CH and C2 radicals characterization in natural gas turbulent diffusion flames

This paper reports the construction of an axisymmetric nonpremixed piloted jet burner, with well-defined initial and boundary conditions, known as the Delft burner, to assess turbulence-chemistry interaction in non-premixed turbulent flames. Detailed experimental information is described, involving hot-wire anemometry, thin-wire thermocouples and chemiluminescence visualization measurements. Radial profile of the axial mean velocity indicates excellent agreement between flow patterns developed within Delft installation and the one described herein. Chemiluminescence emissions from CH and C2 free-radicals were acquired with a CCD camera. Tomography reconstruction analysis was utilised to compare radical emissions and temperature spatial distributions. There was a strong dependence between temperature and CH/C 2 emissions. This is an indication that these radicals can be used in flame front studies.

Capital flows to emerging economies: does the emperor have clothes?

Includes bibliography

Liquidity black holes: why modern financial regulation in developed countries is making short-term capital flows to developing countries even more volatile

Includes bibliography

Derivatives, the shape of international capital flows and the virtues of prudential regulation

Includes bibliography

Capital flows in Chile: changes and policies in the 1990s

Includes bibliography

International financial flows: a labour point or view

Includes bibliography

Chaos induced by turbulent and erratic functions

Let (X, d) be a compact metric space and f: X → X a continuous function and consider the hyperspace (K(X), H) of all nonempty compact subsets of X endowed with the Hausdorff metric induced by d. Let f̄: K(X) → K (X) be defined by f̄(A) = {f(a)/a ∈ A} the natural extension of f to K(X), then the aim of this work is to study the dynamics of f when f is turbulent (erratic, respectively) and its relationships.

A summary of the experiences of Chile and Colombia with unremunerated reserve requirements on capital flows during the 1990's

Incluye Bibliografía

Private international capital flows to Brazil

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The use of molecular spectra simulation for diagnostics of reactive flows

The C 2 * radical is used as a system probe tool to the reactive flow diagnostic, and it was chosen due to its large occurrence in plasma and combustion in aeronautics and aerospace applications. The rotational temperatures of C 2 * species were determined by the comparison between experimental and theoretical data. The simulation code was developed by the authors, using C++ language and the object oriented paradigm, and it includes a set of new tools that increase the efficacy of the C 2 * probe to determine the rotational temperature of the system. A brute force approach for the determination of spectral parameters was adopted in this version of the computer code. The statistical parameter c 2 was used as an objective criterion to determine the better match of experimental and synthesized spectra. The results showed that the program works even with low-quality experimental data, typically collected from in situ airborne compact apparatus. The technique was applied to flames of a Bunsen burner, and the rotational temperature of ca. 2100 K was calculated.

International migration, capital flows and the global economy: a long run view

Includes bibliography

International capital flows to Latin America

Includes bibliography

Numerical assessment of mass conservation on a MAC-type method for viscoelastic free surface flows

A numerical study of mass conservation of MAC-type methods is presented, for viscoelastic free-surface flows. We use an implicit formulation which allows for greater time steps, and therefore time marching schemes for advecting the free surface marker particles have to be accurate in order to preserve the good mass conservation properties of this methodology. We then present an improvement by using a Runge-Kutta scheme coupled with a local linear extrapolation on the free surface. A thorough study of the viscoelastic impacting drop problem, for both Oldroyd-B and XPP fluid models, is presented, investigating the influence of timestep, grid spacing and other model parameters to the overall mass conservation of the method. Furthermore, an unsteady fountain flow is also simulated to illustrate the low mass conservation error obtained.

Development of a low-Reynolds-number k-ω model for FENE-P fluids

A low-Reynolds-number k-ω model for Newtonian fluids has been developed to predict drag reduction of viscoelastic fluids described by the FENE-P model. The model is an extension to viscoelastic fluids of the model for Newtonian fluids developed by Bredberg et al. (Int J Heat Fluid Flow 23:731-743, 2002). The performance of the model was assessed using results from direct numerical simulations for fully developed turbulent channel flow of FENE-P fluids. It should only be used for drag reductions of up to 50 % (low and intermediate drag reductions), because of the limiting assumption of turbulence isotropy leading to an under-prediction of k, but compares favourably with results from k-ε models in the literature based on turbulence isotropy. © 2012 Springer Science+Business Media Dordrecht.

Latin America and the new finance and trade flows

Includes bibliography