density fluid motion. The situation is restricted to the free turbulent binary mixing of an inhomogeneous round jet discharging into a quiescent atmosphere. Based on conventional (Reynolds) averaging, a ternary regrouping of the correlations occurring in the statistical averaging of the open equations is first introduced. Then an exact algebraic relationship between the d.f.c. terms and the second-order moments is demonstrated. Some consequences of this result on the global behaviour of variable-density jets are analytically discussed. The effects of the d.f.c. terms are shown to give a qualitative explanation of the influence of the ratio of the densities of the inlet jet and ambient fluid on the centerline decay rates of mean velocity and mass fraction, the entrainment rate and the restructuring of the jet. Finally, the sensitivity of second-order modelling to the d.f.c. terms is illustrated and it is suggested that such terms should be considered as independent variables in the closing procedure.

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Frequency Resolved Density Fluctuation Measurements of Combustion Oscillations in a Model Combustor

49th AIAA/ASME/SAE/ASEE Joint Propulsion Conference ◽

10.2514/6.2013-3667 ◽

2013 ◽

Author(s):

Johannes J. Peterleithner ◽

Andreas Marn ◽

Thomas Leitgeb ◽

Jakob Woisetschläger

Keyword(s):

Density Fluctuation

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NATURAL ORBITALS AND ELECTRON ELASTIC MAGNETIC SCATTERING BY NUCLEI

International Journal of Modern Physics E ◽

10.1142/s0218301396000396 ◽

1996 ◽

Vol 05 (04) ◽

pp. 717-724 ◽

Cited By ~ 4

Author(s):

D.N. KADREV ◽

A.N. ANTONOV ◽

M.V. STOITSOV ◽

S.S. DIMITROVA

Keyword(s):

Density Fluctuation ◽

Form Factors ◽

Wave Functions ◽

Magnetic Scattering ◽

Correlation Effects ◽

Valence Nucleon ◽

Nucleon System ◽

Natural Orbitals ◽

Transverse Form Factor ◽

Fluctuation Model

Natural orbitals obtained within the coherent density fluctuation model and containing nucleon correlation effects are used to calculate characteristics of the A-nucleon system, such as the electron elastic magnetic scattering form factors. The calculations are performed for nuclei with a doubly-closed core and a valence nucleon in a stretched configuration (j=l+1/2), such as the 17 O and 41 Ca nuclei. It is shown that the calculations of the transverse form factor using natural orbitals improve the agreement with the experimental data in comparison with the case when shell-model single-particle wave functions are used.

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Evaluated Excited-State Time-Independent Correlation Function and Eigenfunction of the Harmonics Oscillator Cosine Asymmetric Potential via Numerical Shooting Method

Physics Research International ◽

10.1155/2015/609495 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Artit Hutem ◽

Piyarut Moonsri

Keyword(s):

Correlation Function ◽

Density Fluctuation ◽

Shooting Method ◽

State Energy ◽

Energy Eigenvalue ◽

Computational Effort ◽

Atomic Density ◽

Excite State ◽

Numerical Shooting Method ◽

Problem Comparison

We aimed to evaluate the ground-state and excite-state energy eigenvalue (En), wave function, and the time-independent correlation function of the atomic density fluctuation of a particle under the harmonics oscillator Cosine asymmetric potential (Saad et al. 2013). Instead of using the 6-point kernel of 4 Green’s function (Cherroret and Skipetrov, 2008), averaged over disorder, we use the numerical shooting method (NSM) to solve the Schrödinger equation of quantum mechanics system with Cosine asymmetric potential. Since our approach does not use complicated formulas, it requires much less computational effort when compared to the Green functions techniques (Cherroret and Skipetrov, 2008). We show that the idea of the program of evaluating time-independent correlation function of atomic density is underdamped motion for the Cosine asymmetric potential from the numerical shooting method of this problem. Comparison of the time-independent correlation function obtained from numerical shooting method by Boonchui and Hutem (2012) and correlation function experiment by Kasprzak et al. (2008). We show the intensity of atomic density fluctuation (δn(x)=n~(x)-m~(x)) in harmonics oscillator Cosine asymmetric potential by numerical shooting method.

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