scholarly journals Performance improvement methods of hydroficated machine under refrigeration

2021 ◽  
Vol 2094 (4) ◽  
pp. 042087
Author(s):  
A S Kaverzina ◽  
A S Lunev ◽  
I V Karnaukhov ◽  
M D Pankiv ◽  
I V Andreychikov

Abstract In this paper, the problem of the influence of climatic conditions on the performance of a Hydraulic gear is considered. The importance of the work is due to the fact that the methods for solving the problem are proposed, namely, the use of preheating for a Hydraulic gear and an internal combustion engine under refrigeration. The use of hydrofected self-propelled vehicles in the northern regions in winter is considered. The factors determining the technical and economic indicators of hydrofected machines are revealed. The influence of negative temperature on the physical and mechanical properties of hydraulic equipment materials is also considered. Three main directions have been identified in which temperature affects the hydraulic drive. An experiment was conducted in which the dependence of the performance of the machine was revealed using a preheating device for the working fluid and without the device.

Author(s):  
M.V. Tsvetkov ◽  
A.A. Nikitin

Currently, 70 % of Russian localities with a population of 9 million people are not connected to the transport system of the country by paved roads, especially in the northern regions, where the ambient temperature in winter does not rise above -500C. Road transport accounts for the largest number of transported goods. One of the vehicles of this type is an all-terrain vehicle Trackol, designed to move on roads with a weak surface: on snow, swamp and soil cover of thawed taiga. The analysis of the vehicle Trackol operation has shown insufficient reliability of its transmission. Analysis of of using the vehicle Trackol showed insufficient reliability of its transmission. To improve the situation the mechanical transmission has been replaced with a hydraulic one, taking into account the main disadvantages associated with maintaining the cleanliness of the working fluid. A system for regulating the temperature of the working fluid in the hydraulic drive of an all-terrain vehicle has been developed. The design of the working fluid filter is proposed, allowing capturing not only dirt, but also moisture due to the use of polyvinylformal of the TPVF brand as the filter element material.


2020 ◽  
pp. 33-36
Author(s):  
Е.Л. Макарова ◽  
Л.А. Чистякова ◽  
О.В. Бакланова ◽  
Ю.В. Борцова

Приведены экспериментальные данные оценки по хозяйственно полезным признакам одиннадцати новых партенокарпических гетерозисных гибридов огурца в условиях весенне-летнего оборота Кировской области. Проблема возделывания теплолюбивых культур в северных регионах страны формирует цели селекционных исследований. Выращивание культуры огурца в Кировской области усугубляется неблагоприятными климатическими условиями второй световой зоны (короткая продолжительность вегетационного периода, низкие положительные температуры, заморозки в третьей декаде июля и в первой декаде августа). Цель научной работы – оценка и выявление перспективных партенокарпических гетерозисных гибридов огурца для выращивания в условиях необогреваемых теплиц в весенне-летнем обороте второй световой зоны. Исследования проводили в лаборатории северного овощеводства Кировской области во Всероссийском научно – исследовательском институте овощеводства – филиале ФГБНУ «Федеральный научный центр овощеводства» в условиях поликарбонатных необогреваемых грунтовых теплиц в течение 2018-2019 годах. В результате фенологических наблюдений и оценки биометрических показателей определены раннеспелость, скороспелость и товарность испытуемых партенокарпических гетерозисных гибридов огурца селекции Агрохолдинга «Поиск» и ВНИИО – филиала ФГБНУ «Федеральный научный центр овощеводства»: F1Авоська, F1 Атос, F1 Букет для мамы, F1Малахитовая шкатулка, F1 Мультифрут, F1 Новатор, F1Пилигрим, F1 Спринтер, F1 Реванш, F1 Тонус, F1Экспресс в сравнении с районированным гибридом огурца F1 Каролина. Определено сильное негативное влияние климатических условий второй световой зоны на продолжительность периода «всходы-плодоношение», который в среднем за годы исследований в зависимости от гибрида варьировал от 47 до 55 суток. Установлено, что для получения ранней продукции огурца в условиях поликарбонатных необогреваемых грунтовых теплиц Кировской области следует выращивать гетерозисные партенокарпические гибриды огурца F1Спринтер (3,6 кг/м2), F1 Авоська (2,1 кг/м2) и F1 Атос (2,5 кг/м2). Отмечены партенокарпические гибриды огурца F1 Спринтер и F1 Атос, которые имеют наиболее высокий выход товарной продукции 95,7 и 94,0%, соответственно. Выделен самый урожайный партенокарпический гибрид огурца F1 Новатор (16,1 кг/м2). В результате исследовательской работы рекомендовано выращивать в условиях необогреваемых теплиц весенне-летнего оборота Кировской области партенокарпические гибриды огурца F1 Новатор, F1 Спринтер, F1 Атос и F1 Авоська. The article presents the experimental data on the assessment of economically useful traits of eleven new parthenocarpic heterotic cucumber hybrids under the conditions of the spring-summer turnover of the Kirov region. The problem of cultivation of thermophilic crops, which arises in the northern regions of the country, is one of the stages of breeding research. The cultivation of cucumber in the Kirov region is aggravated by unfavorable climatic conditions of the second light zone (short duration of the growing season, low positive temperatures, frosts in the third decade of July and in the first decade of August). The purpose of the scientific work is to evaluate and identify promising parthenocarpic heterotic hybrids of cucumber for growing in unheated greenhouses in the spring-summer turnover of the second light zone. The research was carried out in the laboratory of northern vegetable growing of the Kirov region at the All-Russian Research Institute of Vegetable Growing - a branch of the Federal State Budgetary Scientific Institution Federal Scientific Vegetable Centre in the conditions of polycarbonate unheated ground greenhouses during 2018-2019. As a result of phenological observations and assessment of biometric indicators, the early maturity, early maturity and marketability of the tested parthenocarpic heterotic cucumber hybrids of the selection of Agroholding Poisk and ARRIVG – a branch of the Federal Scientific Vegetable Centre were determined: F1 Avoska, F1 Atos, F1 Buket dlya mamy, F1 Multifrut, F1 Novator, F1 Piligrim, F1Sprinter, F1 Revansh, F1 Tonus, F1 Express in comparison with the zoned hybrid of cucumber F1 Carolina. A strong negative influence of climatic conditions of the second light zone on the duration of the seedling-fruiting period was determined, which on average over the years of research, depending on the hybrid, varied from 47 to 55 days. It has been established that to obtain early production of cucumber in polycarbonate unheated ground greenhouses of the Kirov region, heterotic parthenocarpic cucumber hybrids F1 Sprinter (3.6 kg/m2), F1 Avoska (2.1 kg/m2) and F1 Atos (2.5 kg/m2). Parthenocarpic cucumber hybrids F1 Sprinter and F1 Atos were noted, which have the highest yield of marketable products, 95.7 and 94.0%, respectively. The most productive parthenocarpic cucumber hybrid F1Novator (16.1 kg/m2) has been identified. As a result of the research work, it was recommended to grow parthenocarpic cucumber hybrids F1Novator, F1 Sprinter, F1 Atos and F1 Avoska under conditions of unheated greenhouses of spring-summer turnover of the Kirov region.


2018 ◽  
Author(s):  
M. T. Nitsas ◽  
I. P. Koronaki ◽  
L. Prentza

The utilization of solar energy in thermal energy systems was and always be one of the most effective alternative to conventional energy resources. Energy efficiency is widely used as one of the most important parameters in order to evaluate and compare thermal systems including solar collectors. Nevertheless, the first law of thermodynamics is not solely capable of describing the quantitative and qualitative performance of such systems and thus exergy efficiency is used so as to introduce the systems’ quality. In this work, the performance of a flat plate solar collector using water based nanofluids of different nanoparticle types as a working fluid is analyzed theoretically under the climatic conditions in Greece based on the First and Second Law of Thermodynamics. A mathematical model is built and the model equations are solved iteratively in a MATLAB code. The energy and exergy efficiencies as well as the collector losses coefficient for various parameters such as the inlet temperature, the particles concentration and type are determined. Moreover, a dynamic model is built so as to determine the performance of a flat plate collector working with nanofluids and the useful energy that can be stored in a water tank. The exergy destruction and exergy leakage are determined for a typical day in summer during which high temperatures and solar intensity values are common for the Greek climate.


Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 68
Author(s):  
Arkadiusz M. Tomczyk ◽  
Ewa Bednorz ◽  
Katarzyna Szyga-Pluta

The primary objective of the paper was to characterize the climatic conditions in the winter season in Poland in the years 1966/67–2019/20. The study was based on daily values of minimum (Tmin) and maximum air temperature (Tmax), and daily values of snow cover depth. The study showed an increase in both Tmin and Tmax in winter. The most intensive changes were recorded in north-eastern and northern regions. The coldest winters were recorded in the first half of the analyzed multiannual period, exceptionally cold being winters 1969/70 and 1984/85. The warmest winters occurred in the second half of the analyzed period and among seasons with the highest mean Tmax, particularly winters 2019/20 and 1989/90 stood out. In the study period, a decrease in snow cover depth statistically significant in the majority of stations in Poland was determined, as well as its variability both within the winter season and multiannual.


2021 ◽  
pp. 009524432110290
Author(s):  
Mariya L Davydova ◽  
Aytalina F Fedorova

This article represents the results of a study of changes in the properties of vulcanizates based on BNR-18 butadiene-nitrile rubber containing as stabilizers the experimental spatially hindered phenols Stafen, CO3, CO4, and industrial antioxidant 6PPD, after accelerated aging (100°C 96 h) and aging under full-scale exposure in extreme climatic conditions of the Republic of Sakha (Yakutia) during 2 years. In winter, the air temperature reached—48°C, in summer—+36.1°C. It is shown that the experimental sterically hindered phenols more effectively under natural exposure conditions. They are characterized by the most stability in terms of strength throughout the entire exposure period. Under conditions of accelerated aging, the vulcanizate containing the industrial antioxidant 6PPD is characterized by the greatest stability of physical and mechanical properties. According to the viscoelastic characteristics obtained in the dynamic loading mode, the contribution of the presented stabilizers in maintaining resistance to temperature and deformation effects compared with unstabilized rubber is confirmed.


2021 ◽  
Vol 3 (144) ◽  
pp. 116-121
Author(s):  
Nikita A. Pen’kov ◽  
◽  
Oleg A. Sidorkin ◽  
Sergey Yu. Zhachkin ◽  
Anatoliy I. Zavrazhnov ◽  
...  

One of the most common reasons for the failure of hydraulic drive systems for agricultural machinery is the working fluid leak in the contact points of the rubbing surfaces of hydraulic blocks. The application of composite coatings based on chromium on the contacting surfaces allows you to restore the defect in the shape of the part caused by wear, as well as reduce the friction coefficient at the contact points, which positively affects the wear resistance of the part. (Research purpose) The research purpose is in developing technologies for restoring parts of agricultural machinery with predetermined operational properties. (Materials and methods) A servo valve, widely used in various hydraulic drive systems, was used as an experimental sample. Its working surface was restored with a composite coating applied by electroplating to increase the wear resistance of the servo valve. (Results and discussion) Authors conducted a series of direct measurements under the same conditions. The article presents the de-pendence of the microhardness on the parameters of the electrolysis mode and the thickness of the applied coating using the method of least squares. The nature of changes in microhardness and residual stresses was evaluated to determine the quality of the coatings. The article presents the dependences of these indicators on various control parameters (current density, temperature, tool pressure). The equations of the regression of the main qualitative and accuracy characteristics of the parts were deter-mined using the apparatus of the theory of experimental planning. (Conclusions) The article presents the method for predicting coatings of a given quality, taking into ac-count the influence of the current density and the temperature of the electrolyte during electrolysis on the nature of the precipitation obtained. The influence of the tool pressure on the depth of deformation of the formed layers was estimated. This approach allows us to evaluate the nature of the stress distribution in the formed coating and the quality of the restored parts.


2018 ◽  
Vol 14 (3) ◽  
pp. 59-72
Author(s):  
L. Migranova ◽  
M. Toksanbaeva

The Object of the Study. Human potential.The Subject of the Study. The level and dynamics of development of the human potential of the population of the RF subjects. The Purpose of the Study. Identifying differences in development of the human potential of the population of the RF subjects and opportunities for their reduction.The Main Provisions of the Article. Human potential and its development are considered article both as the purpose and the means of human progress reflecting extension of human opportunities including creative (resource) capabilities. Theoretical and instrumental interpretation of the main components of human potential based on its reproductive structure is analysed. The components include a demographic component, components of population health and education, and a sociocultural component. For estimation of human potential indicators for each of its component, as well as a methodology for both component-by-component and composite (aggregate of all components) calculations using the index method are proposed. The methodology is applied to all RF subjects using the Rosstat data for 2010 and 2015. On the basis of the obtained estimates the authors have identified the levels of human potential development in regions that enabling to range them by this level and analyze the direction of its changes in dynamics. Components have been found out a weak and strong impact on the composite estimates as well as specifics of this impact by groups of regions. It has been established that demographic and health components leave much to be desired, particularly in northern regions characterized by harsh natural climatic conditions of life in particular.In North Caucasus regions the problem of raising educational level of population has not lost its relevance. It is shown that despite the general growth in the level of human potential development in most subjects of the Russian Federation over the period in question it remains insufficient for implementing modernization processes in some regions.


Author(s):  
Harold Sun ◽  
Dave Hanna ◽  
Liangjun Hu ◽  
Eric Curtis ◽  
James Yi ◽  
...  

Heavy EGR required on diesel engines for future emission regulation compliance has posed a big challenge to conventional turbocharger technology for high efficiency and wide operation range. This study, as part of the U.S. Department of Energy sponsored research program, is focused on advanced turbocharger technologies that can improve turbocharger efficiency on customer driving cycles while extending the operation range significantly, compared to a production turbocharger. The production turbocharger for a medium-duty truck application was selected as a donor turbo. Design optimizations were focused on the compressor impeller and turbine wheel. On the compressor side, advanced impeller design with arbitrary surface can improve the efficiency and surge margin at low end while extending the flow capacity, while a so-called active casing treatment can provide additional operation range extension without compromising compressor efficiency. On the turbine side, mixed flow turbine technology was revisited with renewed interest due to its performance characteristics, i.e. high efficiency at low-speed ratio, relative to the base conventional radial flow turbine, which is relevant to heavy EGR operation for future diesel applications. The engine dynamometer test shows that the advanced turbocharger technology enables over 3% BSFC improvement at part-load as well as full-load condition, in addition to an increase in rated power. The performance improvement demonstrated on engine dynamometer seems to be more than what would typically be translated from the turbocharger flow bench data, indicating that mixed flow turbine may provide additional performance benefits under pulsed exhaust flow on an internal combustion engine and in the low-speed ratio areas that are typically not covered by steady state flow bench tests.


2018 ◽  
Vol 212 ◽  
pp. 01013
Author(s):  
Vadim Balabanov ◽  
Victor Baryshok ◽  
Nikita Epishkin

The sharply continental climate of the Irkutsk region is characterized by wide temperature intervals throughout the year. The repeated cyclicity of freezing and thawing of building materials in the water-saturated state influences the change in technical characteristics and the durability of concrete products and structures. The concrete products’ features in such climatic conditions create the need for the production of concretes with improved indicators of physical and mechanical properties. The effect of modifying additives on the technological characteristics of sulfur concrete is established. The effect of all elements of sulfur concrete on its strength and frost resistance. The composition of sulfuric concrete is obtained, which meets all the requirements and also has high strength and increased frost resistance. Formulations with a certain ratio of structural sulfuric concrete mixtures were developed. As a result of the use of technical sulfur in the composition of concrete products, the problem of utilizing annually accumulating reserves of technical sulfur is partially solved. The strength properties of sulfuric concretes easily compete with high-quality brands of concrete, special types of concretes that have in their composition additives.


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