A Consolidated Model for the Turbine Operation of Centrifugal Pumps

2011 ◽  
Vol 133 (6) ◽  
Author(s):  
Punit Singh ◽  
Franz Nestmann
Keyword(s):  
Evaluation Model ◽  
Optimization Procedure ◽  
Centrifugal Pumps ◽  
Acceptance Criterion ◽  
Optimum Selection ◽  
Input Parameters ◽  
Evaluation Stage ◽  
Turbine Speed ◽  
Fixed Input ◽  
Model Segment

A consolidated model for the turbine operation of centrifugal pumps comprising accurate prediction, optimum selection, and rigorous evaluation has been the primary need and the most challenging tasks for the industry to deal with. This paper introduces a consolidated model that is developed from experimental results of different pump shapes (20–80 rpm) and turbomachine fundamentals directly resulting in the parsimony feature of the model. The model also creates a new basis for dealing with uncertainties. The prediction model segment of the consolidated model requires only the pump shape and size as input parameters for bringing out the complete turbine characteristics. The selection model segment, on the other hand, requires the site head and flow as fixed input parameters and turbine speed as the control parameter to prescribe suitable pumps available in the market. The evaluation model segment compares the absolute turbine characteristics of the suitable pumps and recommends the most suitable pump for the given site. The model also includes an acceptance criterion that relates the deviation of the “pump as turbine” operating parameters with the site parameters, and it is very useful at the evaluation stage. The features of the consolidated model are illustrated with two case studies, which highlight the importance of evaluation in addition to the prediction and basic selection of pumps operating as turbines. In order to increase the accuracy and robustness of the model, the paper recommends an optimization routine stage on the existing model that comprises results of more pump shapes (obtained through field projects or extended laboratory work). The optimization procedure suggested would come a long way to provide a lasting solution for the search of a reliable pump as turbine model.

scholarly journals Artificial neural networks for inverse design of resonant nanophotonic components with oscillatory loss landscapes

Nanophotonics ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 385-392
Author(s):  
Joeri Lenaerts ◽  
Hannah Pinson ◽  
Vincent Ginis
Keyword(s):  
Machine Learning ◽  
Optimization Procedure ◽  
Linear Mapping ◽  
Inverse Design ◽  
Design Parameters ◽  
Second Step ◽  
Input Parameters ◽  
Novel Variant ◽  
Resonant Systems ◽  
The Fourier Transform

AbstractMachine learning offers the potential to revolutionize the inverse design of complex nanophotonic components. Here, we propose a novel variant of this formalism specifically suited for the design of resonant nanophotonic components. Typically, the first step of an inverse design process based on machine learning is training a neural network to approximate the non-linear mapping from a set of input parameters to a given optical system’s features. The second step starts from the desired features, e.g. a transmission spectrum, and propagates back through the trained network to find the optimal input parameters. For resonant systems, this second step corresponds to a gradient descent in a highly oscillatory loss landscape. As a result, the algorithm often converges into a local minimum. We significantly improve this method’s efficiency by adding the Fourier transform of the desired spectrum to the optimization procedure. We demonstrate our method by retrieving the optimal design parameters for desired transmission and reflection spectra of Fabry–Pérot resonators and Bragg reflectors, two canonical optical components whose functionality is based on wave interference. Our results can be extended to the optimization of more complex nanophotonic components interacting with structured incident fields.

Simulation Tool for Inventory Models: SIMIN

2014 ◽  
Vol 3 (4) ◽  
pp. 109-124 ◽  
Author(s):  
Pratiksha Saxen ◽  
Tulsi Kushwaha
Keyword(s):  
Optimization Procedure ◽  
Inventory System ◽  
Total System ◽  
Simulation Tool ◽  
Optimization Strategy ◽  
Performance Measurements ◽  
Inventory Models ◽  
Input Parameters ◽  
Classical Models ◽  
Simulation Results

In this paper, an integrated simulation optimization model for the inventory system is developed. An effective algorithm is developed to evaluate and analyze the back-end stored simulation results. This paper proposes simulation tool SIMIN (Inventory Simulation) to simulate inventory models. SIMIN is a tool which simulates and compares the results of different inventory models. To overcome various practical restrictive assumptions, SIMIN provides values for a number of performance measurements. This tool is programmed in JAVA and is based on analytical approach to guide optimization strategy. Objective of this paper is to provide a user friendly simulation tool which gives optimized inventory model results. Simulation is carried out by providing the required values of input parameters and result is stored in the database for further comparison and study. Result is obtained in terms of the performance measurements of classical models of inventory system. Simulation results are stored in excel file and it also provides graphical results to compare the outcome. This simulation tool is interfaced with an optimization procedure based on classical models of inventory system. With the specified examples, the simulation results are obtained and analyzed rigorously. The result shows that input parameters, total system costs and capacity should be considered in the design of a practical system.

scholarly journals Evaluation of the Implementation of Online Learning during the Pandemic at SETUKPA LEMDIKLAT POLRI

2021 ◽  
Vol 8 (8) ◽  
pp. 239
Author(s):  
Eno Warsino ◽  
Agus Dudung ◽  
Wardani Rahayu
Keyword(s):  
Online Learning ◽  
Student Satisfaction ◽  
Learning Strategies ◽  
Evaluation Model ◽  
Outcome Evaluation ◽  
Evaluation Standards ◽  
Synchronous Interaction ◽  
Learning Assessments ◽  
Evaluation Stage ◽  
Three Stages

The purpose of this research is to evaluate the input stages of antecedents, transactions process, and outcomes in education and training as one of the programs in SETUKPA LEMDIKLAT POLRI. This type of research is qualitative using the Countenance Stake evaluation model which consists of three stages, namely: antecedents, transactions, and outcomes. The subjects in this study consisted of 30 trainees who were selected by purposive sampling. Data were collected through interviews, and observations. The results showed that at the antecendent evaluation stage, educators are still lacking in innovating online learning planning adjustments with models or learning schemes that are planned in advance. At the transaction evaluation stage, indicators of online learning strategies and interactive online learning do not meet the evaluation standards. The training participants stated that it was less than optimal and the synchronous interaction that occurred in the online KBM conducted by the Setukpa Lemdiklat Polri. At the outcome evaluation stage, indicators of student satisfaction with online learning, not meet the specified standards. This can be seen from the absence of a discussion forum to measure the satisfaction of online learning activities that are followed by students and the absence of online learning assessments by Gadik in the Setukpa Lemdiklat POLRI environment.

scholarly journals A MODEL FOR EVALUATING CAUSES OF WASTES AND LEAN IMPLEMENTATION IN CONSTRUCTION PROJECTS

2020 ◽  
Vol 26 (4) ◽  
pp. 331-342
Author(s):  
Usama Hamed Issa ◽  
Muwaffaq Alqurashi
Keyword(s):  
Construction Projects ◽  
Evaluation Model ◽  
Kingdom Of Saudi Arabia ◽  
Lean Implementation ◽  
Input Parameters ◽  
Level Model ◽  
Implementation Level ◽  
Traditional Construction ◽  
The Comparative Study ◽  
Fuzzy Logic Technique

The wastes in construction projects such as wastes in materials, time, resources and achieving customer needs can be minimized using the new philosophy of Lean Construction (LC). This paper proposed a two-level model based on fuzzy logic technique for evaluating Causes of Wastes (CWs) and lean implementation in construction projects. The probability of occurrence and importance of CWs were two input parameters in level 01 of the model, whereas the output was the level of waste. On the other hand, level 02 of the model depended on using three input parameters which were: level of waste, controllability level for CWs and lean implementation level, while the output was the lean effect. Several linguistic variables and logical rules were used for relating inputs and outputs and new indices were introduced. The model was applied and validated for data collected in two countries: Egypt and Kingdom of Saudi Arabia (KSA). Results demonstrated that the expected lean effect is found with a positive correlation with various levels of wastes and can be improved by increasing controllability and lean implementation levels. Regarding the comparative study between the two countries, distinct disparities in lean effect were clarified. Most measured CWs indices were different in both countries while indices values in KSA were higher than in Egypt either in waste, controllability or implementation levels. The results presented an optimum arrangement to reach an effective new lean evaluation model that could be implemented for moving the traditional construction towards LC. Finally, the model can be applied easily in most countries to help decision makers in evaluating CWs and lean implementation in their construction projects.

“Online Throughflow”: Automatic Simultaneous Simulation of an Axial Flow Turbine

2010 ◽  
Author(s):  
Norbert Schinko ◽  
Martin Marx ◽  
Martin G. Rose ◽  
Stephan Staudacher ◽  
Jochen Gier ◽  
...  
Keyword(s):  
Linear Optimization ◽  
Axial Flow ◽  
Optimization Procedure ◽  
Measured Data ◽  
Measured Variable ◽  
Experimental Parameters ◽  
Input Parameters ◽  
Chi Squared ◽  
Aero Engines ◽  
The Individual

A new turbine rig analysis method has been developed at the Institute of Aircraft Propulsion Systems (ILA) at Stuttgart University. This technique is known as “Online Throughflow” and involves the optimized adjustment of the input parameters of a Throughflow Method. The calculation is run whilst the turbine is being tested, achieving a match to measured data in about five minutes. The match between predicted and measured data is expressed as a chi-squared value. This provides a target parameter for a linear optimization procedure. Measured parameters such as inter-row static pressures, torque, mass-flow and rotational speed are used in this context. Input parameters such as row deviation and row loss are adjusted to give an optimized turbine simulation in close to real time. Less than five minutes after taking a data scan of the experimental parameters at inlet to exit from and within the turbine, a converged simulation of the turbine is available. This simulation evaluates many other parameters within the turbine that are not directly measured, e.g. circumferential exit flow angles for all rows of aerofoils. Furthermore the single values of chi-squared from every measured variable can be used to decide if there is an error in the individual measurements. The complete optimizer is programmed in LabView® and is integrated into the data acquisition system of the two-stage “Advanced Turbine Research and Demonstration Rig” (ATRD-Rig), which has been developed in a cooperation of ILA and the MTU Aero Engines (MTU). The testbed, as well as the instrumentation of the specific specimen from which all measurement values for the optimization have been taken, will additionally be described in the paper.

scholarly journals EFFECT OF STRESS PATH, SIZE AND SHAPE ON THE OPTIMUM PARAMETERS OF A BRITTLE-DUCTILE CONCRETE MODEL

2017 ◽  
Vol 9 (4) ◽  
pp. 195-206 ◽  
Author(s):  
Mojtaba LABIBZADEH ◽  
Reza HAMIDI
Keyword(s):  
Optimization Procedure ◽  
Stress Path ◽  
Bending Test ◽  
Bending Tests ◽  
Three Point Bending ◽  
Size And Shape ◽  
Optimum Parameters ◽  
Input Parameters ◽  
Shape Effects ◽  
Abaqus Software

The main purpose of this study is to investigate the effects of the stress path, size and shape of the specimen, on the optimum values of the plastic input parameters of Concrete Damaged Plasticity-CDP- model of the ABAQUS software. This study concentrates on eccentricity, dilatation angle and viscosity input parameters. To finding optimum values of the mentioned parameters, an objective function which estimates the error of the model predictions was defined and tried to minimize. For evaluating the effect of the stress path on this optimization procedure, four different standard tests were simulated by the ABAQUS software: uniaxial compression, dual compression, dual-border cut specimen and three-point bending tests. For studying the effect of the size of the specimen, the three-point bending test, with three different sizes of the beam were modeled in the ABAQUS software. Furthermore, for investigating the effect of the specimen shape on the input parameters, a notched disk in a tensile stress field was modeled. Obtained results demonstrated that the path of the stress can influence significantly on the optimum values of the input parameters, while it was revealed that the CDP model can automatically take into account the size and shape effects in the simulation.

scholarly journals Surrogate-Based Optimization of a Centrifugal Pump with Volute Casing for an Automotive Engine Cooling System

2021 ◽  
Vol 11 (23) ◽  
pp. 11470
Author(s):  
Remo De Donno ◽  
Alessia Fracassi ◽  
Antonio Ghidoni ◽  
Alessandro Morelli ◽  
Gianmaria Noventa
Keyword(s):  
Centrifugal Pump ◽  
High Performance ◽  
Cooling System ◽  
Optimization Technique ◽  
Volumetric Flow Rate ◽  
Optimization Procedure ◽  
Operating Conditions ◽  
Centrifugal Pumps ◽  
Automotive Engine ◽  
Surrogate Based Optimization

This paper investigates the capability of a surrogate-based optimization technique for the advanced design of centrifugal pumps. The centrifugal pump considered in this work is designed for the automotive cooling system and consists of an impeller, a vaneless diffuser and a volute. A fully three-dimensional geometry parametrization based on Bézier surfaces is presented. The optimization procedure includes the following software packages: Scilab for the geometric parametrization, Ansys-CFX for the CFD simulations and DAKOTA for the optimization management. The initial geometry is defined by a 0D code that provides a preliminary design of the pump, given the operating conditions, i.e., the volumetric flow rate, the head and the rotating speed. In this work an operative point typical of high performance gasoline cars is considered.

scholarly journals Assessment and optimization of economic restructuring in a small peripheral region

2013 ◽  
Vol 168 (1) ◽  
pp. 117-136
Author(s):  
Markku Tykkyläinen
Keyword(s):  
Evaluation Model ◽  
Economic Restructuring ◽  
Optimization Procedure ◽  
Peripheral Region ◽  
Regional Economic ◽  
Regional Economic Structure ◽  
Peripheral Area ◽  
Planning Methods ◽  
Development Paths ◽  
Best Fit

An evaluation model is presented which is suitable for planning methods related to the construction of regional economic scenarios. The model is constructed for assessment and optimization the regional economic structure in the medium-run. A scenario experiment was performed in a small peripheral area of Finland, Northern Karelia, in the early 1980s, and preliminary results are given regarding its ability to evaluate the course of restructuring in manufacturing in this area. The best estimates of restructuring were provided by selected individuals forming expert groups, and the best fit at this stage is achieved by the scenario representing the majority of those questioned. The optimization procedure proved to be fruitful only for finding the constraints on the possible economic development paths. The base year for the model was 1978 and the essential criterion parameters, the profitability estimates, were from the years 1974—79. These profitability parameters had changed only slightly by 1984 and 1985, so that the results remain applicable to the mid-80s and indicate that this course of the restructuring is a more permanent phenomenon.

Design of a New Type of Balance Drum to Reduce Axial Loading in Centrifugal Pumps

2019 ◽  
Author(s):  
K. A. J. Bruurs ◽  
B. P. M. van Esch ◽  
M. S. van der Schoot ◽  
E. J. J. van der Zijden
Keyword(s):  
Axial Loading ◽  
Optimization Procedure ◽  
Centrifugal Pumps ◽  
Axial Thrust ◽  
Pump Impeller ◽  
Thrust Bearings ◽  
Advantages And Disadvantages ◽  
Multistage Centrifugal Pump ◽  
New Type ◽  
Semi Empirical

Abstract In centrifugal pumps, axial thrust bearings are required to compensate for the axial loading on the pump impeller(s). These forces are mainly the result of unequal distributions of pressure on projected areas at both sides of the impeller(s). Axial loading tends to be highest in multistage pumps in which all impellers face the same direction. Balancing devices are often used to reduce the loading of the axial bearings. Common types of balancing devices are the balance drum and the balance disc. Both of them have their advantages and disadvantages. A stepped balance drum is a new concept for a balancing device that can be used in any type of turbomachinery. It combines the benefits of the balance drum and the balance disk without the drawbacks of both. In this paper, the new concept is presented along with a semi-empirical model of its performance. A CFD analysis is also presented which serves to verify the analytical model. An optimization procedure of a stepped balance drum is given using a multistage centrifugal pump as an example.

scholarly journals The Development of Pop-Up Book Learning Media in Pancasila Materials Based on Local Wisdom at Elementary School

2021 ◽  
Vol 9 (1) ◽  
pp. 57
Author(s):  
Muhamad Afandi ◽  
Sari Yustiana ◽  
Nofita Puji Kesuma
Keyword(s):  
Evaluation Model ◽  
Development Stage ◽  
Design Stage ◽  
Second Grade ◽  
Design Development ◽  
A Value ◽  
Evaluation Stage ◽  
Analysis Design ◽  
Implementation Stage ◽  
Selection Of

<p align="center"><strong>Abstract</strong></p><p><em>The Development of Pop-Up Book learning media in Pancasila Material Based on Local Wisdom at second grade of Elementary Schools was conducted to find out its feasibility, practicality and effectiveness. This study used the ADDIE (Analysis, Design, Development, Implementation, and Evaluation) model. At the Analysis stage, interviews, material analysis and student needs are carried out. Then, at the design stage, namely the selection of product formats and images are conducted. The development stage is carried out by validating the expert validator. Furthermore, the Implementation stage was tested on students and the Evaluation stage was carried out by pretest and posttest to determine the effectiveness of students. Based on these five stages, the development of Pop-Up Book Learning media resulted in the feasibility of learning media with a score of 0.90 which was obtained by four validators, then the practicality of the Pop-Up Book learning media got a value of 90.8%. The effectiveness of using the Gain Test was 0.45. and get the "moderate" criteria. Based on these results, the Pop-Up Book learning media is declared feasible, practical and effective in learning</em>.</p>

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