2009. № 35

Mathematics. Physics. Mechanics

Golovnev I. G., Platov S. A.

The popular low Reynolds turbulence model of k-ε Lam-Bramhorst is modified by the inclusion of the model of pressure-velocity diffusion into the equation of turbulence energy transfer; it allowed to forecast the laminar turbulent transfer in the boundary layer with the accuracy sufficient for engineering operations.  The pressure-velocity diffusion model is a non-gradient type looks as dpv/dy=Cpv*d(kU)/dy (dpv/dy integral on the layer cutting is equal to zero, dpv/dy=0 in turbulent homogeneous non-shear flow) with Cpv constant coefficient.

Keywords: Turbulence model; turbulent energy; pressure-velocity diffusion; laminar-turbulent transition

Khrapko R. I.

In the frame of the standard electrodynamics, a torque is calculated, which acts from a circularly polarized electromagnetic beam with a plane phase front on an absorbing surface. And a moment of momentum flux in the same beam is calculated in the frame of the same electrodynamics. It is found that this torque is twice more than the moment of momentum flux. We have inferred that the calculation of the electromagnetic angular momentum flux in the beam is incorrect. Namely, this calculation takes only a moment of momentum into account as an angular momentum, and does not take account of spin. An analysis of the field theory foundations of the electrodynamics confirms this inference. Some changes in the field theory allow to obtain an electrodynamics’ spin tensor, which accompanies the Maxwell energy-momentum tensor. Using this spin tensor for the beam yields the equality between the torque and the angular momentum flux. In this way, the electrodynamics is completed by a spin tensor.

Keywords: electrodynamics torque; angular momentum; spin tensor

Khrapko R. I.

An interference experiment is proposed to answer a troubling question, how is angular momentum flux density is ditributed over a circularly polarized light beam with plane phase front.

Keywords: electrodynamics spin; electrodynamics torque; Mach-Zehnder interferometr

Khrapko R. I.

The concept is criticized about quasi-elastic dipoles of dielectric which are being stretched out when polarizing.

Keywords: model of dielectric molecules; Stark effect

Khrapko R. I.

Reasons are presented against considering a moment of momentum flux density to be a spin flux density. A spin tensor is proposed to describe spin of a photon in the frame of the classical electrodynamics.

Keywords: paraxial beam; dipole radiation; spin radiation

Theoretical engineering. Mechanical engineering

Kulik Y. P., Fedorov I. A.

Development of the interconnected system of the working documentation is the primary goal of technical preproduction of any industrial product. Quality of development process of the design, technological and operational documentation first of all will define the quality of turned-out products. For mechanical items with an operated configuration this process possesses the specificity.
In this work the organizational and technical system of creation of the working documentation is described with use of methodology of functional modeling IDEF0, and also processes of management of mechanical items configuration are identified within the limits of this system.

Keywords: IDEF0 methodology; working documentation; technical preproduction; configuration management of the mechanical details

Kulik Y. P., Fedorov I. A.

Application of coprojectization technology by all participants of product life cycle, known as "parallel engineering", is the necessary condition of the product quality improvement, decrease in time and material costs. First of all it is reached by realization of the most effective administrative decisions at all stages of technical preproduction, based on fullest account of the opinions of all experts, participants of the project. Process of making up of project decisions at such approach is called as management of the product configuration.
In this work general approaches to management of the configuration of mechanical details are considered. As a final goal this configuration has the creation of the interconnected system of details' design, technological and operational documentation.

Keywords: parallel engineering; configuration management; technical preproduction; working documentation

Methods and tutorials

Nabatova D. S.

The description of a computer practical work for students and bachelors МАI on computing algorithm Lemke-Howson of the decision bimatrix games is stated in article. The basic aspects of calculations and an example with representation of working windows of the program are considered.

Keywords: training programs; a computer practical work; computing algorithm; the software; the multiwindow environment; an example of calculations

Electrotechnology. Electromechanics

Antonov Y. F.

The structure and dynamic superconductor’s intermediate and mixed states of are described, including its cooperation and electromagnetic effects. It is briefly discussed the design of the 2G HTS topological generator and experimental results.

Keywords: high temperature superconductor; intermediate and mixed states cooperation; topological generator; design; experiment

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