Consideration of reducing purchased power using photovoltaic excess power by thermal radiative cooling/heating system

Here, we address the turbulent dynamics of the gravitational instability in accretion disks, retaining both radiative cooling and irradiation. Due to radiative cooling, the disk is unstable for all values of the Toomre parameter, and an accurate estimate of the maximum growth rate is derived analytically. A detailed study of the turbulent spectra shows a rapid decay with an azimuthal wave number stronger than ky−3, whereas the spectrum is more broad in the radial direction and shows a scaling in the range kx−3 to kx−2. The radial component of the radial velocity profile consists of a superposition of shocks of different heights, and is similar to that found in Burgers’ turbulence. Assuming saturation occurs through nonlinear wave steepening leading to shock formation, we developed a mixing-length model in which the typical length scale is related to the average radial distance between shocks. Furthermore, since the numerical simulations show that linear drive is necessary in order to sustain turbulence, we used the growth rate of the most unstable mode to estimate the typical timescale. The mixing-length model that was obtained agrees well with numerical simulations. The model gives an analytic expression for the turbulent viscosity as a function of the Toomre parameter and cooling time. It predicts that relevant values of α = 10−3 can be obtained in disks that have a Toomre parameter as high as Q ≈ 10.

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Innovative electrotechnological systems to provide the temperature modes of technological pipelines

Power and Autonomous equipment ◽

10.32464/2618-8716-2019-2-1-29-39 ◽

2019 ◽

Vol 2 (1) ◽

pp. 29-39 ◽

Cited By ~ 1

Author(s):

S. G. Konesev ◽

P. A. Khlyupin

Keyword(s):

Induction Heating ◽

Thermal Exposure ◽

Heating System ◽

The Arctic ◽

Process Conditions ◽

Heating Systems ◽

Fluid Properties ◽

Low Efficiency ◽

Extreme North ◽

Induction Heating System

Introduction: the systems of thermal effects on thermo-dependent, viscous and highly viscous liquids under conditions of the Arctic and the Extreme North are considered. Low efficiency and danger of heating systems based on burned hydrocarbons, heated liquids and steam are shown. Electrothermal heating systems used to maintain thermo-dependent fluids in a fluid state are considered. The evaluation of the effectiveness of the application of the most common electrothermal system — heating cables (tapes). The most effective electrothermal system based on induction technologies has been determined. Materials and methods: considered methods of thermal exposure to maintain the fluid properties of thermo-dependent fluids at low extreme temperatures. Results: presents an induction heating system and options for its implementation in the Extreme North and the Arctic. Conclusions: induction heating system to minimize loss of product quality, improve the system performance under changing process conditions, eliminate fire product, to reduce the influence of the human factor.

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Analysis of energy efficiency of polder of pumping stations in a Slavsk district of the Kaliningrad region

Melioration and Water Management ◽

10.32962/0235-2524-2020-2-15-20 ◽

2020 ◽

pp. 15-20

Author(s):

Yuriy Spirin ◽

Vladimir Puntusov

Keyword(s):

Energy Efficiency ◽

Agricultural Land ◽

Statistical Processing ◽

Drainage Rate ◽

Pumping Stations ◽

Kaliningrad Region ◽

Pumping Equipment ◽

Excess Power ◽

The Cost ◽

Domestic Power

In the Kaliningrad region there are about 70 % of all polder lands in Russia. On these lands with high potential fertility, it is advisable to intensive agriculture. The area for the average moisture year is an area with excessive moisture, which indicates the need to maintain the rate of drainage on agricultural land. Many different factors play a role in ensuring the drainage rate, one of which is pumping stations and pumping equipment installed on them. An important parameter in the use of pump-power equipment is energy consumption, since in this industry it is a considerable expense item. Improving the energy efficiency of pumping stations on polders is a pressing issue today. At the majority of polder pumping stations, domestic power pumping equipment is installed with excess power and head of 4–8 meters, and a new one is selected based on the maximum possible head in a given place. In the Kaliningrad region, the energy efficiency of polder pumping equipment has never been analyzed. In this paper, a statistical processing of the geodesic pressure of water at the polder pumping stations of the Slavsk region for 2000–2002 was carried out. On the basis of these data and data on the hydraulic characteristics of pressure pipelines, the calculated water pressures were determined for the rational selection of pumping equipment. The calculation of the economic efficiency of pumps with optimal power compared with pumps of excess capacity. The results of the study can serve as a justification for the transition to the pumping equipment with less power and pressure, which will lead to a decrease in the cost of money for electricity.

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