On an air quality and odor modeling system for CMPC Celulose Riograndense

The present work is part of the research project that aims to create an automated system for the evaluation of air pollution and odour for CMPC CELULOSE RIOGRANDENSE. Initially, three different ways of initializing the CALPUFF model (one of the models under evaluation to compose the system) were evaluated. The results when compared with observational data on air quality suggest the need for a validation of the boundary conditions and turbulent scale parameters in the hourly time representation when CALPUFF is the model being used. The choice was not random, but based on three quantities that impose physical affinity to micrometeorological data. The surface roughness, the albedo and the Bowen ratio. Changes in these quantities were imposed during pre-processing of AERMET, which established the quantities of interest in a simulation of dispersion of pollutants. After this alternative the results become more representative for the atmospheric dispersion process. The monthly and annual representation of the CALPUFF model is satisfactory without validation procedure

Self-reciprocal fermion mass ratios from massless QED with curved momentum space

The present investigation is an attempt to understand the fermion mass ratios in the framework of QED of charged fermions without a bare mass. Since QED of massless charged fermions is invariant under the dilatation transformation, this symmetry has to be spontaneously broken to obtain massive fermions. In the proposed model we combine a mass-scale normalisation with the renormalisation procedure, assuming the fermion momentum space being a four-dimensional one-shell hyperboloid embedded in a five-dimensional space. The hyperboloid constrains the allowed fermion field solutions. We construct the theory in the conventional way using equal time anti-commutator and the Lagrangian formalism. Starting from the Dyson–Schwinger equation for fermion propagator in the Landau gauge, we derive the fermion mass function and self-reciprocal solutions for the mass ratios, which are independent of any constant

On a model for pollutant dispersion in the atmosphere with partially reflective boundary conditions and data simulation using CALPUFF

The present work is an attempt to simulate the dispersion of pollutants in the surroundings of the thermoelectric plant located in Linhares from a new mathematical model based on partially reflective boundaries in the deterministic advection-diffusion equation. In addition to the advection-diffusion equation with partially reflective boundaries, it was used data simulated with the CALPUFF model. The exposed model was validated previously with the Hanford and Copenhagen experiments and the results indicate that effects on the boundaries are essential to model dispersion phenomenona in the atmospheric boundary layer

On the identification of the contribution of several pollutant sources from local

In the present article we discuss the pollution dispersion problem from a mixed juridical scientific technological point of view, where the principal interest lies in the pertinent question, how to transform model simulation and analysis tools into an operational tool. One evaluation method relevant for control, planning, licensing and commissioning of installations that are the origin of pollution is discussed, where observational shortcomings and the role of model simulations are addressed. We briefly review deterministic and stochastic models, complement it by some aspects concerning the pollution problem in the context of urban growth and indicate the necessity for a symbiosis of legislation and scientific-technical measures. A method is proposed that allows to optimise monitoring as well as simulations combined by mutual feedback in order to create a reliable base for decisions in the context of legal actions. The authors of the present article are aware that the presented discussion is only one step in a direction where legislation and the scientific and technological sector work hand in hand in order to make progress on the subject

Curvilinear coordinate system used to solve tritium dispersion in complex orographies

In this contribution we present progress on research concerning dispersion of tritium around the Angra Nuclear Power Plant (Angra dos Reis, Rio de Janeiro state, Brazil). In particular, we are interested in studying how dispersion behaves in scenarios with complex orography. Our proposal is to transform a problem with curvilinear boundaries into an equivalent problem with plane parallel boundaries. We modify the coordinate system through a diffeomorph conformal transformation. Consequently, the operators of the dynamical equations change according to the additional terms from the affine connection. To define the transformation it is necessary to satisfy strong constraints, i.e., boundaries shall be “smooth”. Even with restrictions, our model can be implemented in several situations. A flat region is a particular case of a curvilinear domain and can be studied, where the height of the boundary layer above rivers, lakes, basins is typically smaller and thus implies a varying boundary layer height, for example. Thus, even in flat regions variations in the boundary layer occur, which characterizes a case of a curvilinear domain. There are several nuclear power plants worldwide, that are located in mountainous regions, as for example in Japan and Brazil.We present a simulation of tritium dispersion specifically in the area where the Angra 2 Nuclear Power Plant is located and where the relief is characterized by a considerable complexity. With the intention of showing that the methodology is consistent, we will consider only the variation of the relief

A genuine solution of the diffusion advection equation sesquilinear way to multi-source problem

The present work is a proposal for an alternative approach for pollution dispersion modelling, including some characteristics that may be associated to the phenomenon of turbulence. As a starting point we consider two axiomatic properties that shall lead to a model and its solution compatible with distributional descriptions. The first one states that a solution shall be semi-positive as expected for a distribution, whereas the second axiom demands for compatibility with coherent structures, which are implemented by the use of sesquilinear forms

On a model for pollutant dispersion in the atmosphere with partially reflective boundary conditions

The present work is an attempt to simulate stochastic effects in a deterministic model for pollutant dispersion in the atmospheric boundary layer by the use of a probability weighted boundary condition. More specifically, the escape of pollutant substances across the boundary layer horizon on the one side and the surface boundary on the other side are modelled by probabilities to quantify the fraction of pollutant that returns into the boundary layer from above and the process of adsorption or deposition on the ground layer. These effects are represented by partially reflective boundary conditions that together with advection-diffusion dispersion define the model in consideration. The consequences of the reflections are analysed using the meteorological conditions and data of the Hanford and Copenhagen experiments. A variety of trials have shown that partial reflection on the boundary layer horizon and the ground, respectively, obtain the most significant correlations between model and data suggesting that effects on the boundary are essential to model dispersion processes in the atmospheric boundary layer

The radiative conductive transfer equation in cylinder geometry : rocket launch exhaust phenomena for the Alcântara Launch Center

In this work we present a solution for the radiative conductive transfer equation in cylinder geometry for a solid cylinder. We discuss a semi-analytical approach to the non-linear N S problem, where the solution is constructed by Laplace transform and a decomposition method. The obtained solution allows then to construct the relevant near field to characterize the source term for dispersion problems when adjusting the model parameters such as albedo, emissivity, radiation conduction and others in comparison to the observation, that are relevant for far field dispersion processes and may be handled independently from the present problem. In addition to the solution method we also report some solutions and numerical simulations

On the reconstruction of concentration distributions form comparison of deterministic predictions to observational data

The dispersion of pollutants in the atmospheric boundary layer is a stochastic process but many approaches make use of deterministic models, such as the advection-diffusion equation, that determines average values. Comparison between observation and model prediction show a significant spread of values due to the stochastic character of the pollution dispersion phenomenon. Measured data though represent only one sample of an unknown distribution. Thus, the present article is a first attempt to reconstruct at least some of the pollutant concentration distribution properties from the comparison of deterministic predictions to observed concentrations under specific micro-meteorological conditions. The experimental data are the findings of the Copenhagen campaign. We show the scatter plot of observed versus predicted ground level concentrations from which distributional properties are extracted by determining the distance of each plot point from the bisector, proposing a parametrization for the probability function and fit the discrete set of data points. The probability density function obtainde from the probability distribution shows a narrow peak centered at zero besides a second smaller but displaced contribution. A reconstructed distribution symmetrically around zero signifies, that the model describes the average values of the distribution with fairly good fidelity and the width could be used as an approximation for the second statistical moment. The distribution which is not centered at the origin indicates either missing physics in the model, or failures in the measuring procedure. The reconstructed distribution with correlation less than one shows the aforementioned stochastic character of the phenomenon. Although applied to a specific experiment and using one deterministic model the reconstruction method is general and can be applied to other scenarios in an analogue fashion

Comparison of CALMET and WRF/CALMET coupling for dispersion of NO2 and SO2 using CALPUFF modelling system

This study aims to compare the wind and concentration field generated by a coupling of WRF/CALMET model and CALMET/CALPUFF with no introduction of any gridded wind field. The domain was located at the city of Linhares, southeast region of Brazil, with a 15×15 grid cells and 1 km resolution. The chosen modelling period was April 1st, 2011, with the length of 90 h. The pollutants simulated by CALPUFF were NO2 and SO2. The final results of dispersion and concentration peak were compared against environmental legislation of 1 h average for NO2 and 24 h average for SO2. The first simulation, using WRF/CALMET model, shows plausible results. The second mode, CALMET/CALPUFF, generated a wind field with questionable results, which probably compromised the dispersion simulation. Both model results are within environmental legislation