Study of changes in the coefficient of hydraulic friction of materials of pressure pipes at different temperatures

Author(s):  
В.А. Орлов ◽  
С.П. Зоткин

Снижение затрат электроэнергии на механическую транспортировку воды по напорным трубопроводам за счет уменьшения гидравлического сопротивления внутренних стенок труб носит актуальный характер. Это обстоятельство предопределяет необходимость проведения соответствующих гидравлических испытаний альтернативных материалов, которые могут быть использованы при проектировании и строительстве трубопроводных систем. Целью исследований является выявление характера изменения величины гидравлического трения в зависимости от температурных условий транспортируемой воды и окружающей среды в определенных диапазонах с последующей возможностью управления процессом транспортировки при минимуме затрат на электроэнергию. Достижение поставленных целей осуществляется путем опытного и расчетно-аналитического подходов к определению динамики изменения гидравлических показателей трубопроводов из различных материалов. Представлен комплексный анализ экспериментальных и расчетных данных, полученных с помощью запатентованных автоматизированных комплексов, по определению коэффициентов гидравлического трения для полиэтиленовой трубы и трубы из непластифицированного поливинилхлорида и динамики изменения этих коэффициентов в зависимости от температуры транспортируемых вод и температурных условий прокладки трубопроводов. Reducing the cost of electricity for the mechanical transportation of water through pressure pipelines by reducing the hydraulic resistance of the inner walls of the pipes is of current importance. This circumstance predetermines the need for appropriate hydraulic testing of alternative materials that can be used in the design and construction of pipeline systems. The aim of the study is to identify the nature of the change in the value of hydraulic friction depending on the temperature conditions of the transported water and the environment in certain ranges, with the subsequent possible control of the transportation process with a minimum of energy costs. The set goals are achieved by experimental computational and analytical approaches to determining the dynamics of changes in the hydraulic parameters of pipelines made of various materials. A comprehensive analysis of the experimental and calculated data obtained using patented automated systems for determining the coefficients of hydraulic friction for a polyethylene pipe and a pipe made of unplasticized polyvinylchloride, and the dynamics of changes in these coefficients depending on the temperature of the transported water and the temperature conditions of pipeline laying is presented.

2016 ◽  
Vol 3 (3) ◽  
pp. 150679 ◽  
Author(s):  
Anthony A. Robson ◽  
Lewis G. Halsey ◽  
Laurent Chauvaud

The effects of unnatural disturbances on the behaviour and energetics of animals are an important issue for conservation and commercial animal production. Biologging enables estimation of the energy costs of these disturbances, but not specifically the effect these costs have on growth; a key outcome measure for animal farming enterprises. We looked at how natural and anthropogenically induced activity and energy expenditure of king scallops Pecten maximus varies with temperature. These data were then used to model growth time of king scallops reared in an aquaculture facility under different temperatures and anthropogenic disturbance levels. The scallops exhibited a typical total metabolic rate (MR)–temperature curve, with a peak reached at a middling temperature. The percentage of their total MR associated with spinning and swimming, behavioural responses to disturbance, was considerable. Interestingly, as temperature increased, the activity MR associated with a given level of activity decreased; a hitherto unreported relationship in any species. The model results suggest there is a trade-off in the ambient temperature that should be set by hatcheries between the optimal for scallop growth if completely undisturbed versus mitigating against the energy costs elicited by anthropogenic disturbance. Furthermore, the model indicates that this trade-off is affected by scallop size. Aquaculture facilities typically have controls to limit the impact of human activities, yet the present data indicate that hatcheries may be advised to consider whether more controls could further decrease extraneous scallop behaviours, resulting in enhanced scallop yields and improved financial margins.


Author(s):  
Viktoriya Yu. Ukhanova

In the pig breeding, a large share of the production cost is accounted for by the cost of electricity and heat. Reducing energy costs is one of the important tasks of the industry. It is important to identify and study modern technologies and equipment for pig farming due to the constant increase in electricity tariffs, significant energy costs for creating and maintaining a microclimate. (Research purpose) The research purpose is in an analysis of modern available technologies and equipment for agricultural production, including pig farming, allowing to reduce the cost of production. (Materials and methods) Authors used a method for determining the standard indicators of energy consumption of energy resources in the pig industry, based on the calculation and analytical method. The article presents an analyze of automated microclimate management systems in pig breeding complexes, taking into account the individual characteristics of farms produced by OWEN. (Results and discussion) Automated microclimate management systems can improve the productivity of pig farms; reduce the cost of electrical and thermal energy, reduce the number of diseases of animal from hypothermia, high humidity or temperature in the room, feed consumption; monitor the chemical composition of the air. The article considers three options for creating a microclimate in rooms with animals, taking into account the individual characteristics of enterprises. (Conclusions) The profitability of pig production depend on the level of technical equipment of farms, automation, and the use of energy-saving technologies and equipment. The use of innovations in agricultural production makes it possible to increase labor productivity up to three times, and savings due to reduced feed costs can reach several million rubles a year.


2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Ayari Takamura ◽  
Daisuke Watanabe ◽  
Rintaro Shimada ◽  
Takeaki Ozawa

Abstract Blood, as a cardinal biological system, is a challenging target for biochemical characterization because of sample complexity and a lack of analytical approaches. To reveal and evaluate aging process of blood compositions is an unexplored issue in forensic analysis, which is useful to elucidate the details of a crime. Here we demonstrate a spectral deconvolution model of near-infrared Raman spectra of bloodstain to comprehensively describe the aging process based on the chemical mechanism, particularly the kinetics. The bloodstain spectra monitored over several months at different temperatures are decomposed into significant spectral components by multivariate calculation. The kinetic schemes of the spectral components are explored and subsequently incorporated into the developed algorithm for the optimal spectral resolution. Consequently, the index of bloodstain aging is proposed, which can be used under different experimental conditions. This work provides a novel perspective on the chemical mechanisms in bloodstain aging and facilitates forensic applications.


Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1827
Author(s):  
Mengyao Li ◽  
Yu Zhang ◽  
Ting Zhang ◽  
Yong Zuo ◽  
Ke Xiao ◽  
...  

The cost-effective conversion of low-grade heat into electricity using thermoelectric devices requires developing alternative materials and material processing technologies able to reduce the currently high device manufacturing costs. In this direction, thermoelectric materials that do not rely on rare or toxic elements such as tellurium or lead need to be produced using high-throughput technologies not involving high temperatures and long processes. Bi2Se3 is an obvious possible Te-free alternative to Bi2Te3 for ambient temperature thermoelectric applications, but its performance is still low for practical applications, and additional efforts toward finding proper dopants are required. Here, we report a scalable method to produce Bi2Se3 nanosheets at low synthesis temperatures. We studied the influence of different dopants on the thermoelectric properties of this material. Among the elements tested, we demonstrated that Sn doping resulted in the best performance. Sn incorporation resulted in a significant improvement to the Bi2Se3 Seebeck coefficient and a reduction in the thermal conductivity in the direction of the hot-press axis, resulting in an overall 60% improvement in the thermoelectric figure of merit of Bi2Se3.


Author(s):  
А.О. РЕНЗЯЕВ ◽  
О.П. РЕНЗЯЕВ ◽  
С.Н. КРАВЧЕНКО ◽  
Р.В. КРЮК

Исследованы прочностные и физико-механические свойства оболочки рапса с точки зрения ее разрушения и удаления. Установлено, что наиболее рациональным является двухстадийный способ обрушивания: 1-я стадия – на вальцовых мельницах, 2-я – на центробежной обрушивающей машине. Определены параметры центробежной обрушивающей машины для обеспечения минимальной необходимой линейной скорости 10,81 м/с: угол наклона отбойной пластины (90 ± 2)°, частота вращения барабана (2400 ± 150) об/мин. Установлено, что правильно подобранные условия и угол, под которым происходит удар, позволяют значительно снизить количество не до конца обрушенного семени и содержание расколотого ядра. При этом при свободном ударе об отбойную пластину под углом, отличным от 88–91°, или подаче недостаточно равномерного потока семян значительно увеличивается содержание необрушенных семян. На разрушение 1 кг семян необходимо затратить 58,45 Дж. Таким образом, по расчетным данным, для семян рапса диаметром 1,5 мм частота вращения барабана должна находиться в диапазоне от 2221 до 2565 об/мин при ударе семени под углом 90°. Диаметр семян рапса, выращиваемого в Сибирском регионе, составляет от 0,8 до 1,8 мм. Установлено, что подсушивание семян рапса в течение 30–40 с при температуре 100°С позволяет увеличить эффективность разрушения оболочки до полного ее отделения от ядра рапса. Представленные результаты позволяют повысить качество очистки семян рапса от оболочки и улучшить качественные характеристики получаемого масла, облегчить последующие технологические процессы получения пищевого масла, снизить затраты на рафинацию и дезодорацию на 2%. The strength and physico-mechanical properties of the shell of rapeseed in terms of its destruction and removal are investigated. It is established that the most rational is a two-stage method of seed hulling: the 1st stage – on roller mills, the 2nd – on a centrifugal hulling machine. The parameters of the centrifugal hulling machine to provide the minimum required linear speed of 10,81 m/s are defined: the angle of inclination of the turnback plate (90 ± 2)°, the rotational speed of drum (2400 ± 150) RPM. It is established that the correctly selected conditions and the angle at which the impact occurs, can significantly reduce the amount is not completely hulling seed and the substance of the split nucleus. At the same time, with a free impact on the turnback plate at an angle different from 88–91°, or the supply of an insufficiently uniform flow of seeds, the content is not completely hulling seed increases significantly. On hulling of 1 kg of seeds it is necessary to spend 58,45 J. Thus, according to the calculated data, for rape seeds with a diameter of 1,5 mm, the rotational speed of drum should be in the range from 2221 to 2565 RPM when the seed is struck at an angle of 90°. The diameter of rapeseed grown in the Siberian region ranges from 0,8 to 1,8 mm. It was found that drying of rapeseed for 30–40 s at a temperature of 100°C, can increase the efficiency of destruction of the shell to its complete separation from the core of rapeseed. The presented results make it possible to improve the quality of cleaning of rape seeds from the shell and improve the quality characteristics of the obtained oil, facilitate the subsequent technological processes of obtaining edible oil, reduce the cost of refining and deodorization by 2%.


2020 ◽  
Vol 50 (4) ◽  
Author(s):  
Marcos Kovaleski ◽  
João Leodato Nunes Maciel ◽  
Gustavo Bilibio dos Santos ◽  
Alieze Nascimento da Silva ◽  
Carolina Cardoso Deuner

ABSTRACT: Wheat blast is known for developing itself more intensely under relatively high temperature conditions but many aspects related to its epidemiology remain unknown. The objective of this research was to evaluate the sporulative capacity of Pyricularia oryzae Triticum (Pot), the causal agent of wheat blast, in tissues of wheat plants under different temperatures degrees. Wheat plants of the cultivar Anahuac 75, susceptible to blast, were inoculated in the stage of flowering with conidial suspensions (105 conidia/mL) of the Pot isolates Py 12.1.209 and Py 12.1.132. Seven days after the inoculation, plants were cut in the following segments: leaves, stems and rachis (with blast severity ranging from 40 to 60%). Groups of each one of the three plant segments with the lesions were disposed in Petri-dish moist chambers, that were submitted to six different temperature treatments (18, 21, 24, 27, 30 and 33 °C). The most appropriate model that related the conidia production with temperature was identified in the evaluations conducted with stems. The established equations allowed identifying that the highest production of conidia of Pot occurs between 24 and 27 °C.


Author(s):  
Aleksey Sklyar ◽  
Margarita Postnova

Currently, the modern poultry farms are located in regions with different climatic conditions. Thus, the component of the electric power being the base for combined heating and ventilating systems, lighting, and local heating of poultry farms, is great in power engineering on the territory of the Russian Federation. The analysis of energy costs of poultry farms showed that of the estimated options for reducing the cost of electricity for poultry farms, one of the most effective can be an alternative source such as the generation of own electricity. Naturally, for biological production with a continuous technological cycle (poultry farming, for example), seems to be replace about 45-55 % of the needs of the factory and serve as a reserve for the rest, but not cover all 100 % of needs.


2019 ◽  
Vol 294 ◽  
pp. 01001 ◽  
Author(s):  
Serhii Arpul ◽  
Viktor Artemchuk ◽  
Mykola Babyak ◽  
Viacheslav Vasilyev ◽  
Hennadii Hetman ◽  
...  

The paper considers the issues of reducing the energy intensity of transportation at opencast mining enterprises, the relevance of which has now increased due to the rise in the cost of fuel and energy resources. It presents the study results concerning the cost structure of the electricity consumed by electric mine transport, which form the basis for the development of technical and operational measures to reduce the energy intensity of the transportation process. It is shown that the work to reduce the electricity consumption for mined rock transportation should be aimed at: Reduction of losses in the power circuits of the traction rolling stock due to the use of more advanced electric rolling stock and regulation of the degree of utilization of the installed traction power; Introduction of new contact materials for electrical circuits with the lowest possible resistivity, including for current collector plates; Introduction of measures to reduce energy consumption for power supply of auxiliary circuits; Development and implementation of rational train control techniques. The introduction of energy-saving measures should include the development and application of effective methods for calculating individual norms of energy consumption and incentives for energy saving of the employees involved in the organization of the transportation process.


Author(s):  
Sathish K. Gurupatham ◽  
Erhan Ilksoy ◽  
Nick Jacob ◽  
Kevin Van Der Horn ◽  
Fahad Fahad

Novel technologies have always been an indispensable part of the scientific enterprise and a catalyst for new discoveries. The invisible radiation patterns of objects are converted into visible images called thermograms or thermal images. Thermal images can be utilized to estimate the ripeness of some fruits which do not change their color from yellow to green when they are ripe. Thermal imaging techniques are very helpful since color and fluorescent analytical approaches cannot be applied to these fruits. In this work, it is shown that different ripeness levels of avocado (Hall type) using a non-destructive method called thermal imaging, in two dimensional spaces. The work is based on the fact that fruits have different specific heat capacities at different temperatures, thus making their thermal images clear indicators of ripeness.


2019 ◽  
Vol 17 (3) ◽  
pp. 402-408
Author(s):  
Md Ismail Hossain ◽  
Fatema Hoque Shikha ◽  
Nurun Naher

For value addition, only developing different products from fish muscle /mince is not enough, as maintenance of proper storage condition to keep the sensory attributes in acceptable range and marketing of the developed products very important. Therefore, the study was carried out to observe the changes in sensory attributes of fish condiment prepared from Thai pangus mince, stored at different temperatures. In the development of product and different analysis standard procedures were followed with some modification in the processes. In this study, a detailed survey on consumers’ preference to fish condiment was done at Kamal-Ranjit Market of Bangladesh Agricultural University (BAU), Kewatkhali, Mymensingh town and Faculty of Fisheries (BAU). This study revealed that the sensory attributes of fish condiment decrease throughout the storage period irrespective of storage temperatures (room temperature, 28°C to 32°C; refrigeration temperature, 5°C to 8°C and frozen temperature, -18°C to -20°C). At low temperatures, this product may remain in acceptable condition for more than 120 days. The consumers’ preference study showed that most of the respondents liked fish condiment and also they showed their interest to buy from shop and shop owners showed interest to sell this product. The average price offered by the consumers for the fish condiment was 18.52 taka and by the shopkeepers, 19.51 taka for 10g of condiment in each pack; which were much higher than the production cost. The cost profit analysis showed that the margin of profit for the fish condiment was 35.14%. J Bangladesh Agril Univ 17(3): 402–408, 2019


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