scholarly journals Research on head loss of pre-pump micro-pressure filter under clean water conditions

Author(s):  
Hongfei Tao ◽  
Pingping Shen ◽  
Qiao Li ◽  
Youwei Jiang ◽  
Wenxin Yang ◽  
...  

Abstract Filters are important pieces of equipment to ensure the normal operation of micro-irrigation systems, and the head loss is a key indicator to evaluate their hydraulic performances. To reduce the head loss and energy consumption, a new type of filter for treating surface water – the pre-pump micro-pressure filter was proposed. The pre-pump micro-pressure filter was studied, and physical model tests on the flow rate, water separator type, and filter screen area were conducted under clean water conditions. Statistical and dimensional analysis methods were used to analyze the test results. Our results showed that the order of the factors affecting the head loss of the filter was flow rate > water separator type > filter screen area. The various water separator types showed no significant differences in terms of head loss, while the different flow rates showed significant differences. A head loss prediction model was constructed, and the coefficient of determination R2 reached 0.987. Our results can provide technical support for new filter development and enrich the theory of micro-pressure filtration.

2018 ◽  
Vol 152 ◽  
pp. 02015
Author(s):  
Yoong Sion Ong ◽  
Ken Sim Ong ◽  
Y.k. Tan ◽  
Azadeh Ghadimi

A conventional design of rainwater harvesting system collects and directs the rainwater through water piping from roof of building to the water storage. The filtration system which locates before the water tank storage and first flush bypass system is the main focus of the research. A filtration system consists of a control volume of filter compartment, filter screen (stainless steel mesh) and water piping that direct the water flow. The filtration efficiency of an existing filter “3P Volume Filter VF1” by industrial company is enhanced. A full scale filter design prototype with filter screen of 1000 μm stainless steel metal mesh is tested to compare with the original filter system design. Three types of water inlet setups are tested. Among the proposed water inlet setups, the 90° inlet setup with extension provides the best filtration rate per unit time, following by the 45° inlet setup. The 45° and 90° inlet setup has similar filtration efficiency at low to medium flow rate while 45° inlet setup has better efficiency at high flow rate. The filtration efficiency with the 90° inlet setup with extension is observed to maintain at highest value at medium to high flow rate. The overall filtration performance achieved by the 90° inlet setup with extension at low to high flow rate is between 34.1 to 35.7%.


Author(s):  
А.В. Саврико ◽  
С.Н. Лымич ◽  
К.В. Кружаев ◽  
В.С. Левин ◽  
А.В. Москвичев

Приведено исследование зависимости газодинамических характеристик стенда от применяемого материала трубопровода. Oсновополагающими факторами, влияющими на работоспособность стенда, являются выходные параметры - давление и расход рабочего тела, которые напрямую зависят от потерь давления на трение, создаваемого элементами стенда. Для оценки степени влияния материалов на потери стенда выбраны два вида труб: полипропиленовые и металлические. Аналитические расчёты потери давления рассматриваемых трубопроводов из различного материала показали, что трубопроводы из полипропилена предпочтительнее. Однако при проведении эксперимента получены противоположные данные, которые показали, что в полипропиленовых магистралях возможно присутствие значительного количества диафрагм: в местах пайки труб, образовавшихся в процессе изготовления. Именно этот факт способствует существенному повышению значений сопротивлений в полипропиленовых трубопроводах на 20 % по сравнению со стальными трубами, где диафрагмы отсутствуют. В результате проведения исследования был введен коэффициент, учитывающий влияние диафрагм полипропиленового трубопровода при аналитическом расчете на сопротивление. Для сохранения более точных снимаемых значений с газодинамических стендов целесообразнее использовать трубопроводы из металла, в которых рассчитать потери возможно с отклонениями до 3 % Here we give the study of the dependence of the gas-dynamic characteristics of the stand on the pipeline material used. The fundamental factors affecting the performance of the stand are the output parameters-the pressure and flow rate of the working fluid, which directly depend on the friction pressure losses created by the elements of the stand. To assess the degree of influence of materials on the losses of the stand, we selected two types of pipes: polypropylene and metal. Analytical calculations of the pressure loss of the considered pipelines made of various materials have shown that pipelines made of polypropylene are preferable. However, during the experiment, we obtained the opposite data, which showed that a significant number of diaphragms may be present in polypropylene pipelines: in the places of soldering of pipes formed during the manufacturing process. This fact contributes to a significant increase in the resistance values in polypropylene pipelines by 20 % compared to steel pipes, where there are no diaphragms. As a result of the study, we introduced a coefficient that takes into account the influence of polypropylene pipeline diaphragms in the analytical calculation of resistance. To preserve more accurate values taken from gas-dynamic stands, it is more expedient to use metal pipelines in which it is possible to calculate losses with deviations of up to 3 %


Irriga ◽  
2020 ◽  
Vol 25 (4) ◽  
pp. 697-703
Author(s):  
Fernanda Oliveira Silva ◽  
João Batista Tolentino Júnior

OTIMIZAÇÃO DO DIMENSIONAMENTO HIDRÁULICO DE UMA SUBUNIDADE DE IRRIGAÇÃO LOCALIZADA     FERNANDA OLIVEIRA DA SILVA1 E JOÃO BATISTA TOLENTINO JÚNIOR2   [1] Aluna de Pós-Graduação do Programa de Pós-Graduação em Ecossistemas Agrícolas e Naturais, Universidade Federal de Santa Catarina, Rodovia Ulysses Gaboardi, Km 3, Caixa postal 101, CEP 89520-000, Curitibanos, SC, Brasil. E-mail: [email protected] 2 Professor Adjunto, Departamento de Agricultura, Biodiversidade e Florestas, Universidade Federal de Santa Catarina, Rodovia Ulysses Gaboardi, Km 3, Caixa postal 101, CEP 89520-000, Curitibanos, SC, Brasil. E-mail: [email protected]     1 RESUMO   O dimensionamento do sistema de irrigação é limitado pela uniformidade, e consequentemente, pela perda de carga e topografia da área. Uma das principais tarefas do dimensionamento hidráulico de um sistema de irrigação por gotejamento é determinar as características geométricas de diâmetro da tubulação, a pressão no sistema e a uniformidade em fase de projeto. Neste trabalho, utilizou-se o método do backstep para determinar a vazão, perda de carga e pressão no sistema. O modelo foi desenvolvido para atender condições sem declividade, em aclive e em declive. Aplicou-se o método da bisseção para otimizar o dimensionamento hidráulico para uma única linha lateral ou para uma subunidade de irrigação por gotejamento. Determinou-se o diâmetro interno da linha lateral e de derivação para atender a uma uniformidade de distribuição de água acima de 90%. Definiu-se a pressão no final da linha lateral e de derivação para atender a condição de vazão média requerida nos emissores. Com o avanço da tecnologia, consegue-se implementar em linguagem computacional equações complexas e chegar a um ótimo dimensionamento hidráulico. As equações foram implementadas em linguagem R, no formato de função, e mostraram ser uma ferramenta rápida e simples para o dimensionamento hidráulico de sistemas de irrigação.   Palavras-chave: backstep, bisseção, modelagem hidráulica.       SILVA, F. O. E TOLENTINO JÚNIOR, J. B. OPTIMIZATION OF HYDRAULIC DESIGN OF A MICROIRRIGATION SYSTEM     2 ABSTRACT   The design of the irrigation system is limited by the uniformity and, consequently, by the head loss and topography of the area.  One of the main tasks of the hydraulic design of a microirrigation system is to determine the geometric characteristics of pipe diameter, the pressure in the system and uniformity in the design phase.  In this work, the backstep method was used to determine the flow rate, head loss and pressure in the system. The model was developed to meet conditions without slope, uphill and downhill. The bisection method was used to optimize the hydraulic design for a single lateral line or to a microirrigation subunit. The inner diameter of the lateral line and the manifold was determined to meet a water distribution uniformity over 90%. The pressure was defined at the end of the lateral line and manifold to meet the mean flow rate condition required in the emitters. With the advancement of technology, it is possible to implement computational language complex equations and reach a great hydraulic design. The equations were implemented in the R language, in function format, and proved to be a fast and simple tool for the system hydraulic dimensioning of irrigation.    Keywords: backstep, dissection, hydraulic modeling.


2019 ◽  
Vol 18 (3) ◽  
pp. 89-99
Author(s):  
Vinh Huy Chau ◽  
Anh Thu Vo ◽  
Ba Tuan Le

Abstract As a up and coming sport, powerlifting is gathering more and more attetion. Powerlifters vary in their strength levels and performances at different ages as well as differing in height and weight. Hence the questions arises on how to establish the relationship between age and weight. It is difficult to judge the performance of athletes by artificial expertise, as subjective factors affecting the performance of powerlifters often fail to achieve the desired results. In recent years, artificial intelligence has made groundbreaking strides. Therefore, using artificial intelligence to predict the performance of athletes is among one of many interesting topics in sports competitions. Based on the artificial intelligence algorithm, this research proposes an analysis model of powerlifters’ performance. The results show that the method proposed in this paper can predict the best performance of powerlifters. Coefficient of determination-R2=0.86 and root-mean-square error of prediction-RMSEP=20.98 demonstrate the effectiveness of our method.


Author(s):  
Sachin Dev Suresh ◽  
Ali Qasim ◽  
Bhajan Lal ◽  
Syed Muhammad Imran ◽  
Khor Siak Foo

The production of oil and natural gas contributes to a significant amount of revenue generation in Malaysia thereby strengthening the country’s economy. The flow assurance industry is faced with impediments during smooth operation of the transmission pipeline in which gas hydrate formation is the most important. It affects the normal operation of the pipeline by plugging it. Under high pressure and low temperature conditions, gas hydrate is a crystalline structure consisting of a network of hydrogen bonds between host molecules of water and guest molecules of the incoming gases. Industry uses different types of chemical inhibitors in pipeline to suppress hydrate formation. To overcome this problem, machine learning algorithm has been introduced as part of risk management strategies. The objective of this paper is to utilize Machine Learning (ML) model which is Gaussian Process Regression (GPR). GPR is a new approach being applied to mitigate the growth of gas hydrate. The input parameters used are concentration and pressure of Carbon Dioxide (CO2) and Methane (CH4) gas hydrates whereas the output parameter is the Average Depression Temperature (ADT). The values for the parameter are taken from available data sets that enable GPR to predict the results accurately in terms of Coefficient of Determination, R2 and Mean Squared Error, MSE. The outcome from the research showed that GPR model provided with highest R2 value for training and testing data of 97.25% and 96.71%, respectively. MSE value for GPR was also found to be lowest for training and testing data of 0.019 and 0.023, respectively.


Author(s):  
Александр Викторович Стерхов

The purpose of the article is to build a model for estimating the relative premium in mergers and acquisitions of electric power companies, based on four groups of factors: the company's operating and financial results, the country affiliation, the industry affiliation, the debt market conjuncture. The research methodology is based on a comparative business valuation method. The empirical base of the research includes data on 6504 deals that occurred throughout the world from 1997 to 2018. The research database includes data on both public and non-public companies for which the amount paid in the deal is known, as well as the value of total assets. The scientific novelty consists in clarifying the conceptual apparatus (the concept of relative premium in a deal has been introduced); the selection and grouping of factors affecting the size of the relative premium; identifying and quantifying the influence of variables included in each group of factors. The article proposed the author's approach to the grouping of countries and industries, based on the equality of premium coefficients in the regression and obtained groups of countries and industries with equal premiums. It is shown that the grouping of industries, obtained by the mathematical algorithm, almost completely corresponds to the industry structure of the electric power industry. The coefficient of determination of the final econometric model is more than 20 per cent, which can be estimated as a high-quality assessment. That is because the relative premium, not the amount paid in the deal, is predicted which is in close correlation with the value of the company's assets. The practical significance of the research study consists in the possibility of predicting the value of a business, as well as determining the value paid in a deal in cases where such information is not available in available sources.


2020 ◽  
Vol 8 (2) ◽  
pp. 36
Author(s):  
Racha Medjda Bouchenak Khelladi ◽  
Abdelghani Chiboub Fellah ◽  
Maxime Pontié ◽  
Fatima Zohra Guellil

Sand filtration is an eco-friendly method to treat either drinking water or wastewater ; it requires only natural granular media. It is also easy to use and to maintain ; the only problem they face is clogging that affects filter performance, that can be detected when head loss or turbidity increase. The purpose of this work is to see what are the factors that influence the performance of filter operation, for this, we used a pilot consisting on a circular column filled with sand (from South Algeria), where various parameters were tested; pressure, flow rate, sand granulometry, suspended matters and particle concentration of the water which is filtered. After eighteen weeks of operation, we have found that head loss increases by decreasing granulometry and increasing flow rate, pressure, particle size, and concentration. However, turbidity increases by decreasing particle size and increasing granulometry and particle concentration. Turbidity and head loss have different behaviour towards the same parameter; that is why it is necessary to take them into account in order to find a compromise between acceptable head loss / turbidity for a good functioning of the filter.


2013 ◽  
Vol 423-426 ◽  
pp. 807-810
Author(s):  
Heng Quan ◽  
Yun Shan Wang ◽  
Li Feng Liu ◽  
Shao Jun Liu ◽  
Qing Ruo Meng

Mathematical-physical model of powder stream in coaxial powder feeding was established. The concentration fields of powder stream of coaxial nozzle of different size and powder mass flow rate were analyzed. The concentration field and morphology of the powder stream were detected by CCD camera. The results show that the size of coaxial nozzle and powder mass flow rate are major factors affecting the powder stream. The mathematical-physical model and experimental data provide theoretical basis for laser cladding manufacturing.


2014 ◽  
Vol 488-489 ◽  
pp. 48-52
Author(s):  
Zhi Qiang Fu ◽  
Yi Ren ◽  
Cheng Biao Wang ◽  
Wen Yue ◽  
Song Sheng Lin

The influence of sputtering power, N2 flow rate, ion current and substrate temperature on the monolayer TiN films deposited by ion beam assisted magnetron sputtering and the effect of the on-off ratio and deposition period on the multilayered Ti/TiN films was studied. It was found that the key factors affecting surface defects of monolayer TiN films are sputtering power and N2 flow rate while ion current is the most significant factor affecting the hardness of monolayer TiN films. The surface defects can be greatly inhibited by pulsed gas feeding. The adhesion and hardness of the multilayered Ti/TiN films is improved with increasing on-off ratio or decreasing deposition period; the on-off ratio has a negligible effect on the surface defects of the multilayered Ti/TiN films while the surface defects of the multilayered Ti/TiN films become more obvious at a long deposition period.


The Condor ◽  
2002 ◽  
Vol 104 (1) ◽  
pp. 208-215 ◽  
Author(s):  
Steven R. Beissinger ◽  
Noel F. R. Snyder

Abstract Dreitz et al. (2001) analyzed the factors affecting nest success of the Snail Kite (Rostrhamus sociabilis) in Florida. They concluded that success was unrelated to water levels because Akaike's Information Criterion rated models with water-level terms as poor compared to other models. Their suite of candidate models, however, did not include models with area-specific differences in the way that water levels affect nest success. We believe that such differences should have been included among the a priori models examined, and that their best model is neither ecologically informative nor useful for management. Using the same statistical methods, we reanalyze Dreitz et al.'s data on nesting success from the five areas with sufficient years and nests for analysis (comprising 89% of their 1542 nests) and show that, when spatial effects of water levels are included, water levels have an important influence on nest success over the entire range of water levels, not just during low water conditions. Furthermore, Dreitz et al.'s definition of nesting attempts excluded nests found during the 10–21 day pre-laying period, when many nests fail. Thus, they overestimated nest success and underestimated the amount of nesting activity under low water conditions. Low water conditions occur relatively frequently throughout much of the kite's range, and under these conditions few kites nest and even fewer fledge young. The effects of low water extend well beyond nest success, causing many kites to forgo nesting altogether, shortening the breeding season, and decreasing the opportunity for multiple brooding. Los Niveles de Agua Afectan el Éxito de Nidos de Rostrhamus sociabilis en Florida: Criterio de Información de Akaike y la Omisión de Modelos Potenciales Relevantes Resumen. Dreitz et al. (2001) analizaron los factores que afectan el éxito de anidación de Rostrhamus sociabilis en Florida. Ellos concluyeron que el éxito no está relacionado con los niveles de agua porque según el Criterio de Información de Akaike, los modelos que incluían términos relacionados con el nivel de agua eran de poco valor en comparación con otros modelos. Sin embargo, entre los modelos evaluados no incluyeron aquellos con diferencias específicas de área en la manera en que los niveles de agua afectan el éxito de los nidos. Nosotros creemos que dichas diferencias han debido ser incluidas en los modelos evaluados a priori y que su mejor modelo no es ecológicamente informativo ni útil en términos de manejo. Utilizando los mismos métodos estadísticos, reanalizamos los datos de éxito de anidación de Dreitz et al. de las cinco áreas que tenían suficientes años y nidos para analizar (comprendiendo el 89% de sus 1542 nidos). Demostramos que cuando se incluyen los efectos espaciales de los niveles de agua, éstos tienen una influencia importante en el éxito de los nidos en todo el rango de niveles de agua (no sólo en condiciones de aguas bajas). Más aún, la definición de intentos de anidación empleada por Dreitz et al. excluyó a aquellos nidos encontrados durante el período de 10 a 21 días pre-postura, cuando muchos nidos fracasan. Por lo tanto, ellos sobreestimaron el éxito de los nidos y subestimaron la cantidad de actividad de anidación en condiciones de aguas bajas. Las condiciones de aguas bajas se presentan con relativa frecuencia en gran parte del rango de distribución de R. sociabilis. Bajo esas condiciones, pocos individuos anidan y aún menos crían polluelos exitosamente. Los efectos de aguas bajas se extienden más allá del éxito de los nidos, causando que muchos individuos totalmente renuncien a anidar, acortando la época reproductiva y reduciendo las oportunidades de tener múltiples nidadas.


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