Том 51, № 2 (2017)

The evaluation of ecosystem services is a method of estimating the value of the natural capital of a defined territory. This article examined the approaches to an evaluation of ecosystem services as a method of an ecological-economic evaluation of the efficiency of hydropower projects.

The applicability of the provisions of SNiP 2.06.04–82* [1] regarding the determination of ice loads on offshore ice-resistant structures is examined. Experience with large-scale measurements of ice impacts on wide and narrow structures is presented. The general SNiP design parameters are analyzed on the basis of known field measurements: parameters to determine ice durability under compression, ice pressure, and determination of ice load from an ice floe on vertical structures. Shortcomings of the standards document are analyzed, and directions for its improvement are specified.

A new method is proposed for determining equivalent sand roughness from data for measurements of the hydraulic resistance of an annular channel. The channel is formed by a smooth pipe into which a rod with surface roughness is inserted coaxially. The equivalent sand roughness is also determined for this roughness and is applied in calculations for various hydraulic channels. Results confirming the feasibility of this method are presented.

Recommendations are given for determining the maximum density of the investigated soil when calculating their compaction coefficient in the dam body.

The condition of the hydraulic turbines with service life (30 years) expired long ago still operating at the Verkhnyaya Tuloma HPP is described. Parameters of the new hydraulic turbine that provides more efficient use of water flow at the HPP and improves the reliability of equipment are proposed.

Theoretical characteristics of the flow in scrolls of hydraulic turbines whose cross-sectional dimensions and shapes are determined using the equations of the potential flow induced by a vortex sink cylinder of finite length located on an impermeable cylinder of infinite length in an ideal fluid are calculated. The theoretical distributions of the components of the velocity and the directions of its horizontal and vertical projections (vertical turbine) are determined and plotted. They are favorable for hydraulic turbines and are in good agreement with the values set at the stator inlet, which confirms the effectiveness of the new approach to studying potential flows whose velocity potential cannot be expressed analytically.

The development of algorithms for the prediction of technological operating failure of nuclear power plant equipment based on stochastic extrapolation of the values of technical parameters is discussed. The algorithms are tested on real archived data on the operation of the oil circulation system of the main circulating pumps in a power generating unit at a nuclear power plant.

Results of test firing of grade D coal from the reserve of JSC “Shubarkol’ Komir” in boilers of 225-MW units at the Cherepetskaya State regional electric power plant are discussed. The technical, economic, and ecological characteristics of the boilers are estimated.

A method of determining for braided and shaped conductors the perimeter and surface area used in calculations of the temperature of the conductors, admissible currents, sag, de-icing regimes, and other thermal calculations is presented and validated. It is shown that the existing practice of determining this area in the same manner as for round conductors of the same diameter cannot be recommended because it leads to inadmissibly large errors (about 40%), which strongly affects the accuracy of thermal calculations.

The strengths and shortcomings of mathematical models of Makkonen and Lozowski to estimate the parameters of ice formation on an overhead power line are analyzed. The models are compared with a model of monitoring the intensity of ice formation that is currently undergoing tests on the PJSC IDGC Yuga networks. A conclusion is drawn regarding the necessity of conducting additional comprehensive research.

An improved algorithm is described for phase comparison in differential protection leg currents to ensure stable operation in the conditions of measuring current transformers saturation. The operation of the algorithm is examined on the example of differential protection of a power transformer with group 11 winding connections.

Fundamentally new software and hardware systems for lower level automation in the safety monitoring and control systems of nuclear power plants are examined. More than a hundred software-hardware systems employing software and hardware from different manufacturers have been developed and introduced in this area. Design and functional solutions based on specific software-hardware systems are presented and comparative data on the apparatus and the use of the diversity principle are discussed.

Reasons are examined for failures of gas-insulated circuit breakers on lines with shunt reactors that provide a level of line compensation close to 100%. It is shown that using a TCSR as a linear reactor makes it possible to eliminate the reason leading to failure of the circuit breaker in line testing.