scholarly journals A Performance Prediction Method for Pumps as Turbines (PAT) Using a CFD Modeling Approach

2016 ◽  
Author(s):  
Emma Frosina ◽  
Dario Buono ◽  
Adolfo Senatore
Keyword(s):  
Test Bench ◽  
Low Cost ◽  
Three Dimensional ◽  
Prediction Method ◽  
Cfd Modeling ◽  
Centrifugal Pumps ◽  
Software Model ◽  
Pumping Mode ◽  
Using Data ◽  
The University

Small and micro hydropower represents an attractive solution for electricity generation, with low cost and low environmental impact. The pump-as-turbine (PAT) approach has promise in this application owing to its low purchase and maintenance costs. In this paper, a new method to predict the inverse characteristic of industrial centrifugal pumps is presented. This method is based on results of simulations performed with commercial three-dimensional CFD software. Model results have been first validated in pumping mode using data supplied by pump manufacturers. Then, results have been compared to experimental data for a pump running in reverse condition. Experimentation has been performed on a dedicated test bench installed in the Department of Civil Construction and Environmental Engineering of the University of Naples Federico II. Three different pumps, with different specific speeds, have been analyzed. Using the model results, the inverse characteristic and the best efficiency point have been evaluated. Finally, results of this methodology have been compared to prediction methods available in the literature.

scholarly journals Four-Dimensional Map Reconstruction for Urban Progress Analysis

2020 ◽  
Vol 55 (2) ◽  
Author(s):  
Zahraa E. Hussein ◽  
Marwa M. Bori ◽  
Layla K. Abbas
Keyword(s):  
Spatial Information ◽  
Low Cost ◽  
Three Dimensional ◽  
Water Area ◽  
Google Earth ◽  
Geographical Information ◽  
Data Set ◽  
Important Indicator ◽  
3 Dimensional ◽  
The University

The article describes a simple and low cost methodology of four-dimensional map creation, based on the main elements of the urban world like such as green ground, buildings, soil, water area and others, which makes it possible to detect the urban progress during a certain period using an open source data of Google Earth and geographical information system. This implies that a study of changes in urban elementrequire an integration of spatial information and corresponding real time, which is referred to as the four-dimensional map. Accordingly, the fourth dimensional (time) was added to the three dimensional spatial information (3 dimensional) study area signifies by the University of Baghdad, Aljadrya Campus. Regarding the article, the study area’s urban progress was considered for Google Earth’s available period of the data set that started from 2002 to 2019 at each of 2002, 2005, 2010 in addition to 2019 before being updated from the field observation. The main goal of this article is to provide an important indicator that can be used to determine the nature of current growth and forecast it in the future. Furthermore, it can be used for solving the problems of negative urban progress, which is what most developing countries are experiencing. Findings show significant changes in the main objects of the study area are represented by increasing each of buildings, green grounds, play grounds by about 40.9%, 65.4% and 30.2% respectively, which are offset by decrease insoil grounds of nearly 20.8%.

scholarly journals Hyperaccumulators for Potentially Toxic Elements: A Scientometric Analysis

Agronomy ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1729
Author(s):  
Dongming Zhang ◽  
Miles Dyck ◽  
Lana Filipović ◽  
Vilim Filipović ◽  
Jialong Lv ◽  
...  
Keyword(s):  
Toxic Elements ◽  
Environmental Science ◽  
Low Cost ◽  
Potentially Toxic Elements ◽  
Collaboration Network ◽  
Scientometric Analysis ◽  
The Usa ◽  
Using Data ◽  
Number Of Publications ◽  
The University

Phytoremediation is an effective and low-cost method for the remediation of soil contaminated by potentially toxic elements (metals and metalloids) with hyperaccumulating plants. This study analyzed hyperaccumulator publications using data from the Web of Science Core Collection (WoSCC) (1992-2020). We explored the research status on this topic by creating a series of scientific maps using VOSviewer, HistCite Pro, and CiteSpace. The results showed that the total number of publications in this field shows an upward trend. Dr. Xiaoe Yang is the most productive researcher on hyperaccumulators and has the broadest international collaboration network. The Chinese Academy of Sciences (China), Zhejiang University (China), and the University of Florida (USA) are the top three most productive institutions in the field. China, the USA, and India are the top three most productive countries. The most widely used journals were the International Journal of Phytoremediation, Environmental Science and Pollution Research, and Chemosphere. Co-occurrence and citation analysis were used to identify the most influential publications in this field. In addition, possible knowledge gaps and perspectives for future studies are also presented.

Investigation of Air-Oil-Thermal Distribution in Floating Bush Bearing

2017 ◽  
Author(s):  
Yan Wang ◽  
Xiaodong Ren
Keyword(s):  
Thermal Effect ◽  
Thermal Effects ◽  
High Speed ◽  
Low Cost ◽  
Prediction Method ◽  
Cfd Modeling ◽  
Speed Ratio ◽  
Shaft Speed ◽  
Two Phase ◽  
Oil Film

Owing to their low cost and reduced power losses, floating bush bearings are extensively used in high-speed rotors. The advantages are mainly the result of the rotation of the bush. When shaft speed is within a low speed range, bush rotation speed increases linearly with shaft speed. However, the bush-to-shaft speed ratio decreases sharply when the shaft speed reaches a certain range. The mechanism of this phenomenon is not completely clear yet, and a precise prediction method has not been established. The traditional theoretical model predicts that the speed ratio remains constant even when the shaft speed reaches the certain range. Some researchers have attempted to improve the prediction model by considering thermal effect on the assumption that a temperature increase decreases the viscosity of the inner oil film and consequently reduces the speed ratio. However, temperature rise alone is insufficient to induce that much drop of speed ratio. This paper focuses on the effect of air invasion flow in the inner oil film from the axial ends and evaluates the importance of air invasion and thermal effects. Computational fluid dynamics (CFD) modeling is adopted in this study because of its capacity to handle complicated calculation domain and calculate air-oil two-phase flow. Three series of CFD simulations with different models are conducted. These models consider the thermal effect (thermal model), the air invasion effect (air model), and the combination of the thermal and air invasion effects (hybrid model). CFD results of the different models are compared to weigh the importance of each effect. The CFD calculation indicates that a substantial amount of air invades the inner oil film when the shaft speed reaches a certain range. Speed ratio drop is not caused by a single factor, but it is the result of the combination of the air invasion and thermal effects. Air invasion, which researchers previously ignored, plays a greater role than the thermal effect.

scholarly journals Fabricación digital de maquetas para la mejora de la interpretación cartográfica y el fomento de la competencia creativa = Digital manufacturing of 3D DTM models to enhance cartographic interpretation & creative competence

2017 ◽  
Vol 1 (1) ◽  
pp. 11
Author(s):  
Dámari Melían Díaz ◽  
Carlos Carbonell Carrera ◽  
José Luis Saorín Pérez ◽  
Jorge De la Torre Cantero ◽  
Norena Martín Dorta
Keyword(s):  
Low Cost ◽  
Three Dimensional ◽  
Digital Manufacturing ◽  
Master's Students ◽  
Terrain Models ◽  
Preliminary Validation ◽  
Before And After ◽  
Manufacturing Technologies ◽  
The University ◽  
Academic Year

ResumenEn educación superior, para las titulaciones de ingeniería y arquitectura es precisa la adquisición y desarrollo de competencias como la creatividad y la visión espacial. La competencia espacial se puede desarrollar mediante la realización de ejercicios y la creatividad mejora, si el diseño de los ejercicios permite múltiples soluciones. La comprensión del relieve topográfico es necesaria para la integración de proyectos de arquitectura e ingeniería en el entorno. Sin embargo, en la formación universitaria se han detectado carencias para la interpretación de las formas del relieve. Las maquetas de terreno, pueden ayudar a suplir esta carencia. La aparición de tecnologías de fabricación digital de bajo coste permiten la creación de maquetas de terreno y su incorporación en la docencia reglada. En este artículo se presentan los resultados de dos experiencias. En la primera, llevada a cabo durante el curso 2015-16 con 33 alumnos universitarios, se realizan maquetas topográficas utilizando secciones apiladas, con el objetivo de mejorar la interpretación tridimensional de las formas del terreno. La segunda parte de la experiencia, llevada a cabo durante el curso 2016-17 se realiza con alumnos de Máster. Se trata de una validación preliminar, con pocos alumnos, en la que se pretende incorporar aspectos creativos a la realización de maquetas de terrenos. Para medir la variación de la competencia creativa en los alumnos se utiliza el Test de Abreacción de la Creatividad (TAEC), antes y después de la experiencia.AbstractIn higher education, engineering and architecture degrees require the acquisition and development of skills such as creativity and spatial ability. Space competence can be developed by performing exercises and the creativity improves, if the design of the exercises allows multiple solutions. The understanding of topographic relief is necessary for the integration of architectural and engineering projects in the environment. However, in the university context deficiencies have been detected for the interpretation of the relief forms. Land models can help to fill this gap. The emergence of low cost digital manufacturing technologies allows the creation of terrain models and their incorporation for teaching. This article presents the results of two experiences. In the first one, carried out during the 2015-16 academic year with 33 university students, topographic models are made using stacked sections, with the aim of improving the three-dimensional interpretation of the terrain forms. The second part of the experience, performed during the 2016-17 course is carried out with Master's students. This is a preliminary validation, with few students, which seeks to incorporate creative aspects to the realization of land models. To measure the variation of creative competence in students, the Creativity Abreaction Test (TAEC) is used, before and after the experience.

Characterization of the Wave Profile in the Edinburgh Curved Tank

2006 ◽  
Author(s):  
Joa˜o M. B. P. Cruz ◽  
Remy R. C. Pascal ◽  
Jamie R. M. Taylor
Keyword(s):  
Three Dimensional ◽  
Experimental Methodology ◽  
Irregular Wave ◽  
Wave Patterns ◽  
University Of Edinburgh ◽  
Using Data ◽  
The University ◽  
The Waves

A novel wave tank has been in use at the University of Edinburgh since 2003. Its main innovation is in the layout of the absorbing/wave-maker paddles, which are arranged in a 90-degree arc in an attempt to improve the angular spread of the generated three-dimensional sea states, and to minimise cross-tank seiches. This paper reports on current studies that aim to assess the quality of the waves in the tank. Directional regular and irregular wave analysis is conducted using data from two arrays of wave elevation probes. Comparisons with the expected wave patterns are made. Emphasis is given to the description of the experimental methodology. The study should prove particularly relevant in the design of a future circular combined wave and current tank.

Spectraplot: A PC-based spectrum translation and display program

1988 ◽  
Vol 46 ◽  
pp. 918-919
Author(s):  
H. O. Colijn
Keyword(s):  
Low Cost ◽  
Transfer Program ◽  
File Transfer ◽  
Transfer Data ◽  
Error Checking ◽  
Data Files ◽  
The University

Many labs today wish to transfer data between their EDS systems and their existing PCs and minicomputers. Our lab has implemented SpectraPlot, a low- cost PC-based system to allow offline examination and plotting of spectra. We adopted this system in order to make more efficient use of our microscopes and EDS consoles, to provide hardcopy output for an older EDS system, and to allow students to access their data after leaving the university.As shown in Fig. 1, we have three EDS systems (one of which is located in another building) which can store data on 8 inch RT-11 floppy disks. We transfer data from these systems to a DEC MINC computer using “SneakerNet”, which consists of putting on a pair of sneakers and running down the hall. We then use the Hermit file transfer program to download the data files with error checking from the MINC to the PC.

UPAYA MENINGKATKAN AKTIVITAS DAN HASIL BELAJAR MAHASISWA MELALUI PENERAPAN MODEL PEMBELAJARAN INKUIRI PADA MATA KULIAH KONSEP DASAR IPA 2 DI PROGRAM STUDI PENDIDIKAN GURU SEKOLAH DASAR TAHUN AKADEMIK 2013/2014

2014 ◽  
Vol 3 (1) ◽  
pp. 23
Author(s):  
Mahmud Alpusari
Keyword(s):  
Initial Data ◽  
Learning Outcomes ◽  
Inquiry Learning ◽  
Learning Activities ◽  
Simple Experiment ◽  
Competency Based ◽  
Basic Concepts ◽  
Using Data ◽  
The University ◽  
Daily Test

In line with the competency-based curriculum at the University of Riau, the effort to improvelearning basic concepts of science 2 courses puts emphasis on understanding the concept ofmatter, which is based on students' learning activities through scientific inquiry.Implementation of action research consists of two cycles in PGSD JIP University of Riau onthe odd semester of 2013/2014 with 55 third semester students. Based on the research results,lecturing process by applying the model of inquiry learning, students’ activity increased inwhich in the first cycle all activities are good category except activity I and II are faircategory. Meanwhile students’ activity in first and fourth in cycle II is good category, andvery good category in second, third, fifth, and sixth activity. Temporarily student’s learningoutcomes increased from pre-tests with an average65.45 into 77,0 in daily test I and 77.45onthe daily test II. Improvement from initial data to the first cycle was 11.55, while the datafrom the beginning to the second cycle increased 12 points. In general the improvement ofstudents’learning is possible because the learning model used is inquiry learning so thatlearning becomes active which centered into students by presenting a problem, then studentsare asked to carry out a simple experiment using equipment and tools, using data, arrangingreports, communicating the results of observations based on concepts and learned principles.Keywords: Inquiry, students’ activity, learning outcomes.

Validation of a Belt Model for Prediction of Hub Forces from a Rolling Tire4

2009 ◽  
Vol 37 (2) ◽  
pp. 62-102 ◽  
Author(s):  
C. Lecomte ◽  
W. R. Graham ◽  
D. J. O’Boy
Keyword(s):  
Internal Pressure ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Prediction Method ◽  
Analytical Models ◽  
Beam Model ◽  
Impedance Boundary ◽  
Bending Waves ◽  
Tire Rotation ◽  
Three Dimensional Models

Abstract An integrated model is under development which will be able to predict the interior noise due to the vibrations of a rolling tire structurally transmitted to the hub of a vehicle. Here, the tire belt model used as part of this prediction method is first briefly presented and discussed, and it is then compared to other models available in the literature. This component will be linked to the tread blocks through normal and tangential forces and to the sidewalls through impedance boundary conditions. The tire belt is modeled as an orthotropic cylindrical ring of negligible thickness with rotational effects, internal pressure, and prestresses included. The associated equations of motion are derived by a variational approach and are investigated for both unforced and forced motions. The model supports extensional and bending waves, which are believed to be the important features to correctly predict the hub forces in the midfrequency (50–500 Hz) range of interest. The predicted waves and forced responses of a benchmark structure are compared to the predictions of several alternative analytical models: two three dimensional models that can support multiple isotropic layers, one of these models include curvature and the other one is flat; a one-dimensional beam model which does not consider axial variations; and several shell models. Finally, the effects of internal pressure, prestress, curvature, and tire rotation on free waves are discussed.

Fabrication of 3D Temperature Sensor Using Magnetostrictive Inkjet Printhead

2020 ◽  
Vol 64 (5) ◽  
pp. 50405-1-50405-5
Author(s):  
Young-Woo Park ◽  
Myounggyu Noh
Keyword(s):  
Flexible Electronics ◽  
Inkjet Printing ◽  
Temperature Sensor ◽  
Computer Aided Design ◽  
Low Cost ◽  
Three Dimensional ◽  
Drop On Demand ◽  
Aided Design ◽  
Nanoparticle Ink ◽  
Inkjet Printhead

Abstract Recently, the three-dimensional (3D) printing technique has attracted much attention for creating objects of arbitrary shape and manufacturing. For the first time, in this work, we present the fabrication of an inkjet printed low-cost 3D temperature sensor on a 3D-shaped thermoplastic substrate suitable for packaging, flexible electronics, and other printed applications. The design, fabrication, and testing of a 3D printed temperature sensor are presented. The sensor pattern is designed using a computer-aided design program and fabricated by drop-on-demand inkjet printing using a magnetostrictive inkjet printhead at room temperature. The sensor pattern is printed using commercially available conductive silver nanoparticle ink. A moving speed of 90 mm/min is chosen to print the sensor pattern. The inkjet printed temperature sensor is demonstrated, and it is characterized by good electrical properties, exhibiting good sensitivity and linearity. The results indicate that 3D inkjet printing technology may have great potential for applications in sensor fabrication.

Constructive Optimisation of the Propeller Type Mixing Devices Using the Virtual and Rapid Prototyping

2017 ◽  
Vol 68 (3) ◽  
pp. 453-458 ◽  
Author(s):  
Daniel Besnea ◽  
Alina Spanu ◽  
Iuliana Marlena Prodea ◽  
Gheorghita Tomescu ◽  
Iolanda Constanta Panait
Keyword(s):  
Rapid Prototyping ◽  
Low Cost ◽  
Scale Up ◽  
Three Dimensional ◽  
Rapid Identification ◽  
Multidisciplinary Optimization ◽  
External Diameter ◽  
Process Industries ◽  
Parametric Cad ◽  
Shaft Torque

The paper points out the advantages of rapid prototyping for improving the performances/constructive optimization of mixing devices used in process industries, here exemplified to propeller types ones. The multidisciplinary optimization of the propeller profile affords its design using parametric CAD methods. Starting from the mathematical curve equations proposed for the blade profile, it was determined its three-dimensional virtual model. The challenge has been focused on the variation of propeller pitch and external diameter. Three dimensional ranges were manufactured using the additive manufacturing process with Marker Boot 3D printer. The mixing performances were tested on the mixing equipment measuring the minimum rotational speed and the correspondent shaft torque for complete suspension achieved for each of the three models. The virtual and rapid prototyping method is newly proposed by the authors to obtain the basic data for scale up of the mixing systems, in the case of flexible production (of low quantities), in which both the nature and concentration of the constituents in the final product varies often. It is an efficient and low cost method for the rapid identification of the optimal mixing device configuration, which contributes to the costs reduction and to the growing of the output.

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