scholarly journals РОЗРАХУНКОВА МОДЕЛЬ ГІДРООБПРИСКУВАЛЬНОЇ УСТАНОВКИ ТУНЕЛЬНОГО ТИПУ

Author(s):  
О. М. Іванов ◽  
В. М. Арендаренко

Наведено результати теоретичних досліджень зіскладання розрахункової моделі гідрообприскувальноїустановки тунельного типу, призначеної для обприс-кування під високим тиском рослин у тунельній каме-рі. Дослідження проводились із залученням теоріїгідродинаміки та гідростатики для розрахунку скла-дних трубопроводів і багатокомпонентних гідравліч-них систем. За результатами розрахункових дослі-джень було складено аналітичні рівняння, що визна-чають величини гідравлічних параметрів у вузловихточках і встановлюють взаємозв’язок між основни-ми компонентами гідравлічної установки. The results of theoretical studies on the preparation of the computational model hydro spray tunnel designed for spraying high-pressure plants in the tunnel chamber. Studies were carried out using the theory of hydrodynamic and hydrostatic calculations for complex pipelines and multi-hydraulic systems. To achieve the objectives of the study were divided into components of hydraulic systems, each of which is a more simplified version of a complex pipeline. According to the results of computational studies were compiled analytical equations that determine the magnitude of hydraulic parameters at nodes and establish the relationship between the main components of the hydraulic system, and outlines the framework for the selection of a pressure pump for the amount of required pressure and flow.

2016 ◽  
Vol 68 (1) ◽  
pp. 45-51
Author(s):  
Guangying Ma ◽  
Shurong Ning ◽  
Yunlong Hu ◽  
jun Gao

Purpose – The aim of this study is to establish a dynamic model of the filtration ratio. For the problem that the measured value of the filtration ratio is far less than the theoretical value in the actual hydraulic filtering system, the paper aims to find the relationship between the filtration ratio and the parameters of the hydraulic systems, such as the contamination level and the dirt-holding quantity of the filter. Design/methodology/approach – The paper opted for the method of experimental analysis and simulation to determine the relationship between the filtration ratio and the parameters of the hydraulic system, and established a dynamic filtration ratio model. Findings – The paper provides a preliminary model of dynamic filtration ratio, and the model shows that the filtration ratio is exponentially related to the contamination level and the dirt-holding quantity. Different filters have different influence coefficients. The filtering capacity for a certain particle size and the contamination level control of the filter for different hydraulic systems can be judged according to the dynamic balance equation of hydraulic systems. Originality/value – The paper is useful in the selection of filters and in the precise control of the contamination level of the hydraulic system.


2021 ◽  
pp. 27-30
Author(s):  

An algorithm is proposed for calculating a closed volumetric hydraulic pump-hydraulic motor system using the example of the hydraulic system of a wind power plant, based on the calculation of the hydraulic systems of mobile machines. The main characteristics of the system components, the selection of initial data for the calculation, working fluid and diameters of hydraulic lines are analyzed. Keywords: hydraulic system, energy, fluid, oil, pump, motor, renewable energy source, wind power plant, machine. [email protected]


2012 ◽  
Vol 192 ◽  
pp. 360-364
Author(s):  
Xi Guang He ◽  
Ji Feng Xing ◽  
Jia Chen

In order to guarantee that the rudder hydraulic systems work normally, the rudder hydraulic system must supply constant-pressure fluid to it. In this article, the author had analyzed the relationship between the power of the hydraulic oil pump and its motor revs, and done researches on its controlling tactics. Next, the author deigned its controller and controlling system based on fuzzy-control theorem. This system could extend the life-span of the pump motor and save energy, and it can also be utilized in other engineering fields.


2016 ◽  
Vol 8 (3) ◽  
pp. 74-77
Author(s):  
Сазонова ◽  
Svetlana Sazonova

In practice, there are three forms of boundary conditions. The feature of the fourth form of the boundary conditions is that the relationship between the above nodal parameters before solving the problem cannot be defined neither in form nor in content. This situation occurs when the decomposition of the hydraulic system. The basis of this mechanism is to transform the basic model estimated in the secondary zone model based on the method of functional reduction. This method is essentially a synthesis of the known methods of transformation models based on the ideas of reduction, diakoptic and cybernetic modeling.


Author(s):  
José Alejandro Muñoz-Hernandez ◽  
Teresa Hernández-Ortiz ◽  
Moisés Montiel-González ◽  
Iván Salgado-Transito

This paper presents the selection of supply materials and describes the manufacturing process of a solar compound parabolic solar concentrator (CPC) to disinfect drinking water for consumption by rural communities. The volume of water to be treated is 100 liters/day, average amount of water for services of a family of 6 people, including washing of kitchen utensils and food preparation. The selection of supply materials for the CPE manufacture was made considering the lifetime, low cost and availability in the Mexican industrial market. The main components of the CPC are: 1. the profile of the involute, made of galvanized steel sheet gauge 20 (0.9 mm) with bright chrome finish to achieve a reflective surface, 2. Hydraulic system, integrated by coupling elements between 6 lines of borosilicate glass tubes of 44 mm outside diameter and 1.6 mm thickness with PVC accessories and 3. Mechanical support structure of the CPC, which was designed with a variable angle, to adjust according to the latitude of the operation site, this was manufactured with industrial processes of pailería and reinforced tubular profile (PTR) of 14 gauge steel (1.9 mm thickness) was used.


2018 ◽  
Vol 239 ◽  
pp. 04006
Author(s):  
Yuri Ezhov ◽  
Igor Zub ◽  
Natalia Pizhurina ◽  
Vladimir Sidorenko

The operation of loading machines requires special attention in the selection of materials for hydraulic devices and the development of recommendations for their operation. Competencies that should be obtained by a specialist operating the handling equipment, include the ability to analyze the operation of the hydraulic system on the basis of these devices and adjust the operating modes of the handling devices. In this paper, a number of experiments on the hydraulic bench. During the experiments, the characteristics of the pressure dependence in the lifting cylinder on the weight of the load and the lifting angle were removed. The considered algorithm of research can be used in the development of methods of laboratory work for the training of specialists in the field of operation and design of loading equipment.


Author(s):  
А. I. Grabovets ◽  
V. P. Kadushkina ◽  
S. А. Kovalenko

With the growing aridity of the climate on the Don, it became necessary to improve the methodology for conducting the  breeding of spring durum wheat. The main method of obtaining the source material remains intraspecific step hybridization. Crossings were performed between genetically distant forms, differing in origin and required traits and properties. The use of chemical mutagenesis was a productive way to change the heredity of genotypes in terms of drought tolerance. When breeding for productivity, both in dry years of research and in favorable years, the most objective markers were identified — the size of the aerial mass, the mass of grain per plant, spike, and harvest index. The magnitude of the correlation coefficients between the yield per unit area and the elements of its structure is established. It was most closely associated with them in dry years, while in wet years it decreased. Power the correlation of the characteristics of the pair - the grain yield per square meter - the aboveground biomass averaged r = 0.73, and in dry years it was higher (0.91) than in favorable ones (0.61 - 0.70) , between the harvest and the harvest index - r = 0.81 (on average). In dry years, the correlation coefficient increased to 0.92. Research data confirms the greatest importance of the mass of grain from one ear and the plant in the formation of grain yield per unit area in both dry and wet years. In dry years, the correlation coefficient between yield and grain mass per plant was on average r = 0.80; in favorable years, r = 0.69. The relationship between yield and grain mass from the ear was greater — r = 0.84 and r = 0.82, respectively. Consequently, the breeding significance of the aboveground mass and the productivity of the ear, as a criterion for the selection of the crop, especially increases in the dry years. They were basic in the selection.


2018 ◽  
Vol 2 (2) ◽  
pp. 137
Author(s):  
Muhammad Abi Berkah Nadi

Radin Inten II Airport is a national flight in Lampung Province. In this study using the technical analysis stated preference which is the approach by conveying the choice statement in the form of hypotheses to be assessed by the respondent. By using these techniques the researcher can fully control the hypothesized factors. To determine utility function for model forecasting in fulfilling request of traveler is used regression analysis with SPSS program. The analysis results obtained that the passengers of the dominant airport in the selection of modes of cost attributes than on other attributes. From the result of regression analysis, the influence of independent variable to the highest dependent variable is when the five attributes are used together with the R square value of 8.8%. The relationship between cost, time, headway, time acces and service with the selection of modes, the provision that states whether or not there is a decision. The significance of α = 0.05 with chi-square. And the result of Crame's V test average of 0.298 is around the middle, then the relationship is moderate enough.


2018 ◽  
Vol 15 (5) ◽  
pp. 429-442 ◽  
Author(s):  
Nishant Verma ◽  
S. Natasha Beretvas ◽  
Belen Pascual ◽  
Joseph C. Masdeu ◽  
Mia K. Markey ◽  
...  

Background: Combining optimized cognitive (Alzheimer's Disease Assessment Scale- Cognitive subscale, ADAS-Cog) and atrophy markers of Alzheimer's disease for tracking progression in clinical trials may provide greater sensitivity than currently used methods, which have yielded negative results in multiple recent trials. Furthermore, it is critical to clarify the relationship among the subcomponents yielded by cognitive and imaging testing, to address the symptomatic and anatomical variability of Alzheimer's disease. Method: Using latent variable analysis, we thoroughly investigated the relationship between cognitive impairment, as assessed on the ADAS-Cog, and cerebral atrophy. A biomarker was developed for Alzheimer's clinical trials that combines cognitive and atrophy markers. Results: Atrophy within specific brain regions was found to be closely related with impairment in cognitive domains of memory, language, and praxis. The proposed biomarker showed significantly better sensitivity in tracking progression of cognitive impairment than the ADAS-Cog in simulated trials and a real world problem. The biomarker also improved the selection of MCI patients (78.8±4.9% specificity at 80% sensitivity) that will evolve to Alzheimer's disease for clinical trials. Conclusion: The proposed biomarker provides a boost to the efficacy of clinical trials focused in the mild cognitive impairment (MCI) stage by significantly improving the sensitivity to detect treatment effects and improving the selection of MCI patients that will evolve to Alzheimer’s disease.


Author(s):  
A. A. Sheptulin ◽  
O. A. Storonova

Aim of review. Interpretation of published evidence on the relationship between the excessive belching syndrome and functional dyspepsia (FD) and their management in patient care.Key points. According to the Rome IV criteria of functional gastrointestinal disorders (FGID), excessive belching in the absence of other dyspeptic symptoms is to be considered a manifestation of the excessive belching syndrome, which can be of gastric or supragastric nature. Combination of high-resolution manometry and impedancemetry allows an accurate diagnosis of belching and selection of optimal treatment strategy. Belching complicated by other symptoms of dyspepsia is to be considered yet another FD symptom according to the Rome IV criteria of FGID. Prokinetics are recommended to relieve belching in such cases.Conclusion. Understanding the relationship between the excessive belching syndrome and FD requires further research.


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