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971.
A large eddy simulation (LES) is performed for turbulent flow around a bluff body inside a sudden expansion cylinder chamber,
a configuration which resembles a premixed gas turbine combustor. To promote turbulent mixing and to accommodate flame stability,
a flame holder is installed inside the combustion chamber. The Smagorinsky model and the Lagrangian dynamic subgrid-scale
model are employed and tested. The calculated Reynolds number is 5,000 based on the bulk velocity and the diameter of inlet
pipe. The simulation code is constructed by using a general coordinate system based on the physical contravariant velocity
components. The predicted turbulent statistics are evaluated by comparing with the laser-doppler velocimetry (LDV) measurement
data. The agreement of LES with the experimental data is shown to be satisfactory. Emphasis is placed on the time-dependent
evolutions of turbulent vortical structures behind the flame holder. The numerical flow visualizations depict the behavior
of large-scale vortices. The turbulent behavior behind the flame holder is analyzed by visualizing the sectional views of
vortical structure.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
972.
In this paper, 2-adic complexity of some binary sequences with interleaved structure is investigated. Firstly, 2-adic complexity of low correlation zone (LCZ) sequences constructed by Zhou et al. [23] is completely determined. We show that their 2-adic complexity could attain the maximum if suitable parameters are chosen. Secondly, we also determine 2-adic complexity of optimal autocorrelation sequences constructed by Tang and Ding [16]. Results show that they have the maximum 2-adic complexity. 相似文献
973.
Let p≥7 be an odd prime. Based on the Toda bracket α1βp-11, α1 β1, p, γs,the authors show that the relation α1βp-11h2,0 γs= βp/p-1γs holds. As a result, they can obtain α1βp1h2,0 γs = 0 ∈π*(S0) for 2≤s≤p- 2, even though α1h2,0γs and β1α1h2,0 γs are not trivial. They also prove that βp-11α1 h2,0 γ3 is nontrivial in π*(S0) and conjecture that βp-11α1 h2,0 γs is nontrivial in π*(S0) for 3≤s≤p- 2. Moreover, it is known thatβp/p-1γ3 = 0 ∈ Ext5,*BP*BP(BP*, BP*), but βp/p-1γ3 is nontrivial in π*(S0) and represents the element βp-11α1 h2,0 γ3. 相似文献
974.
《代数通讯》2013,41(4):965-986
ABSTRACT An exact sequence of Witt groups, motivated by exact sequences obtained by Lewis and by Parimala, Sridharan and Suresh, is constructed. The behavior of the maps involved in these sequences with respect to isotropy is completely determined in the case of division algebras. In particular, the kernels of the maps involved in the previous sequences are explicitly given, leading to a new proof of their exactness. Similar exact sequences of equivariant Witt groups are constructed. As an application, relations between the cardinality of certain Witt groups are obtained. 相似文献
975.
976.
Zeng Liu-chuan 《应用数学和力学(英文版)》2002,23(6):686-693
The convergence of theIshikawa iteration sequences with errors for constructing solutions of m-accretive operator equations
is characterized. Moreover, the error estimates of approximate solutions for locally Lipschitzian and m-accretive operator
equations are established.
Foundation items: the National Natural Science Foundation of China (19801023); the Teaching and Research Award Fund for Outstanding Young
Teachers in Higher Education Institutions of MOE, China
Biography: ZENG Liu-chuan (1965-), Professor 相似文献
977.
Two parameterizations of oblique duals of a given frame sequence are applied to show that the sum of a frame sequence and one of its oblique duals may not be a frame sequence, and that type II dual is locally (and globally) optimal in some sense and that the excesses of the frame sequence and its oblique duals are the same. Other observations on the duals of a frame sequence are included also. 相似文献
978.
979.
Vakeel A. Khan Kamal M. A. S. Alshlool Sameera A. A. Abdullah 《Numerical Functional Analysis & Optimization》2013,34(12):1278-1290
AbstractThe notation of I–convergence was introduced and studied by Kostyrko, Macaj, Salat, and Wilczynski. Recently, the concept of I–convergent for a sequence of bounded linear operators has been studied by Khan and Shafiq. This has motivated us to introduce and study some new spaces of double sequences of bounded linear operators and their basic topological and algebraic properties of these spaces. And we study some of their basic topological and algebraic properties of these spaces. We prove some inclusion relations on these spaces. 相似文献
980.