scholarly journals Non-Axisymmetric Shroud Profiled Endwall Optimization of an Embedded Stator and Experimental Investigation

Energies ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 726
Author(s):  
Jiayu Wang ◽  
Jun Hu ◽  
Chao Jiang ◽  
Jun Li
Keyword(s):  
Energy Conversion ◽  
Objective Function ◽  
Optimization Design ◽  
Design Method ◽  
Optimization Method ◽  
Energy Conversion Efficiency ◽  
Loss Coefficient ◽  
Local Loss ◽  
Real Effects ◽  
Multi Stage

Turbomachinery has been widely used in the energy systems as an energy conversion device, such as gas turbine and aero-engine. The losses in the turbomachinery, especially in the multi-stage conditions, restrict the energy conversion efficiency and corresponding fuel economy. Previous studies show that non-axisymmetric endwall could be used to decrease the losses in compressors, but the real effects in the rig tests are usually inconsistent with the numerical simulation. In this paper, a shroud profiled endwall optimization method with the strategy of local loss as the objective function is proposed, aiming at reducing the tip loss of an embedded stator under the operating point. The traditional total loss coefficient and four local loss functions are studied to investigate how the objective functions influence the optimization results. Three optimized endwall geometries are tested in the embedded test platform. It showed that the strategy of loss coefficient above 90% span as the objective function was best at decreasing the stator loss in the tip region as well as the whole span. Under this strategy, the loss above 90% span was suppressed by 48.17% and the loss of the whole span decreased 9.27%, which proved the PEW optimization design method with the strategy of local loss as the objective function is potential.

Optimization Research on Dynamic Balance of Spatial Engine under Limiting Shaking Moment

2009 ◽  
Vol 626-627 ◽  
pp. 693-698
Author(s):  
Yong Yong Zhu ◽  
S.Y. Gao
Keyword(s):  
Mathematical Model ◽  
Objective Function ◽  
Kinetic Analysis ◽  
Optimization Design ◽  
Design Method ◽  
Dynamic Balance ◽  
Optimized Design ◽  
Design Variables ◽  
The Mathematical Model ◽  
Shaking Moment

Dynamic balance of the spatial engine is researched. By considering the special wobble-plate engine as the model of spatial RRSSC linkages, design variables on the engine structure are confirmed based on the configuration characters and kinetic analysis of wobble-plate engine. In order to control the vibration of the engine frame and to decrease noise caused by the spatial engine, objective function is choosed as the dimensionless combinations of the various shaking forces and moments, the restriction condition of which presents limiting the percent of shaking moment. Then the optimization design is investigated by the mathematical model for dynamic balance. By use of the optimization design method to a type of wobble-plate engine, the optimization process as an example is demonstrated, it shows that the optimized design method benefits to control vibration and noise on the engines and improve the performance practically and theoretically.

A new jig-shape optimization method for the high aspect ratio wing

2018 ◽  
Vol 91 (1) ◽  
pp. 124-133
Author(s):  
Zhe Yuan ◽  
Shihui Huo ◽  
Jianting Ren
Keyword(s):  
Aspect Ratio ◽  
Shape Optimization ◽  
High Aspect Ratio ◽  
Optimization Design ◽  
Design Method ◽  
Aircraft Design ◽  
Optimization Method ◽  
Attack Angle ◽  
Structural Deformation ◽  
Content Type

Purpose Computational efficiency is always the major concern in aircraft design. The purpose of this research is to investigate an efficient jig-shape optimization design method. A new jig-shape optimization method is presented in the current study and its application on the high aspect ratio wing is discussed. Design/methodology/approach First, the effects of bending and torsion on aerodynamic distribution were discussed. The effect of bending deformation was equivalent to the change of attack angle through a new equivalent method. The equivalent attack angle showed a linear dependence on the quadratic function of bending. Then, a new jig-shape optimization method taking integrated structural deformation into account was proposed. The method was realized by four substeps: object decomposition, optimization design, inversion and evaluation. Findings After the new jig-shape optimization design, both aerodynamic distribution and structural configuration have satisfactory results. Meanwhile, the method takes both bending and torsion deformation into account. Practical implications The new jig-shape optimization method can be well used for the high aspect ratio wing. Originality/value The new method is an innovation based on the traditional single parameter design method. It is suitable for engineering application.

scholarly journals Motion-Based Design of Passive Damping Devices to Mitigate Wind-Induced Vibrations in Stay Cables

Vibration ◽  
2018 ◽  
Vol 1 (2) ◽  
pp. 269-289 ◽  
Author(s):  
Javier Naranjo-Pérez ◽  
Javier Jiménez-Manfredi ◽  
Javier Jiménez-Alonso ◽  
Andrés Sáez
Keyword(s):  
Objective Function ◽  
Design Method ◽  
Optimization Method ◽  
Design Criterion ◽  
Passive Damping ◽  
Characteristic Parameters ◽  
Additional Function ◽  
Wind Action ◽  
Multi Objective ◽  
Stay Cables

Wind action can induce large amplitude vibrations in the stay cables of bridges. To reduce the vibration level of these structural elements, different types of passive damping devices are usually installed. In this paper, a motion-based design method is proposed and implemented in order to achieve the optimum design of different passive damping devices for stay cables under wind action. According to this method, the design problem is transformed into an optimization problem. Thus, its main aim is to minimize the different terms of a multi-objective function, considering as design variables the characteristic parameters of each considered passive damping device. The multi-objective function is defined in terms of the scaled characteristic parameters, one single-function for each parameter, and an additional function that checks the compliance of the considered design criterion. Genetic algorithms are considered as a global optimization method. Three passive damping devices have been studied herein: viscous, elastomeric and friction dampers. As a benchmark structure, the Alamillo bridge (Seville, Spain), is considered in order to validate the performance of the proposed method. Finally, the parameters of the damping devices designed according to this proposal are successfully compared with the results provided by a conventional design method.

The Effect of Different Optimization Methods on Robustness for Robust Optimization Design

2014 ◽  
Vol 721 ◽  
pp. 464-467
Author(s):  
Tao Fu ◽  
Qin Zhong Gong ◽  
Da Zhen Wang
Keyword(s):  
Robust Optimization ◽  
Objective Function ◽  
Robust Design ◽  
Optimization Design ◽  
Optimization Methods ◽  
Optimization Method ◽  
Design Parameters ◽  
Hybrid Particle Swarm Optimization ◽  
Design Variables ◽  
Robust Optimization Design

In view of robustness of objective function and constraints in robust design, the method of maximum variation analysis is adopted to improve the robust design. In this method, firstly, we analyses the effect of uncertain factors in design variables and design parameters on the objective function and constraints, then calculate maximum variations of objective function and constraints. A two-level optimum mathematical model is constructed by adding the maximum variations to the original constraints. Different solving methods are used to solve the model to study the influence to robustness. As a demonstration, we apply our robust optimization method to an engineering example, the design of a machine tool spindle. The results show that, compared with other methods, this method of HPSO(hybrid particle swarm optimization) algorithm is superior on solving efficiency and solving results, and the constraint robustness and the objective robustness completely satisfy the requirement, revealing that excellent solving method can improve robustness.

Shape Optimization Design of Gravity Buttress of Arch Dam Based on Asynchronous Particle Swarm Optimization Method

2014 ◽  
Vol 662 ◽  
pp. 160-163
Author(s):  
Lei Xu
Keyword(s):  
Particle Swarm Optimization ◽  
Optimization Design ◽  
Design Method ◽  
Particle Swarm ◽  
Optimization Method ◽  
Arch Dam ◽  
Swarm Optimization ◽  
Safety Coefficient ◽  
Parametric Description ◽  
Particle Swarm Optimization Method

The optimization design method was rarely used to design the gravity buttress of arch dam in the past. With this in mind, the parametric description of gravity buttress is given, and the auto-calculation of its exerting loads and the safety coefficient of anti-slide stability are realized subsequently. Then, the optimization design model of gravity buttress and the procedures of optimization design are presented using the asynchronous particle swarm optimization method. Finally, ODGB software, which is short for Optimization Design of Gravity Buttress software, is developed and verified.

Topology Optimization Design of Integral Structure of Woodworking Machine Tool

2010 ◽  
Vol 37-38 ◽  
pp. 1591-1594
Author(s):  
Zhao Xin Meng ◽  
Jun Cao ◽  
Zhi Wei Li ◽  
Jian Xin Zhao
Keyword(s):  
Topology Optimization ◽  
Machine Tool ◽  
Objective Function ◽  
Optimization Design ◽  
Design Method ◽  
Dynamic Properties ◽  
Convergence Criteria ◽  
Related Factors ◽  
Economical Efficiency ◽  
Integral Structure

In accordance with integral structure of woodworking machine tool (WMT), this paper uses the method based on topology optimization design to establish the objective function, constraints, and convergence Criteria. In the meantime, some related factors of woodworking machine tool (WMT), such as economical efficiency, stability, and dynamic properties are taken into consideration. Moreover, through analyzing an instance, the validity of design method has been demonstrated.

Improving the Robustness of Adjoint-Based Airfoil Drag Reduction Design

2013 ◽  
Vol 444-445 ◽  
pp. 259-263
Author(s):  
Yan Hong Fan
Keyword(s):  
Drag Reduction ◽  
Optimization Design ◽  
Line Search ◽  
Optimization Problem ◽  
Design Method ◽  
Optimization Method ◽  
Search Method ◽  
Linear Search

The effect of steps in the line search on the consistence of adjoint-based drag reduction of airfoil is investigated in this paper. Constant step adopted in drag reduction design usually gives different optimization results and choice of constant step often depends on designers experience and optimization problem. Bracket method is applied to automatically give the optimal step in performing drag reduction design of airfoils RAE2822 and S73613 and the consistent optimal results are obtained. The results illustrate that the linear search method can automatically find the optimal step, and overcome the restriction on choice of user-defined constant step which is used in the traditional adjoint-based optimization method. That is, it reduces the dependence of step in the drag reduction design, and improves the robustness of the adjoint-based airfoil drag reduction optimization design method.

An Optimization Design Method of Geometric Parameters of Skid Shoe Referring to Subject Weight of Marine Structures

2014 ◽  
Vol 678 ◽  
pp. 325-332
Author(s):  
Feng Yan Yang ◽  
Xiang Zhen Yan ◽  
Zheng Rong Song ◽  
Ming Wang Yang ◽  
Zi Kun Zhao ◽  
...  
Keyword(s):  
Optimization Design ◽  
Design Method ◽  
Plate Thickness ◽  
Optimization Method ◽  
Geometric Parameters ◽  
Frame Structure ◽  
Complex Method ◽  
Optimized Design ◽  
Original Design ◽  
Marine Structures

The optimization design method of geometric parameters of skid shoe which is used to subject weight of marine structures is proposed. Considering skid shoe as steel frame structure, total weight and the bearing capacity of the skid shoe are selected as optimal objectives, and geometric parameters of the skid shoe are taken as design variables. Taking the strength, stiffness, local stability of the skid shoe as the constraint conditions, multi-objectives constraints optimization model of geometric parameters is established, and solved based on complex method. According to research results, a computer program has been developed using VC language. Then geometric optimum parameters of skid shoe in service of CNOOC are analyzed by the program. The results show that optimized design decreases steel volume, steel plate thickness by 28.7%, 18.4%, respectively, compared with original design. The optimization method has a series of advantages, such as simple model, fast calculating speed, high calculation accuracy.

Intelligent Optimization Design of the Cutting Unit’s Transmission System of a Shearer Based on Robustness

2021 ◽  
pp. 2158009
Author(s):  
Hongbin Gao ◽  
Junjun Chen
Keyword(s):  
Optimization Design ◽  
Design Method ◽  
Harmonic Balance Method ◽  
Optimization Method ◽  
Transmission System ◽  
Gear Transmission ◽  
Manufacturing Cost ◽  
Tooth Width ◽  
Gear Transmission System ◽  
Cutting Unit

To improve the robustness of the shearer cutting part and reduce the manufacturing cost, in this study, the gear transmission system of a shearer’s cutting unit can be divided into three basic components: single-gear-on-one-shaft form, the planetary reduction form, and double-gears-on-one-shaft form. The dynamic differential equations of each structure are established in this study, and the volume functions of the three basic components are obtained. The characteristics of the internal excitation of the gear transmission system are analyzed, and a scheme for solving the motion parameters of each component is formulated based on the harmonic balance method. Based on the parameters, such as tooth width, tooth number, and modulus, as optimized variables, a robust optimization method minimizing the multi-parameter evaluation function, which is weighted linearly by dimensionless vibration and volume of the gear transmission system, is presented. The gear transmission system of a sample shearer’s cutting unit is optimized using the proposed method. The results show that the transmission system’s size decreases by 5.4%, the drum’s maximum torsional acceleration decreases by 17.8%, and the first gear’s maximum torsional acceleration decreases by 9.6%. Thus, we conclude that the optimum design method decreases a shearer’s manufacturing cost and decreases the cutting unit’s failure rate.

Optimization Design Method of Sealing Concrete and Ballast

2011 ◽  
Vol 368-373 ◽  
pp. 390-394
Author(s):  
Mei Liang Yang ◽  
Zhen Hai Zeng ◽  
Fang Ping Zhong ◽  
Zhen Hua Li
Keyword(s):  
Objective Function ◽  
Optimization Design ◽  
Objective Function Value ◽  
Design Method ◽  
Optimal Solution ◽  
Xiangjiang River ◽  
Economical Efficiency ◽  
Independent Variables ◽  
Unfavorable Condition ◽  
Two Independent Variables

As defined in optimization ideas, economical efficiency is the objective function, while the volume of sealing concrete and ballast, two independent variables, exerts impacts on the objective function value through economic parameters respectively. Constraints are founded according to the strength and stability requirements of sealing concrete and steel box, in the most unfavorable condition. At the last, Matlab is used to achieve optimal solution. This paper combined Xiangjiang River Grand Bridge Project in Changxiang express way and achieved good practical results.

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