Transport phenomena

About: Transport phenomena is a research topic. Over the lifetime, 4768 publications have been published within this topic receiving 136132 citations. The topic is also known as: transport theory.

The Thermodynamics of Irreversible Processes. III. Relativistic Theory of the Simple Fluid

Abstract: The considerations of the first paper of this series are modified so as to be consistent with the special theory of relativity. It is shown that the inertia of energy does not obviate the necessity for assuming the conservation of matter. Matter is to be interpreted as number of molecules, therefore, and not as inertia. Its velocity vector serves to define local proper-time axes, and the energy momentum tensor is resolved into proper-time and -space components. It is shown that the first law of thermodynamics is a scalar equation, and not the fourth component of the energy-momentum principle. Temperature and entropy also prove to be scalars. Simple relativistic generalizations of Fourier's law of heat conduction, and of the laws of viscosity are obtained from the requirements of the second law. The same considerations lead directly to the accepted relativistic form of Ohm's law.

Some measurements in the self preserving jet

Abstract: The axisymmetric turbulent incompressible and isothermal jet was investigated by use of linearized constant-temperature hot-wire anemometers. It was established that the jet was truly self-preserving some 70 diameters downstream of the nozzle and most of the measurements were made in excess of this distance. The quantities measured include mean velocity, turbulence stresses, intermittency, skewness and flatness factors, correlations, scales, low-frequency spectra and convection velocity. The r.m.s. values of the various velocity fluctuations differ from those measured previously as a result of lack of self-preservation and insufficient frequency range in the instrumentation of the previous investigations. It appears that Taylor's hypothesis is not applicable to this flow, but the use of convection velocity of the appropriate scale for the transformation from temporal to spatial quantities appears appropriate. The energy balance was calculated from the various measured quantities and the result is quite different from the recent measurements of Sami (1967), which were obtained twenty diameters downstream from the nozzle. In light of these measurements some previous hypotheses about the turbulent structure and the transport phenomena are discussed. Some of the quantities were obtained by two or more different methods, and their relative merits and accuracy are assessed.

On Quantum Theory of Transport Phenomena Steady Diffusion

Abstract: A general formulation is given to the quantum theory of steady diffusion. In seeking for a steady solution of Liouville's equation, the boundary condition is taken into account by requiring that the solution should lead to a given distribution of average density. The distribution is to be determin­ ed by macroscopic law of diffusion and macroscopic boundary condition. The basic equation thus obtained has a form similar to Bloch's kinetic equation and reduces to the latter in the limit of a system of weakly interacting particles. This is shown by generalizing a damping theoretical expansion of Kohn and Luttinger. It is found that the Einstein relation is valid only for the symmetric part of diffusion- and electric conductivity tensors, in agreement with Kasuya's suggestion.

Combustion: Physical and Chemical Fundamentals, Modelling and Simulation, Experiments, Pollutant Formation

Abstract: Introduction * Fundamental Definitions and Phenomena * Experimental Investigation of Flames * Mathematical Description of Premixed Laminar Flat Flames * Thermodynamics of Combustion Processes * Transport Phenomena * Chemical Kinetics * Reaction Mechanisms * Laminar Prefixed Flames * Laminar Nonpremixed Flames * Ignition Processes * The Navier-Stokes Equations for Three-Dimensional Reacting Flows * Turbulent Reacting Flows * Turbulent Nonpremixed Flames * Turbulent Premixed Flames * Combustion of Liquid and Solid Fuels * Low-Temperature Oxidation, Engine Knock * Formation of Nitric Oxides * Formation of Hydrocarbons and Soot.

Advanced Transport Phenomena: Fluid Mechanics and Convective Transport Processes

Abstract: Advanced Transport Phenomena is ideal as a graduate textbook. It contains a detailed discussion of modern analytic methods for the solution of fluid mechanics and heat and mass transfer problems, focusing on approximations based on scaling and asymptotic methods, beginning with the derivation of basic equations and boundary conditions and concluding with linear stability theory. Also covered are unidirectional flows, lubrication and thin-film theory, creeping flows, boundary layer theory, and convective heat and mass transport at high and low Reynolds numbers. The emphasis is on basic physics, scaling and nondimensionalization, and approximations that can be used to obtain solutions that are due either to geometric simplifications, or large or small values of dimensionless parameters. The author emphasizes setting up problems and extracting as much information as possible short of obtaining detailed solutions of differential equations. The book also focuses on the solutions of representative problems. This reflects the book's goal of teaching readers to think about the solution of transport problems.