scholarly journals Improving the reliability of cable lines operation in hot climates

2020 ◽  
Vol 216 ◽  
pp. 01151
Author(s):  
Daniyar Bakhtiyarovich Madrakhimov ◽  
Vera Pavlovna Ivanova ◽  
Victoria Vyacheslavovna Tsypkina
Keyword(s):  
Solar Radiation ◽  
Climatic Factors ◽  
Climate Conditions ◽  
Term Operation ◽  
Asian Region ◽  
Hot Climate ◽  
Central Asian ◽  
Cable Lines ◽  
The Impact

Reliability of cable lines in hot climate is determined by the climatic characteristics of cables and wires, which include: long-term and short-term heat resistance, cold resistance, moisture resistance, resistance to cyclic exposure to temperatures and solar radiation, ozone resistance, etc. This article considers the main impacts of environmental factors: high temperatures, solar radiation, which, as practice shows, lead to irreversible deterioration of the electrical and mechanical properties of cable products. The result of climatic impacts in the Central Asian region, in hot climate conditions, is the aging of both insulation and protective coverings, which leads to irreversible change in the mechanical and electrical properties of the used polymers due to the loss of elasticity of the extruded material and its subsequent cracking, turning into cracks. The assessment of the possibility of long-term operation of the used polymer was carried out according to the polyethylene oxidation period, which determines the time of natural preservation of various types of cables during the period of their operation. The research was carried out on samples of cables stored under a canopy in wooden boxes, protected from sunlight and precipitation, by measuring criterion parameters with strict compliance with the established norms. Thus, the proposed solution for increasing the reliability of cable lines consists of debugging the technological process of applying insulation and sheathing, in which the extrusion of the polymer mass is carried out by technique that minimizes the ingress of contamination. Review of the results showed that extrusion line improvement would provide possibility of increasing reliability in the operation of cable products under the impact of climatic factors of the Central Asian region due to the reduced aging of insulation.

Numerical Modelling of a District Scale Groundwater Heat Pump Operation: Case Study from Colchester, UK

2021 ◽  
Author(s):  
Taha Sezer ◽  
Abubakar Kawuwa Sani ◽  
Rao Martand Singh ◽  
David P. Boon
Keyword(s):  
Large Scale ◽  
District Level ◽  
Thermal Plume ◽  
Injection Wells ◽  
Term Operation ◽  
Heating And Cooling ◽  
Groundwater Heat Pump ◽  
The Impact

<p>Groundwater heat pumps (GWHP) are an environmentally friendly and highly efficient low carbon heating technology that can benefit from low-temperature groundwater sources lying in the shallow depths to provide heating and cooling to buildings. However, the utilisation of groundwater for heating and cooling, especially in large scale (district level), can create a thermal plume around injection wells. If a plume reaches the production well this may result in a decrease in the system performance or even failure in the long-term operation. This research aims to investigate the impact of GWHP usage in district-level heating by using a numerical approach and considering a GWHP system being constructed in Colchester, UK as a case study, which will be the largest GWHP system in the UK. Transient 3D simulations have been performed pre-construction to investigate the long-term effect of injecting water at 5°C, into a chalk bedrock aquifer. Modelling suggests a thermal plume develops but does not reach the production wells after 10 years of operation. The model result can be attributed to the low hydraulic gradient, assumed lack of interconnecting fractures, and large (>500m) spacing between the production and injection wells. Model validation may be possible after a period operational monitoring.</p>

scholarly journals Long-term trends in solar radiation and the associated climatic factors over China for 1961-2000

2005 ◽  
Vol 23 (7) ◽  
pp. 2425-2432 ◽  
Author(s):  
F. Liang ◽  
X. A. Xia
Keyword(s):  
Solar Radiation ◽  
Climatic Factors ◽  
Sunshine Duration ◽  
Cloud Amount ◽  
Atmospheric Composition ◽  
Abrupt Decrease ◽  
Radiative Processes ◽  
Aerosol Loading ◽  
Long Term Trends

Abstract. Long-term trends in downwelling solar irradiance and associated climatic factors over China are studied in the paper. Decreasing trends in global and direct radiation are observed over much of China. The largest decrease occurs in South and East China (east of about 100° E and south of about 40° N). The spatial pattern of observed trends in diffuse irradiance is complex and inhomogeneous. An intriguing aspect of trends in global and direct irradiance is the rather abrupt decrease in annual and seasonal mean values from 1978 onward. The decreasing trends in solar radiation in China did not persist into the 1990s. The spatial and temporal patterns of trends in sunshine duration are consistent with that of global and direct irradiance. A decreasing trend in rainy days is observed over much of China, which is in agreement with the secular trend in cloud amount. The fact that trends in cloud amount and solar radiation are quite similar suggests that the cloud amount is not the primary cause for the decrease in solar radiation. Visibility in the eastern part of China has deteriorated heavily as a result of the rapid increase in aerosol loading. The statistical analysis showed that atmospheric transmission under clear conditions decreased rapidly. These facts suggest that the rapid increase in aerosol loading should be one of the principle causes for the decrease in solar radiation. The observed diurnal temperature range decreases remarkably in China, which is closely related to the increase in aerosols. The effects of anthropogenic air pollutants on climate should be further studied and included in the simulation of climate and projection of climate scenario. Keywords. Atmospheric composition and structure (Aerosol and particles; General or miscellaneous) – Meteorology and atmospheric dynamics (Radiative processes)

scholarly journals Analysis of influence of climatic factors on selecting types of solar panels

2020 ◽  
Vol 2020 (2) ◽  
pp. 21-26
Author(s):  
Sergey Vladimirovich Golovko ◽  
Dmitry Anatolyevich Zadorkin
Keyword(s):  
Solar Cell ◽  
Solar Radiation ◽  
Cell Surface ◽  
Alternative Energy ◽  
Climatic Factors ◽  
Climatic Conditions ◽  
Solar Panels ◽  
Efficient Operation ◽  
The Impact ◽  
Solar Rays

The article outlines the problem of the influence of climatic factors on the efficiency of solar panels operation. Not long ago the idea of free electricity seemed incredible. However, the development of technologies rapidly progresses, and the alternative energy captures more and more supporters every day. The popularity of solar panels is growing quite rapidly, since photovoltaic converters are an efficient source of electricity. But for more efficient operation of solar cells it is necessary to create the specific conditions, taking into account the location of the unit. There have been considered the factors of more efficient operation of the photovoltaic converters: the hash climatic conditions and the intensity of solar radiation depending on the angle of reducing the impact of the solar rays onto the solar cell surface.

scholarly journals The impact of road maintenance and construction on roadside vegetation

2021 ◽  
Vol 11 (225) ◽  
Author(s):  
Alexander Sudnik ◽  
◽  
Irina Voznyachuk
Keyword(s):  
Climatic Factors ◽  
Road Maintenance ◽  
Sources Of Pollution ◽  
Mobile Sources ◽  
Roadside Vegetation ◽  
Long Term Monitoring ◽  
The Impact ◽  
Negative Factors ◽  
Term Monitoring

The article provides data on the results of long-term monitoring of the state of vegetation along the main highways of Belarus, caused by environmental pollution in roadside strips with deicing reagents based on sodium chloride in winter in combination with a set of other negative factors (exhaust gases from mobile sources of pollution, changes in environmental conditions, extreme manifestations of weather and climatic factors).

scholarly journals Merging ground-based sunshine duration observations with satellite cloud and aerosol retrievals to produce high-resolution long-term surface solar radiation over China

2021 ◽  
Vol 13 (3) ◽  
pp. 907-922
Author(s):  
Fei Feng ◽  
Kaicun Wang
Keyword(s):  
Standard Deviation ◽  
High Resolution ◽  
Solar Radiation ◽  
Spatial Resolution ◽  
Sunshine Duration ◽  
Ordinary Least Squares ◽  
Cloud Fraction ◽  
Surface Solar Radiation ◽  
The Impact

Abstract. Although great progress has been made in estimating surface solar radiation (Rs) from meteorological observations, satellite retrieval, and reanalysis, getting best-estimated long-term variations in Rs are sorely needed for climate studies. It has been shown that Rs data derived from sunshine duration (SunDu) can provide reliable long-term variability, but such data are available at sparsely distributed weather stations. Here, we merge SunDu-derived Rs with satellite-derived cloud fraction and aerosol optical depth (AOD) to generate high-spatial-resolution (0.1∘) Rs over China from 2000 to 2017. The geographically weighted regression (GWR) and ordinary least-squares regression (OLS) merging methods are compared, and GWR is found to perform better. Based on the SunDu-derived Rs from 97 meteorological observation stations, which are co-located with those that direct Rs measurement sites, the GWR incorporated with satellite cloud fraction and AOD data produces monthly Rs with R2=0.97 and standard deviation =11.14 W m−2, while GWR driven by only cloud fraction produces similar results with R2=0.97 and standard deviation =11.41 W m−2. This similarity is because SunDu-derived Rs has included the impact of aerosols. This finding can help to build long-term Rs variations based on cloud data, such as Advanced Very High Resolution Radiometer (AVHRR) cloud retrievals, especially before 2000, when satellite AOD retrievals are not unavailable. The merged Rs product at a spatial resolution of 0.1∘ in this study can be downloaded at https://doi.org/10.1594/PANGAEA.921847 (Feng and Wang, 2020).

scholarly journals Long-term observations of supraglacial streams on an Arctic glacier

2019 ◽  
Vol 65 (254) ◽  
pp. 900-911 ◽  
Author(s):  
Sarah L. St Germain ◽  
Brian J. Moorman
Keyword(s):  
Solar Radiation ◽  
Unmanned Aerial Vehicles ◽  
Aerial Imagery ◽  
Digital Elevation ◽  
Small Streams ◽  
Hydrological System ◽  
Arctic Glacier ◽  
The Impact ◽  
Stream Formation

AbstractSupraglacial streams are a significant part of the glacial hydrological system and important for understanding glacial hydrology and dynamics. Here we infer factors that influence the long-term development of perennial supraglacial streams, particularly in reference to canyon, incised and surface stream formation. Orthophotos and digital elevation models generated from high-resolution aerial imagery taken with unmanned aerial vehicles or piloted helicopters between 2010 and 2017 were used to compare seven streams on Fountain Glacier, Bylot Island, Canada over time. Results show canyon formation occurs from a combination of fluvial processes and the impact of solar radiation. The greater the discharge or slope, the faster the incision and higher the sinuosity. With greater sinuosity, the distance between the top of the valley banks increases, and cutoffs cause trapezoidal canyon-like valleys to form. Solar radiation causes the backward migration of the valley walls, further enhancing canyon area. Canyons are less likely to occur in areas of low discharge and slope. Less incised channels are also more likely to have water flow jumping the channel banks, changing the channel path. The presence of medial moraines and crevasses also increases rerouting of small streams. Lastly, windblown created snow-plugs may lead to stream diversion.

Influence of bending radius on longitudinal stresses in long operation pipelines

2020 ◽  
Vol 10 (3) ◽  
pp. 234-242
Author(s):  
Robert М. Askarov ◽  
◽  
Aydar К. Gumerov ◽  
Rinat M. Karimov ◽  
Khiramagomed Sh. Shamilov ◽  
...  
Keyword(s):  
Technical Condition ◽  
Regulatory Requirements ◽  
Bend Radius ◽  
Term Operation ◽  
Mandatory Requirement ◽  
Bending Radius ◽  
New Construction ◽  
The Impact ◽  
Long Operation

Calculations of stress-strain state of pipelines are performed in accordance with the unified regulatory requirements, which do not take into account facilities operation. Thus, the limitation of minimal allowable bend radius with the value of 1000 pipe diameters (1000D) can be considered justified in relation to a new construction project, but the problem is that it is applied to all pipelines independently of its service life. At the same time the modern smart pigging technologies allow for obtaining precise data on bend radius of operated pipelines, and the diagnostics results indicate, that mandatory requirement for minimal value of 1000D frequently contradicts the actual technical condition of researched objects. The authors performed the analysis of standard formula for calculation of longitudinal stresses, considered the impact on the calculated value of its separate constituents: values of pressure, temperature difference and bend radius. The conclusion is made about the necessity for reassessment of the current regulations for scientific justification of acceptable values of pipeline longitudinal stresses. It is established, that the primary factor, which is responsible for forming the value of longitudinal stresses of the pipelines during long-term operation is the bend radius.

Terrestrial Solar Radiation

2017 ◽  
pp. 191-293
Keyword(s):  
Solar Radiation ◽  
Horizontal Plane ◽  
Cloud Cover ◽  
Weather Conditions ◽  
Clear Sky ◽  
Solar Tracking ◽  
Sky Conditions ◽  
The Impact ◽  
Estimation Models

After shading a light on the extraterrestrial solar radiation in the chapter 3 it is important to evaluate the global terrestrial solar radiation and its components. The information on terrestrial solar radiation is required in several different forms depending on the kinds of calculations and kind of application that are to be done. Of course, terrestrial solar radiation on the horizontal plane depends on the different weather conditions such as cloud cover, relative humidity, and ambient temperature. Therefore, the impact of the atmosphere on solar radiation should be considered. One of the most important points of terrestrial solar radiation evaluation is its determination during clear sky conditions. Therefore, in this chapter, the equations that determine the air mass basing on available theories are given and the clear sky conditions are introduced with shading a light on the previous work in identifying clear sky conditions. Taking into consideration that, clear sky solar radiation estimation is of great importance for solar tracking, a detailed review of main available models is given in this chapter. As daily, monthly, seasonally, biannually and yearly mean daily solar radiations are required information for designing and installing long term tracking systems, different available methods are commented regarding their applicability for the estimation of solar radiation information in the desired format from the data that are available. An important accent is paid also on the assessment and comparison of monthly mean daily solar radiation estimation models.

The Global Long-Term Agricultural Experiment Network

2020 ◽  
Author(s):  
Carolina Cardoso Lisboa ◽  
Jonathan Storkey ◽  
Carlos Eduardo Pellegrino Cerri ◽  
Christian Thierfelder ◽  
Juan Andres Quincke ◽  
...  
Keyword(s):  
Food Production ◽  
Deep Understanding ◽  
Agricultural Science ◽  
Modeling Tools ◽  
Soil C ◽  
Climate Conditions ◽  
C Stocks ◽  
Agricultural Experiment ◽  
The Impact

<p>Balancing food production with environmentally sustainable land management can have important climate change mitigation co-benefits. Recent reports, including the IPCC latest Special Report, launched at the COP 25 in December 2019, have highlighted the significant role of soil carbon (C) stocks in agricultural soils in achieving CO<sub>2</sub> zero emissons and contributing to CO<sub>2</sub> removal. However, to measure the soil C balance (C-gains and C-losses), a deep understanding of the processes governing the changes in soil C stocks in agricultural systems is required as well as knowledge on the impact of management over long and short time scales under distinct climate conditions. An understanding of the mechanisms underpinning these processes depends on robust evidence-based datasets that can be applied to several different models to model soil C-dynamics over time and make predictions upon future scenarios.  The datasets from long-term experiments (LTEs) can be extremely valuable to facilitate the evaluation of alternative food production systems impact/effect on soil health, as such soil C stocks. Employing modeling tools to analyse these data, would lead to better evaluation of land use and management practices and its environmental impacts around the globe. With the aim of supporting the agricultural science community in meeting this and related objetives, the Global Long-Term Agricultural Experiment Network (GLTEN) was launched in October 2019. The main goal of the network is to assemble and harmonize, following FAIR Data Principle (findable, accessible, interoperable and reusable), metadata from LTEs through the online GLTEN-Metadata Portal (https://glten.org/). This initial scientific investigation of the data shared between the experiments focusses on soil C data analyzed using free available tools to exploit and compare the trade-offs between several agricultural practices and C-offset given the distinct soil type and climate conditions. With the support of the GLTEN-members, we will start these joint analyses applying the Carbon Benefits Tools (https://banr.nrel.colostate.edu/CBP/) and the RothC Model (https://www.rothamsted.ac.uk/rothamsted-carbon-model-rothc). The progress of this collaborative work relies on the commitment and expertise of the GLTEN-members and we expect that the outcome from this investigation will support the knowledge refining and advancing the development of existing modeling tools. Furthermore, we will demonstrate the potential for the GLTEN to provide a platform that supports and facilitates collaborative research among the community.</p>

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