Efficiency Improvement of Centrifugal Reverse Pumps

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Shahram Derakhshan ◽  
Bijan Mohammadi ◽  
Ahmad Nourbakhsh
Keyword(s):  
Navier Stokes ◽  
Efficiency Improvement ◽  
Test Rig ◽  
Pump Impeller ◽  
Flow Solver ◽  
Wide Range ◽  
The World ◽  
Gradient Based ◽  
Overall Efficiency ◽  
Turbine Mode

Pumps as turbines have been successfully applied in a wide range of small hydrosites in the world. Since the overall efficiency of these machines is lower than the overall efficiency of conventional turbines, their application in larger hydrosites is not economical. Therefore, the efficiency improvement of reverse pumps is essential. In this study, by focusing on a pump impeller, the shape of blades was redesigned to reach a higher efficiency in turbine mode using a gradient based optimization algorithm coupled by a 3D Navier–Stokes flow solver. Also, another modification was done by rounding the blades’ leading edges and hub/shroud interface in turbine mode. After each modification, a new impeller was manufactured and tested in the test rig. The efficiency was improved in all measured points by the optimal design of the blade and additional modification as the rounding of the blade’s profile in the impeller inlet and hub/shroud inlet edges in turbine mode. Experimental results confirmed the numerical efficiency improvement in all measured points. This study illustrated that the efficiency of the pump in reverse operation can be improved just by impeller modification.

Analytical Maps of Aerodynamic Damping as a Function of Operating Condition for a Compressor Profile

2006 ◽  
Author(s):  
Paul J. Petrie-Repar ◽  
Andrew McGhee ◽  
Peter A. Jacobs ◽  
Rowan Gollan
Keyword(s):  
Inviscid Flow ◽  
Operating Conditions ◽  
Navier Stokes ◽  
Compressor Cascade ◽  
Operating Condition ◽  
Flow Solver ◽  
Aerodynamic Damping ◽  
Wide Range ◽  
Contour Plots ◽  
Standard Configuration

In this paper, analytical maps of aerodynamic damping for a two-dimensional compressor cascade (Standard Configuration 10) are presented. The maps are shown as contour plots of the aerodynamic damping as a function of operating condition. The aerodynamic dampings were calculated by a linearized Navier-Stokes flow solver. The flutter boundaries over a wide range of operating conditions are clearly shown on the damping maps and were found to be strongly dependent on the mode frequency and the mode shape. Extremely low values of negative aerodynamic damping were predicted for some off-design operating conditions where flow separation occurred. A damping map was also constructed based on inviscid flow simulations. There were differences in the viscous and inviscid flutter boundaries particularly at off-design inflow angles. The extremely low values of negative aerodynamic damping were only predicted by the viscous simulations and not the inviscid simulations.

A Comprehensive Through-Flow Solver Method for Modern Turbomachinery Design

2015 ◽  
Author(s):  
Mark R. Anderson ◽  
Daryl L. Bonhaus
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
Optimization Techniques ◽  
Navier Stokes ◽  
Computationally Efficient ◽  
Dimensional Solution ◽  
Loss Model ◽  
Flow Solver ◽  
Through Flow ◽  
Wide Range

Through-flow solvers have historically played a very prominent role in the design and analysis of axial turbomachinery. While three-dimensional, Full Navier-Stokes (FNS) CFD is taking an increasing larger role, quasi-3D through-flow methods are still widely used. Automated optimization techniques that search over a wide design space, involving many possible variables, are particularly suitable for the computationally efficient through-flow solver. Pressure-based methods derived from CFD solution techniques have gradually replaced older streamline curvature methods, due to their ability to capture flow across a wide range of Mach numbers, particularly the transonic and supersonic regimes. The through-flow approach allows for the solution of the three-dimensional problem with the computational efficiency of a two-dimensional solution. Since the losses are explicitly calculated through empirically based models, the need for detailed grid resolution to capture tiny flow entities (such as wakes and boundary layers) is also greatly reduced. The combined savings can result in computational costs as much as two orders of magnitude lower than full 3D CFD methods. A state-of-the-art through-flow solver has several features that are crucial in the design process. One of these is the ability to run in both a design and an analysis mode. Also important, is the ability to generate solutions where critical components are solved using 3D FNS, while others are run using a through-flow method. Other desirable features in a through-flow solver are: an advanced equation of state, injection and extraction ability, the handling of arbitrary (non-axial) shapes, and a link to a capable geometry generation engine. Through-flow solvers represent a unique mix of higher order numerical methods (increasingly CFD-based) coupled with empirically derived models (generally meanline based). The combination of these two methods in one solver creates a particularly challenging programming problem. This paper details the techniques required to effectively generate through-flow solutions. Special attention is given to an improved off-design loss model for compressors, as well as a transonic loss model needed for high-speed compressor and turbine flows. Validation with recognized test data along with corresponding 3D FNS CFD results are presented.

Numerical Optimization of Turbomachinery Bladings

2003 ◽  
Author(s):  
S. Burguburu ◽  
C. Toussaint ◽  
C. Bonhomme ◽  
G. Leroy
Keyword(s):  
Rotor Blade ◽  
Three Dimensional ◽  
Design Procedure ◽  
Optimization Process ◽  
Navier Stokes ◽  
Initial Shape ◽  
Transonic Compressor ◽  
Wide Range ◽  
Gradient Based ◽  
Improved Design

An optimization process is used to design bladings in turbomachinery. A gradient-based method is coupled to Navier-Stokes solvers and is applied to three different bladings. A new rotor blade of a transonic compressor is designed by using a Q3D approach, with a significant efficiency improvement at the design point. The off-design behavior of this new compressor is also checked afterwards. The same Q3D approach is used on a stator blade of a turbine, but the whole stage is computed in this case. The losses are locally reduced, proving the good sensitivity of the solver. Finally, a new three-dimensional rotor blade of a compressor is designed by applying deformation functions on the initial shape. The efficiency is improved over a wide range of mass flow. The whole results indicate that the optimization process can find improved design and can be integrated in a design procedure.

Creative Strategy Used in Electronic Advertising

GIS Business ◽  
2019 ◽  
Vol 14 (6) ◽  
pp. 597-606
Author(s):  
Dr. Maha Mustafa Omer Abdalaziz
Keyword(s):  
The Internet ◽  
Business Organizations ◽  
Creative Strategy ◽  
Electronic Environment ◽  
Wide Range ◽  
The World ◽  
Technological Developments ◽  
Electronic Advertising

The study aims at the technological developments that are taking place in the world and have impacted on all sectors and fields and imposed on the business organizations and commercial companies to carry out their marketing and promotional activities within the electronic environment. The most prominent of these developments is the emergence of the concept of electronic advertising which opened a wide range of companies and businessmen to advertise And to promote their products and their work easily through the Internet, which has become full of electronic advertising, and in light of that will discuss the creative strategy used in electronic advertising;

ARTISTIC ASSIMILATION OF THE WORLD IN THE ESSAY PROSE OF M. G. ATAMANOV (BASED ON THE BOOK “I AM UDMURT. WHY DOES IT HURT?”)

2020 ◽  
Vol 14 (3) ◽  
pp. 459-464
Author(s):  
Alevtina Vasilevna Kamitova ◽  
Tatyana Ivanovna Zaitseva
Keyword(s):  
Ethnic Identity ◽  
National Identity ◽  
National Culture ◽  
Native Language ◽  
Topographic Features ◽  
Wide Range ◽  
The World ◽  
The Subject ◽  
Individual Style

The paper reflects the specificity of the fundamental ideas of the artistic world of M. G. Atamanov, which includes a wide range of literary facts from the content level of the text of the works to their poetics. A particularly important role in the works of M. G. Atamanov is played by cross-cutting themes and images that reflect the author's individual style and his idea of national-ethnic identity. The subject of the research is the book of essays “Mon - Udmurt. Maly mynym vös’?” (“I am Udmurt. Why does it hurt?”), which most vividly reflected the main spiritual and artistic searches of M. G. Atamanov, associated with his ideas about the Udmurt people. The main motives and plots of the works included in the book under consideration are accumulated around the concept of “Udmurtness”. The comprehension of “Udmurtness” is modeled in his essays through specific leit themes: native language, Udmurt people, national culture, mentality, geographic and topographic features of the Udmurt people’ places of residence, the Orthodox idea. The “Udmurt theme” is recognized and comprehended by the writer through the prism of national identity.

Potential Triazole-based Molecules for the Treatment of Neglected Diseases

2019 ◽  
Vol 26 (23) ◽  
pp. 4403-4434 ◽  
Author(s):  
Susimaire Pedersoli Mantoani ◽  
Peterson de Andrade ◽  
Talita Perez Cantuaria Chierrito ◽  
Andreza Silva Figueredo ◽  
Ivone Carvalho
Keyword(s):  
Effective Treatment ◽  
Chagas Disease ◽  
Medicinal Chemistry ◽  
Biological Activities ◽  
Neglected Diseases ◽  
Triazole Derivatives ◽  
Wide Range ◽  
The World ◽  
Great Relevance ◽  
The Moment

Neglected Diseases (NDs) affect million of people, especially the poorest population around the world. Several efforts to an effective treatment have proved insufficient at the moment. In this context, triazole derivatives have shown great relevance in medicinal chemistry due to a wide range of biological activities. This review aims to describe some of the most relevant and recent research focused on 1,2,3- and 1,2,4-triazolebased molecules targeting four expressive NDs: Chagas disease, Malaria, Tuberculosis and Leishmaniasis.

Healthcare apps on smartphones available in Brazil: a preliminary classification (Preprint)

2020 ◽  
Author(s):  
André De Faria Pereira Neto ◽  
Leticia Barbosa ◽  
Rodolfo Paolucci
Keyword(s):  
Health Promotion ◽  
Disease Prevention ◽  
Digital Health ◽  
Disease Process ◽  
World Health ◽  
Computing Device ◽  
Care Treatment ◽  
Wide Range ◽  
The World ◽  
Health Applications

UNSTRUCTURED Billions of people in the world own a smartphone. It is a low-cost, portable computing device with countless features, among which applications stand out, which are programs or software developed to meet a specific goal. A wide range of applications available ranging from entertainment and personal organization to work and education is available currently. It is a vast and profitable market. Health applications have been a means of intervention for different areas, including chronic diseases, epidemics, and health emergencies. A recently published paper in the journal with the highest impact factor in Digital Health (“Journal of Medical Internet Research”) proposes a classification of health applications. This study performs a critical analysis of this organization and presents other sort criteria. This paper also presents and analyzes the “Meu Info Saúde” (“My Health Info”) app – a pioneering government initiative focused on primary care launched by the Oswaldo Cruz Foundation. The application classification proposal that will be presented builds on the intervention strategies in the health-disease process, namely: “Health Promotion”, “Disease Prevention” and “Care, Treatment and Rehabilitation”, as defined by official documents such as the World Health Organization and the Centers for Disease Control and Prevention. Most applications present in the sample are of private and foreign origin, free to download, but with a display of ads or the sale of products and services. The sampled applications were classified as “Health Promotion”, and some applications have also been categorized as “Disease Prevention” or “Care, Treatment or Rehabilitation” because they have multiple functionalities. The applications identified as “Health Promotion” focused only on individuals’ lifestyle and their increased autonomy and self-care management capacity. From this perspective, the apps analyzed in this paper differ from the “Meu Info-Saúde” application developed at Fiocruz.

Introduction

2018 ◽  
Author(s):  
Michael C. Legaspi
Keyword(s):  
Western Culture ◽  
Profound Influence ◽  
Wide Range ◽  
The World ◽  
Way Of Thinking

This is a book about wisdom. It is an inquiry into the beginnings of a particular way of thinking about life in the world. Seen in terms of wisdom, the world is not a meaningless array of disconnected things but something that is experienced as an ordered reality. This holistic way of understanding life in the world characterized pursuits of wisdom in a two-sided classical and biblical tradition that exercised a profound influence on Western culture. This book examines the development of that tradition in a wide range of texts from Homer to Plato and in the writings of early Jewish and Christian authors.

Introduction

2018 ◽  
Author(s):  
Anna-Maria Hartmann
Keyword(s):  
Sixteenth Century ◽  
Early Modern ◽  
Literary History ◽  
First Generation ◽  
Early Modern England ◽  
Related Material ◽  
Wide Range ◽  
The World ◽  
Early English

Mythographies were books that collected, explained, and interpreted myth-related material. Extremely popular during the Renaissance, these works appealed to a wide range of readers. While the European mythographies of the sixteenth century have been utilized by scholars, the short, early English mythographies, written from 1577 to 1647, have puzzled critics. The first generation of English mythographers did not, as has been suggested, try to compete with their Italian predecessors. Instead, they made mythographies into rhetorical instruments designed to intervene in topical debates outside the world of classical learning. Because English mythographers brought mythology to bear on a variety of contemporary issues, they unfold a lively and historically well-defined picture of the roles myth was made to play in early modern England. Exploring these mythographies can contribute to previous insights into myth in the Renaissance offered by studies of iconography, literary history, allegory, and myth theory.

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