Author: J. R. RistorcelliPublisher:
ISBN:
Category :
Languages : en
Pages : 30
Book Description
Some Results Relevant to Statistical Closures for Compressible Turbulence
Author: J. R. RistorcelliSome Results Relevant to Statistical Closures for Compressible Turbulence
Author: Joseph Raymond RistorcelliPublisher:
ISBN:
Category :
Languages : en
Pages : 32
Book Description
Modeling Complex Turbulent Flows
Author: Manuel D. SalasPublisher: Springer Science & Business Media
ISBN: 9401147248
Category : Science
Languages : en
Pages : 385
Book Description
Turbulence modeling both addresses a fundamental problem in physics, 'the last great unsolved problem of classical physics,' and has far-reaching importance in the solution of difficult practical problems from aeronautical engineering to dynamic meteorology. However, the growth of supercom puter facilities has recently caused an apparent shift in the focus of tur bulence research from modeling to direct numerical simulation (DNS) and large eddy simulation (LES). This shift in emphasis comes at a time when claims are being made in the world around us that scientific analysis itself will shortly be transformed or replaced by a more powerful 'paradigm' based on massive computations and sophisticated visualization. Although this viewpoint has not lacked ar ticulate and influential advocates, these claims can at best only be judged premature. After all, as one computational researcher lamented, 'the com puter only does what I tell it to do, and not what I want it to do. ' In turbulence research, the initial speculation that computational meth ods would replace not only model-based computations but even experimen tal measurements, have not come close to fulfillment. It is becoming clear that computational methods and model development are equal partners in turbulence research: DNS and LES remain valuable tools for suggesting and validating models, while turbulence models continue to be the preferred tool for practical computations. We believed that a symposium which would reaffirm the practical and scientific importance of turbulence modeling was both necessary and timely.
Transition, Turbulence and Combustion Modelling
Author: A. HanifiPublisher: Springer Science & Business Media
ISBN: 9401145156
Category : Science
Languages : en
Pages : 540
Book Description
This single-volume work gives an introduction to the fields of transition, turbulence, and combustion modeling of compressible flows and provides the physical background for today’s modeling approaches in these fields. It presents basic equations and discusses fundamental aspects of hydrodynamical instability.
Engineering Turbulence Modelling and Experiments - 4
Author: D. LaurencePublisher: Elsevier
ISBN: 0080530982
Category : Science
Languages : en
Pages : 975
Book Description
These proceedings contain the papers presented at the 4th International Symposium on Engineering Turbulence Modelling and Measurements held at Ajaccio, Corsica, France from 24-26 May 1999. It follows three previous conferences on the topic of engineering turbulence modelling and measurements. The purpose of this series of symposia is to provide a forum for presenting and discussing new developments in the area of turbulence modelling and measurements, with particular emphasis on engineering-related problems. Turbulence is still one of the key issues in tackling engineering flow problems. As powerful computers and accurate numerical methods are now available for solving the flow equations, and since engineering applications nearly always involve turbulence effects, the reliability of CFD analysis depends more and more on the performance of the turbulence models. Successful simulation of turbulence requires the understanding of the complex physical phenomena involved and suitable models for describing the turbulent momentum, heat and mass transfer. For the understanding of turbulence phenomena, experiments are indispensable, but they are equally important for providing data for the development and testing of turbulence models and hence for CFD software validation.
Scientific and Technical Aerospace Reports
Author: Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 376
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Progress in Favre-Reynolds Stress Closures for Compressible Flows
Author: Virgil AdumitroaiePublisher:
ISBN:
Category :
Languages : en
Pages : 48
Book Description
A closure for the compressible portion of the pressure strain covariance is developed. It is shown that, within the context of a pressure strain closure assumption linear in the Reynolds stresses, an expression for the pressure dilatation can be used to construct a representation for the pressure strain. Additional closures for the unclosed terms in the Favre Reynolds stress equations involving the mean acceleration are also constructed. The closures accommodate compressibility corrections depending on the magnitude of the turbulent Mach number, the mean density gradient, the mean pressure gradient, the mean dilatation, and, of course, the mean velocity gradients. The effects of the compressibility corrections are consistent with current DNS results. Using the compressible pressure strain and mean acceleration closures in the Favre Reynolds stress equations an algebraic closure for the Favre Reynolds stresses is constructed. Noteworthy is the fact that, in the absence of mean velocity gradients, the mean density gradient produces Favre Reynolds stresses in accelerating mean flows. Computations of the mixing layer using the compressible closures developed are described. Favre Reynolds stress closure and two equation algebraic models are compared to laboratory data. The mixing layer configuration computations are compared to laboratory data; since the laboratory data for the turbulence stresses is inconsistent, this comparison is inconclusive. Comparisons for the spread rate reduction indicate a sizable decrease in the mixing layer growth rate.
Monthly Catalog of United States Government Publications
Author: Closure Strategies for Turbulent and Transitional Flows
Author: Brian Edward LaunderPublisher: Cambridge University Press
ISBN: 9780521792080
Category : Mathematics
Languages : en
Pages : 774
Book Description
Publisher Description
Variable Density Fluid Turbulence
Author: P. ChassaingPublisher: Springer Science & Business Media
ISBN: 9401700753
Category : Science
Languages : en
Pages : 387
Book Description
The first part aims at providing the physical and theoretical framework of the analysis of density variations in fully turbulent flows. Its scope is deliberately educational. In the second part, basic data on dynamical and scalar properties of variable density turbulent flows are presented and discussed, based on experimental data and/or results from direct numerical simulations. This part is rather concerned with a research audience. The last part is more directly devoted to an engineering audience and deals with prediction methods for turbulent flows of variable density fluid. Both first and second order, single point modeling are discussed, with special emphasis on the capability to include specific variable density / compressibility effects.