Turbulence dissipation rate derivation for meandering occurrences in a stable planetary boundary layer

A new formulation for the turbulence dissipation rate ε occurring in meandering conditions has been presented. The derivation consists of a MacLaurin series expansion of a lateral dispersion parameter that represents cases in which turbulence and oscillatory movements associated to the meandering events coexist. The new formulation presents the identical physical premises contained in the classical and largely used one, but the new formulation derived from meandering situations is expressed in terms of the loop parameter <I>m</I> that controls the absolute value of the negative lobe in the meandering autocorrelation function. Therefore, the <I>m</I> magnitude regulates the turbulence dissipation rate. This dissipation rate decreases for cases in which turbulence and low frequency horizontal wind oscillations coexist and increases for a fully developed turbulence. Furthermore, a statistical comparison to observed concentration data shows that the alternative relation for the turbulent dissipation rate occurring in situations of meandering enhanced dispersion is suitable for applications in Lagrangian Stochastic dispersion models

Stochastic Wind Profiles Determination for Radioactive Substances Released from Nuclear Power Plants

In this review we discuss a stochastic turbulent wind proï¬le based on the three-dimensional stochastic Langevin equation for Gram-Chalier probability density function and a known mean wind velocity. Its solution permits to simulate radioactive substances dispersion in a turbulent regime, which is of interest for nuclear reactor accident scenarios and their related emergency actions. We discuss the stochastic Langevin equation together with an analytical method for solving the three-dimensional and time dependent equation which is then applied to radioactive substance dispersion for a stochastic turbulence model. The solution is obtained using the Adomian Decomposition Method, which provides a direct scheme for solving the problem without the need for linearisation and any transformation. The results of the model are compared to case studies with measured data and further compared to procedures and predictions from other approaches

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

Nuclear Power

The world of the twenty first century is an energy consuming society. Due to increasing population and living standards, each year the world requires more energy and new efficient systems for delivering it. Furthermore, the new systems must be inherently safe and environmentally benign. These realities of today's world are among the reasons that lead to serious interest in deploying nuclear power as a sustainable energy source. Today's nuclear reactors are safe and highly efficient energy systems that offer electricity and a multitude of co-generation energy products ranging from potable water to heat for industrial applications. The goal of the book is to show the current state-of-the-art in the covered technical areas as well as to demonstrate how general engineering principles and methods can be applied to nuclear power systems

Nuclear Power

The world of the twenty first century is an energy consuming society. Due to increasing population and living standards, each year the world requires more energy and new efficient systems for delivering it. Furthermore, the new systems must be inherently safe and environmentally benign. These realities of today's world are among the reasons that lead to serious interest in deploying nuclear power as a sustainable energy source. Today's nuclear reactors are safe and highly efficient energy systems that offer electricity and a multitude of co-generation energy products ranging from potable water to heat for industrial applications. The goal of the book is to show the current state-of-the-art in the covered technical areas as well as to demonstrate how general engineering principles and methods can be applied to nuclear power systems

Proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress

Published proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress, hosted by York University, 27-30 May 2018