ENERGY AND SIZE DISTRIBUTION OF EDDIES IN TURBULENT FLOW THROUGH CIRCULAR PIPE

Abstract

Most naturally occurring fluid flows are turbulent, e.g.; atmospheric turbulence, the planetary boundary layer, clear-air turbulence and clouds; ocean currents; rivers; the photosphere of the sun; inter-stellar gas clouds; and bush fires. The same is true of most engineering flows, e.g.; boundary layers on aircraft wings, ships etc.; the wakes of ships, cars, aircraft etc.; chimney plumes; and flow in pipelines and furnaces. Many flows in everyday life and engineering are deliberately made to be turbulent, e.g.; coffee stirring, tea pouring and cocktail shaking; boundary layers on aircraft wings; the chemical process industry including food manufacture; and most combustion processes including car engines. Theories for laminar flow has matured in many ways, however, behavior of turbulent flow is still not completely understood. Present work is focusing on verifying new hypothesis considering in turbulent flow field, only eddies of discrete size are present and that each individual eddy can be considered as a separate energy packet which interact with other eddies without exchanging energy among them. And turbulent flow can be represented by the superimposing the total eddies for geometry and parabolic velocity profile. A brief outline of the work presented in this dissertation is given in the following paragraphs: Literature Survey has been given in Chapter two. In Chapter three, the Turbulent and basic Turbulence models are presented in brief Some of the research articles describe the development of turbulent model and simulation and improvements, while others describe experimental findings, which deal with work related to velocity and shear profile results, On the other hand, some of the researcher studied the eddy velocity profile experimentally which are also reported and consider for validation in chapter two. In the chapter four, eddy model equation is described which explain the velocity distribution with in eddy, then consider the eddy size to be discretized rather than the iii continuum. And given the simulation procedure for simulating the superimposed flow of one simple velocity profile and second is for the eddy velocity profile. In the fifth chapter, result and discussion is given in which simulated results and experimental results and various turbulent properties are compared. In the next chapter conclusions of this study along with some recommendations for future work are described briefly, the dissertation ends with a list of references and a few appendices. Nomenclature used in this presentation of some special terms relating the eddy and turbulent properties are provided in the beginning to assist in the understanding of the subject.