Vol 51, No 1 (2017)

A general description of the program of complex modernization of the Votkinsk Hydroelectric Power Plant is presented and the target guideposts and innovative designs which are used in its implementation are described.

A brief description of the several stages in the introduction of automatic control systems at the Votkinsk Hydroelectric Power Plant from 1962 until the present day is given and information on the processes involved in modernization of the production process automatic control system of the plant is presented.

This article deals with the experience of operating the Votkinsk HPP, one of the largest hydroelectric power plants in the Volga-Kama cascade. The engineering decisions and ideas used to solve the problems confronted by hydroelectric power engineers are examined.

The strength and deformability of brittle polycristalline materials (rock, cement, gypsum) in triaxial stress-strain state are analyzed. It is shown that the strength of such materials increases. The subcritical and postcritical stress-strain curves for polycristalline materials are presented.

An approach to numerical simulation of flooding of residential areas is proposed. It involves modeling of all buildings and other structures in the flood plain, which can automatically be done with the help of modern software. Two-dimensional Saint-Venant equations on unstructured adaptive meshes are used without the need to introduce additional parameters and coefficients. The main advantage of the method is high accuracy and realism of modeling and graphical representation of flood waves and dam-break waves on residential areas. This method is validated against experimental data and real objects.

Aspects of designing scrolls of hydraulic machines based on the equations of potential flow induced by a vortex sink cylinder of finite length and uniform strength located on an impermeable cylinder of infinite length are discussed. The cross-section of such scrolls is drop-shaped, which is substantially different from the shapes currently used. Their dimensions are strongly dependent on the cone angles of the scroll and the flow direction at the leading edges of the guide vanes. The dimensions of the scroll do not depend on the output of the hydraulic machine and are less than those of scrolls of circular cross-section.

Results of calculations and test firing of non-design 3BR grade coal from the Bol’shesyrskii deposit instead of 2BR Borodino coal in a BKZ-160-1,4-5 boiler with mill-fans are described. The feasibility of using Bol’shesyrskii coal in BKZ-160-1,4-5 boilers for mandatory blast of furnace screens by four water cleaning systems is demonstrated.

The life of a high-pressure convection superheater with damaged coils and a low-pressure superheater of the second stage of a TGMP-314 boiler is analyzed numerically. The dependence of the temperatures of steam, metal, and flue gas at the outlet of the coil banks on the number of plugged coils is established. It is shown that plugging gives rise to sparse banks with overheated coils, high-temperature gas plume that initiates overheating of the downstream tube banks, nonuniform softening of the metal, and reduction of the operational reliability of the superheaters.

Measures to ensure the reliability of turbine foundations are addressed. Requirements to be met during design, construction, and operation to prolong the life of turbogenerator foundations are considered. Regulations on obligations, terms, and scope of inspections of foundations to prevent emergencies are cited.

Results of designing, at the OJSC “Power Machines,” a full-scale bench for testing a broad range of auxiliary equipment (AE) are presented. The importance of full-scale tests for improving design methods for AE is showed. The test results for some AE are interpreted graphically. It is concluded that this AE meets the consumer requirements.

It is shown that currently-accepted assumptions for calculating heat exchange for stranded and shaped wires of overhead lines are unsubstantiated and result in unjustified errors in the analysis of heating of wires. Using known provisions of the theory of heat exchange, as well as generalized data on heating of wires and pipes obtained by various authors in different countries at various times, it is possible to suggest universal recommendations on determining heat exchange, and consequently also temperatures of round, stranded, and shaped wires for both longitudinal and transverse air flow by both weak and strong winds.

The basic stages in the development and introduction of automatic systems of continuous monitoring and measurement of discharges of polluting substances into the atmosphere from thermal electric power stations are presented. Stages of the pre-design and design steps are considered in detail and recommendations for assembly and operations of the measuring instruments which are incorporated into the system are given. The recommendations are a part of a unified regulatory guidance document for use in the creation and operation of an automatic system of continuous monitoring and measurement of discharges of polluting substances from thermal electric power stations that has now been developed at the National Research University “Moscow Power Engineering Institute”.

A method is presented for determining parameters of an equivalent circuit of an induction motor with a squirrel-cage rotor according to data from digital recording of instantaneous values of currents and stator voltage and slip, obtained from usual operational modes of start-up and work under load. Parameters of the stator, magnetization branch, and core loss contour are determined by data of measurements from two or more modes of load conditions with various slips, and the dependence of current displacement coefficients for active and inductive rotor resistances on the slip, from startup mode. Parameters of an equivalent circuit are derived from the iterative-method solution of equations containing the design and measured mode parameters. Examples confirming the efficacy of the developed method are presented.