1. INTERNATIONAL CONFERENCES

Symposium on Modeling and Simulation of Turbulent Flows

In memory of Prof. Charles G. Speziale
4th ASME/JSME Joint Fluids Engineering Conference
July 6-10, 2003 Sheraton Hotel Waikiki, Honolulu, Hawaii

The Fluid Mechanics Technical Committee (FMTC) of the Fluids Engineering Division of the ASME is sponsoring a symposium on Modeling and Simulation of Turbulent Flows in memory of Prof. Charles G. Speziale, past Professor of Aerospace and Mechanical Engineering at Boston University. The goal of the symposium is to provide an opportunity for discussion of recent advances in modeling and simulation of turbulent flows - topics that were of considerable interest to Professor Charles Speziale, and areas in which he has made fundamental and long lasting contributions. Sessions topics will include, but are not limited to the following: turbulence models for complex flows, subgrid models for LES, RANS models for unsteady flows. Contributions that benchmark accurate prediction of complex flows elucidate separation mechanisms, or present quantitative visualization of complex flow structures, are sought. Papers that present RANS models that capture anisotropy and nonequilibrium effects for accurate prediction of complex turbulent flows as well as effective models for subgrid stresses in LES are highly encouraged.

14th U.S.National Congress of Theoretical and Applied Mechanics
Symposium on

TOPICS IN THE FLOW OF COMPLEX FLUIDS

in honor & memory of

PROFESSOR CHARLES SPEZIALE

Virginia Polytechnic Institute and State University
Blacksburg, Virginia
June 23-28, 2002

Organized by

Dennis A. Siginer, Ph.D., D.Sc.
Dean, College of Engineering
Wichita State University

2. LATEST PUBLICATIONS

Publications:
Speziale and Xu, "Towards the development of second-order closure models for non-equilibrium turbulent flows," Proceedings of the 10th symposium on turbulent shear flows, Vol.3, 1995, pp. 23.7-23.12 Xu and Speziale, "Explicit Algebraic Stress Models."

Abstract from one of papers

On Non-Equilibrium Reynolds Stress Models for Complex Turbulent Flows.
John Henry X.H. Xu, Charles G. Speziale (Boston University)

There has recently emerged an interest in the development of Reynolds stress models for non-equilibrium turbulent flows. This has been motivated by the fact that many unsteady turbulent flows of engineering interest are in non-equilibrium states, and current Reynolds stress models cannot predict non-equilibrium turbulence correctly. Two types of non-equilibrium Reynolds stress models have been developed recently that will be discussed in this presentation. These consist of a non-equilibrium algebraic stress model and a non-equilibrium second-order closure model. The models are tested in non-equilibrium homogeneous turbulent shear flow. It is found that by using the new non-equilibrium algebraic stress model and second-order closure, results are obtained that compare favorably with those obtained from direct numerical simulations and RDT. It is furthermore shown that current second-order closures -- as well as a recently developed non-equilibrium model based on elliptic relaxation -- are simply not consistent with the general behavior of non-equilibrium turbulent shear flows. It is argued that the coefficients in second-order closures should be made functions of the non-dimensional mean strain-rates and mean rotation-rates. Applications of these non-equilibrium Reynolds stress models to complex turbulent flows are briefly discussed.

3. REMEMBERED BY SCIENTISTS

He will be remembered by scientist working on turbulence.