Improvement of Hydrodynamic Performance of a Multiphase Pump Using Design of Experiment Techniques

2015 ◽  
Vol 137 (8) ◽  
Author(s):  
Joon-Hyung Kim ◽  
Him-Chan Lee ◽  
Jin-Hyuk Kim ◽  
Young-Seok Choi ◽  
Joon-Yong Yoon ◽  
...  
Keyword(s):  
Design Optimization ◽  
Design Of Experiment ◽  
Deep Sea ◽  
Internal Flow ◽  
Fractional Factorial ◽  
Hydrodynamic Performance ◽  
Pump Efficiency ◽  
Design Variables ◽  
Optimized Model ◽  
Offshore Plants

Multiphase pumps for offshore plants must perform at high pressure because they are installed on deep-sea floors to pressurize and transfer crude oil in oil wells. As the power for operating pumps should be supplied to deep sea floors using umbilicals, risers, and flow lines (URF), which involve a higher cost to operate pumps, the improvement of pump efficiency is strongly emphasized. In this study, a design optimization to improve the hydrodynamic performance of multiphase pumps for offshore plants was implemented. The design of experiment (DOE) techniques was used for organized design optimization. When DOE was performed, the performance of each test set was evaluated using the verified numerical analysis. In this way, the efficiency of the optimization was improved to save time and cost. The degree to which each design variable affects pump performance was evaluated using fractional factorial design, so that the design variables having a strong effect were selected based on the result. Finally, the optimized model indicating a higher performance level than the base model was generated by design optimization using the response surface method (RSM). How the performance was improved was also analyzed by comparing the internal flow fields of the base model with the optimized model. It was found that the nonuniform flow components observed on the base model were sharply suppressed in the optimized model. In addition, due to the increase of the pressure performance of the optimized model, the volume of air was reduced; therefore, the optimized model showed less energy loss than the base model.

Design of experiments to investigate blade geometric effects on the hydrodynamic performance of torque converters

2017 ◽  
Vol 233 (2) ◽  
pp. 276-291 ◽  
Author(s):  
Cheng Liu ◽  
Wei Wei ◽  
Qingdong Yan ◽  
Neal R Morgan
Keyword(s):  
Design Of Experiments ◽  
Factorial Design ◽  
Reaction Force ◽  
Three Dimensional ◽  
Torque Converter ◽  
Fractional Factorial ◽  
Hydrodynamic Performance ◽  
Design Parameters ◽  
Design Variables ◽  
Torque Converters

Torque converters are key components in automatic and hydrodynamic transmissions. Power is transmitted through the reaction force of fluid on cascades; thus, the geometry of the blade is essential to torque converter performance. The traditional one-dimensional blade design approach becomes inefficient for modern torque converter design because torque converters are highly coupled turbomachines and the flow is three-dimensional. In the present research, a novel six-parameter blade camberline design was developed to describe the overall shape of the blade. A full two-level factorial design was conducted with computational fluid dynamics (CFD) simulations on each component to determine the sensitivity of design variables and investigate the relationship between design parameters and hydrodynamic performance. The design variables were reduced from 18 to nine after the screening design. A quarter-fractional factorial design was performed on the selected primary design variables to explore the first-order interaction effects between different wheels. Then a response surface was generated for each component to provide a substitution model for further optimization. A series of torque converters with various design parameters were fabricated and tested to validate the important effects determined in the design of experiments (DOE) process. It is found that CFD in combination with DOE is able to precisely capture the correlation between design variables and hydrodynamic performance. A base torque converter was optimized based on the DOE studies and the result was tested. Pronounced improvement in powertrain performance and fuel economy were observed.

Influence of the Flatness Ratio of an Automotive Torque Converter on Hydrodynamic Performance

1999 ◽  
Vol 121 (3) ◽  
pp. 614-620 ◽  
Author(s):  
E. Ejiri ◽  
M. Kubo
Keyword(s):  
Flow Characteristics ◽  
Internal Flow ◽  
Torque Converter ◽  
Hydrodynamic Performance ◽  
Pump Efficiency ◽  
Torque Transmission ◽  
Performance Deterioration ◽  
Overall Performance ◽  
Torque Converters ◽  
Shock Loss

Automotive torque converters have recently been designed with an increasingly narrower profile for the purpose of achieving a smaller axial size, which also translates into weight savings. Four torque converters with different flatness ratios were manufactured and tested in order to evaluate the change in their overall performance, including efficiency, stall torque ratio and torque transmission capacity. The experimental results show that the overall performance deteriorates when the flatness ratio is reduced to less than about 0.2. The internal flow characteristics of the torque converters were also investigated by numerical analysis using a CFD code. The computational results indicate that the main cause of this performance deterioration is a reduction in pump efficiency, which is attributed to increases in shock loss in the inlet region, separation loss in the fore half region, and friction loss in the exit region.

scholarly journals Hybrid Seven-bar Press Mechanism

2018 ◽  
Vol 12 (3) ◽  
pp. 181-187
Author(s):  
M. Erkan Kütük ◽  
L. Canan Dülger
Keyword(s):  
Genetic Algorithm ◽  
Objective Function ◽  
Design Optimization ◽  
Hybrid System ◽  
Degrees Of Freedom ◽  
Dimensional Synthesis ◽  
Design Variables ◽  
Optimization Study ◽  
Metal Stamping

An optimization study with kinetostatic analysis is performed on hybrid seven-bar press mechanism. This study is based on previous studies performed on planar hybrid seven-bar linkage. Dimensional synthesis is performed, and optimum link lengths for the mechanism are found. Optimization study is performed by using genetic algorithm (GA). Genetic Algorithm Toolbox is used with Optimization Toolbox in MATLAB®. The design variables and the constraints are used during design optimization. The objective function is determined and eight precision points are used. A seven-bar linkage system with two degrees of freedom is chosen as an example. Metal stamping operation with a dwell is taken as the case study. Having completed optimization, the kinetostatic analysis is performed. All forces on the links and the crank torques are calculated on the hybrid system with the optimized link lengths

Barrier Function Method in Reliability Based Design Optimization

2005 ◽  
Vol 297-300 ◽  
pp. 1882-1887
Author(s):  
Tae Hee Lee ◽  
Jung Hun Yoo
Keyword(s):  
Design Optimization ◽  
Barrier Function ◽  
Reliability Index ◽  
Feasible Solution ◽  
Reliability Based Design Optimization ◽  
User Requirement ◽  
Mean Values ◽  
Reliability Based Design ◽  
Design Variables ◽  
Reliability Method

In practical design applications, most design variables such as thickness, diameter and material properties are not deterministic but stochastic numbers that can be represented by their mean values with variances because of various uncertainties. When the uncertainties related with design variables and manufacturing process are considered in engineering design, the specified reliability of the design can be achieved by using the so-called reliability based design optimization. Reliability based design optimization takes into account the uncertainties in the design in order to meet the user requirement of the specified reliability while seeking optimal solution. Reliability based design optimization of a real system becomes now an emerging technique to achieve reliability, robustness and safety of the design. It is, however, well known that reliability based design optimization can often have so multiple local optima that it cannot converge into the specified reliability. To overcome this difficulty, barrier function approach in reliability based design optimization is proposed in this research and feasible solution with specified reliability index is always provided if a feasible solution is available. To illustrate the proposed formulation, reliability based design optimization of a bracket design is performed. Advanced mean value method and first order reliability method are employed for reliability analysis and their optimization results are compared with reliability index approach based on the accuracy and efficiency.

Numerical Simulation of a Jumper Conveying Slurry for Deep-Sea Mining

2021 ◽  
Author(s):  
Marcio Yamamoto ◽  
Tomo Fujiwara ◽  
Joji Yamamoto ◽  
Sotaro Masanobu
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Dynamic Analysis ◽  
Internal Pressure ◽  
Deep Sea ◽  
Petroleum Industry ◽  
Vertical Direction ◽  
Internal Flow ◽  
Horizontal Direction ◽  
Viscous Pressure

Abstract One key technology for Deep-Sea Mining is the riser system. The riser is already a field-proven technology in the Petroleum Industry. However, several differences exist between a petroleum production riser and a riser for Deep-Sea Mining, mainly related to the internal flow. The ore-slurry has a larger density than the hydrocarbons and shall be pumped with a much higher flowrate. The current software tools for riser’s dynamic analysis may include the internal fluid hydrostatic pressure and the centrifugal and Coriolis forces imposed by the bent pipe’s internal flow. However, the internal pressure drop is not calculated. The internal pressure alters the pipe’s effective tension and can alter the pipe’s bending moment changing its mechanical behavior. This article describes a computational script’s development to run embedded in a commercial software for riser’s dynamic analysis. Our script calculates the internal viscous pressure drop along with the jumper. This pressure is then converted into wall axial tension (buckling) and imposed on each node of the jumper’s numerical model. Each simulation case was calculated twice with and without the internal flow viscous pressure drop. The comparison with experimental data revealed that the jumper’s average position has a good agreement among all cases. However, the amplitude caused by the top oscillation showed some discrepancies. Experimental data has the highest amplitude in the horizontal direction, while the simulation without viscous pressure calculation had the smallest. The simulation with our embedded script had intermediary amplitude in the horizontal direction. The vertical direction amplitudes have the same behavior for all cases, but the experimental data showed the highest amplitude.

Optimization of a vacuum cleaner fan suction and shaft power using Kriging surrogate model and MIGA

2021 ◽  
pp. 095765092110496
Author(s):  
Soheil Almasi ◽  
Mohammad Mahdi Ghorani ◽  
Mohammad Hadi Sotoude Haghighi ◽  
Seyed Mohammad Mirghavami ◽  
Alireza Riasi
Keyword(s):  
Optimization Design ◽  
Optimization Technique ◽  
Internal Flow ◽  
Latin Hypercube Sampling ◽  
Sample Space ◽  
Geometrical Parameters ◽  
Vacuum Cleaner ◽  
Time Saving ◽  
Design Variables ◽  
Shaft Power

Optimization of vacuum cleaner fan components is a low-cost and time-saving solution to satisfy the increasing requirement for compact energy-efficient cleaners. In this study, surrogate-based optimization technique is used and for the first time it is focused on maximization of Airwatt parameter, which describes the fan suction power, as an objective function (Case II). Besides, the shaft power is minimized (Case I) as another optimization target in order to reduce the power consumption of the vacuum cleaner. 11 geometrical variables of 3 fan components including impeller, diffuser and return channel are selected as the optimization design variables. 80 training points are distributed in the sample space using Advanced Latin Hypercube Sampling (ALHS) technique and the outputs of sample points are calculated by means of CFD simulations. Kriging and RSA surrogate models have been fitted to the outputs of the sample space. Through coupling of constructed Kriging models and Multi-Island Genetic Algorithm (MIGA), the optimal design for each of the optimization cases is presented and evaluated using numerical simulations. A 20.22% reduction in shaft power in Case I and an improvement of 27.73% in Airwatt in Case II have been achieved as the overall results of this study. Despite achieving goals in both optimization cases, a slight decrease in Airwatt in Case I (−6.20%) and a slight increase in shaft power in Case II (+4.82%) are observed relative to primary fan. Furthermore, the Analysis of Variance (ANOVA) determines the importance level of design variables and their 2-way interactions on the objective functions. It was concluded that geometrical parameters related to all of the fan components must be considered simultaneously to conduct a comprehensive optimization. The reasons of enhancement in optimal cases compared with the reference design have been further investigated by analysis of the fan internal flow field. Post-processing of the CFD results demonstrates that the applied geometrical modifications cause a more uniform flow through the flow passages of the optimal fan components.

Aerodynamic Automobile Shape Optimization by Incorporating Reverse Shape Design Method With CFD Analysis

2017 ◽  
Author(s):  
Kisun Song ◽  
Kyung Hak Choo ◽  
Jung-Hyun Kim ◽  
Dimitri N. Mavris
Keyword(s):  
Design Optimization ◽  
Aerodynamic Drag ◽  
Design Method ◽  
Shape Design ◽  
Cfd Analysis ◽  
Simple Arithmetic ◽  
Design Variables ◽  
3D Geometry ◽  
Geometric Entity ◽  
Aerodynamic Drag Reduction

In modern automotive industry market, there have been a lot of state-of-art methodologies to perform a conceptual design of a car; functional methods and 3D scanning technology are widely used. Naturally, the issues frequently boiled down to a trade-off decision making problem between quality and cost. Besides, to incorporate the design method with advanced optimization methodologies such as design-of-experiments (DOE), surrogate modeling, how efficiently a method can morph or recreate a vehicle’s shape is crucial. This paper accomplishes an aerodynamic design optimization of rear shape of a sedan by incorporating a reverse shape design method (RSDM) with the aforementioned methodologies based on CFD analysis for aerodynamic drag reduction. RSDM reversely recovers a 3D geometry of a car from several 2D schematics. The backbone boundary lines of 2D schematic are identified and regressed by appropriate interpolation function and a 3D shape is yielded by a series of simple arithmetic calculations without losing the detail geometric features. Besides, RSDM can parametrize every geometric entity to efficiently manipulate the shape for application to design optimization studies. As the baseline, an Audi A6 is modeled by RSDM and explored through CFD analysis for model validation. Choosing six design variables around the rear shape, 77 design points are created to build neural networks. Finally, a significant amount of CD reduction is obtained and corresponding configuration is validated via CFD.

Multi Objective Design Optimization of Two Bar Truss Using NSGA II and TOPSIS

2014 ◽  
Vol 984-985 ◽  
pp. 419-424
Author(s):  
P. Sabarinath ◽  
M.R. Thansekhar ◽  
R. Saravanan
Keyword(s):  
Design Optimization ◽  
Optimization Problems ◽  
Optimization Methods ◽  
Optimal Solutions ◽  
Objective Functions ◽  
Nsga Ii ◽  
Multi Objective ◽  
Total Displacement ◽  
Design Variables ◽  
Conflicting Objectives

Arriving optimal solutions is one of the important tasks in engineering design. Many real-world design optimization problems involve multiple conflicting objectives. The design variables are of continuous or discrete in nature. In general, for solving Multi Objective Optimization methods weight method is preferred. In this method, all the objective functions are converted into a single objective function by assigning suitable weights to each objective functions. The main drawback lies in the selection of proper weights. Recently, evolutionary algorithms are used to find the nondominated optimal solutions called as Pareto optimal front in a single run. In recent years, Non-dominated Sorting Genetic Algorithm II (NSGA-II) finds increasing applications in solving multi objective problems comprising of conflicting objectives because of low computational requirements, elitism and parameter-less sharing approach. In this work, we propose a methodology which integrates NSGA-II and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) for solving a two bar truss problem. NSGA-II searches for the Pareto set where two bar truss is evaluated in terms of minimizing the weight of the truss and minimizing the total displacement of the joint under the given load. Subsequently, TOPSIS selects the best compromise solution.

A Fractional-Factorial Numerical Technique for Stress Analysis of Glass-To-Metal Lead Seals

1994 ◽  
Vol 116 (2) ◽  
pp. 98-104 ◽  
Author(s):  
Barry Mathieu ◽  
Abhijit Dasgupta
Keyword(s):  
Closed Form ◽  
Numerical Technique ◽  
Mechanical Vibration ◽  
Maximum Principal Stress ◽  
Design Guidelines ◽  
Fractional Factorial ◽  
Design Variables ◽  
Load Carrying ◽  
Glass Seals ◽  
Glass Seal

Fracture of glass seals in metallic hermetic electronic packaging is a significant failure mode because it may lead to moisture ingress and also to loss of load carrying capacity of the glass seal. Seal glasses are intrinsically brittle and their fracture is governed by the stresses generated. This study investigates stresses in lead seals caused by handling, testing, mechanical vibration, and thermal excursions. Loads considered are axial tension, bending, and twisting of the lead. More general loading can be handled by superposition of these results. Factorial techniques, commonly used in multi-variable Design of Experiments (DoE), are used in conjunction with finite element parametric simulations, to formulate closed-form regression models which relate the maximum principal stress within the glass seal to the type of loading and geometry. The accuracy of the proposed closed-form equations are verified through analysis of residuals. The analysis reveals the sensitivity of the magnitude of the seal stress to design variables such as the materials and geometry of the seal, lead, and package. Manufacturing-induced problems such as defects and flaws are not considered. An additional purpose for presenting this study is to illustrate the use of design of experiment methods for developing closed-form models and design guidelines from simulation studies, in a multi-variable problem.

Design Optimization of RML Glove for Improved Grasp Performance

2018 ◽  
Author(s):  
Teja Vanteddu ◽  
Bijo Sebastian ◽  
Pinhas Ben-Tzvi
Keyword(s):  
Design Optimization ◽  
Daily Living ◽  
Experimental Validation ◽  
Large Diameter ◽  
Future Research ◽  
Linkage Mechanism ◽  
Design Variables ◽  
Wide Range ◽  
Optimal Values ◽  
Optimal Set

This paper describes the design optimization of the RML Glove in order to improve its grasp performance. The existing design is limited to grasping objects of large diameter (> 110mm) due to its inability in attaining high bending angles. For an exoskeleton glove to be effective in its use as an assistive and rehabilitation device for Activities of Daily Living (ADL), it should be able to interact with objects over a wide range of sizes. Motivated by these limitations, the kinematics of the existing linkage mechanism was analyzed in detail and the design variables were identified. Two different cost functions were formulated and compared in their ability to yield optimal values for the design variables. The optimal set of design variables was chosen based on the grasp angles achieved and the resulting mechanism was simulated in CAD for feasibility testing. An exoskeleton mechanism corresponding to the index finger was manufactured with the chosen design variables and detailed experimental validation was performed to illustrate the improvement in grasp performance over the existing design. The paper ends with a summary of the experimental results and directions for future research.

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