Bistable swirled flames and influence on flame transfer functions

Large Eddy Simulations (LES) are used to study a lean swirl-stabilized gas turbine burner where the flow exhibits two stable states. In the first one, the flame is attached to the central bluff body upstream of the central recirculation zone which contains burnt gases. In the second one the flame is detached from the central bluff body downecirculation zone which is filled by cold unburnt gases and dominated by a strong Precessing Vortex Core (PVC). The existence of these two states has an important effect on the dynamic response of the flame (FTF): both gain and phase of the FTF change significantly in the detached case compared to the attached one, suggesting that the stability of the machine to thermoacoustic oscillations will differ, depending on the flame state. Bifurcation diagrams show that the detached flame cannot be brought back to an attached position with an increased fuel flow rate, but it can be re-attached by forcing it at high amplitudes. The attached flame however, behaves inversely: it can be brought back to the detached position by both decreasing or increasing the pilot mass flow rate, but it remains attached at all forcing amplitudes.     

Extension of the Relational Algebra on the Basis of CODASYL DBTG Proposals

Cybernetics and Systems Analysis - A solution to the problem of low computational efficiency of the relational data model is investigated. An extension of the relational algebra with the help of...     

On the Raman Scattering,Infrared Absorption,and Luminescence Spectroscopy of Aluminum Nitride Doped with Beryllium

Semiconductors - The effects of the high-temperature (T = 1880°C) diffusion of beryllium ions and of electron irradiation on the optical properties of single-crystal aluminum nitride is...     

Nondestructive electromagnetic testing of hardened layers on surfaces of steel components

In order to improve the measurement accuracy of hardened layer thickness, we suggest to use combination harmonics in a signal from an attached electromagnetic transducer. The paper describes an instrument for testing a hardened layer and generating a multidimensional digitized signal characterizing this layer. Results of tests of an experimental version of the device by measuring the thickness and hardness of case-hardened layers are given.     

Irreversibility of degradation of polymer solutions

The degradation of polymer solutions of different concentration was investigated. It was found that a polymer solution that has been degraded by prolonged subjection to shear stress does not recover its drag-reducing properties after freezedrying and re-solution.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 38, No. 2, pp. 235–237, February, 1980.     

Indices of the effectiveness of information protection in an information interaction system for controlling complex distributed organizational objects

In this paper, we present some indices for evaluating the effectiveness of information protection in an information interaction system when controlling complex distributed organizational objects and proposing a technique for determining these indices. The technique is based on a stochastic representation of the flow of destructive actions that affect the information interactions among controllers of the elements of a distributed organizational object.     

Single and biphoton imaging and high dimensional quantum communication

Here, we present recent developments in the field of quantum imaging focusing on the high dimensionality aspects of single and biphoton imaging. We discuss some systems that have a ??quantum advantage?? over classical counterparts. We highlight some recent experiments in single-photon image discrimination, large alphabet quantum key distribution and image buffering.