Suppression of secondary flows in a centrifugal impeller by optimisation design

2020 ◽  
Vol 37 (9) ◽  
pp. 3023-3044
Author(s):  
Xing Xie ◽  
Zhenlin Li ◽  
Baoshan Zhu ◽  
Hong Wang
Keyword(s):  
Control Parameter ◽  
Aerodynamic Performance ◽  
Secondary Flows ◽  
Inverse Design ◽  
Design System ◽  
Centrifugal Impeller ◽  
Cfd Analysis ◽  
Blade Loading ◽  
Content Type ◽  
Multi Objective

Purpose The purpose of this study is to suppress secondary flows and improve aerodynamic performance of a centrifugal impeller. Design/methodology/approach A multi-objective optimisation design system was described. The optimization design system was composed of a three-dimensional (3D) inverse design, multi-objective optimisation and computational fluid dynamics (CFD) analysis. First, the control parameter ΔCp for the secondary flows was derived and selected as the optimisation objective. Then, aimed at minimising ΔCp, a 3D inverse design for impellers with different blade loading distributions and blade lean angles was completed and multi-objective optimisation was conducted. Lastly, the improvement in the distribution of secondary flows and aerodynamic performance of the optimal impeller was demonstrated by CFD analysis. Findings The study derived the control parameter ΔCp for the secondary flows. ΔCp can indicate the distribution of secondary flows both near the blade pressure and suction surfaces. As ΔCp decreased, secondary flows decreased. The blade loading distribution with fore maximum blade loading at the shroud and aft maximum blade loading at the hub, coupled with a small negative blade lean angle, could help suppress secondary flows and improve aerodynamic efficiency. Originality/value A direct control method on internal flow field characteristic-secondary flows by optimisation design was proposed for a centrifugal impeller. The impeller optimisation design process saves time by avoiding substantial CFD sample calculations.

Hydrodynamic Design System for Pumps Based on 3-D CAD, CFD, and Inverse Design Method

2002 ◽  
Vol 124 (2) ◽  
pp. 329-335 ◽  
Author(s):  
Akira Goto ◽  
Motohiko Nohmi ◽  
Takaki Sakurai ◽  
Yoshiyasu Sogawa
Keyword(s):  
Computer Aided Design ◽  
High Performance ◽  
Design Method ◽  
High Reliability ◽  
Secondary Flows ◽  
System Structure ◽  
Inverse Design ◽  
Design System ◽  
Centrifugal Impeller ◽  
Inverse Design Method

A computer-aided design system has been developed for hydraulic parts of pumps including impellers, bowl diffusers, volutes, and vaned return channels. The key technologies include three-dimensional (3-D) CAD modeling, automatic grid generation, CFD analysis, and a 3-D inverse design method. The design system is directly connected to a rapid prototyping production system and a flexible manufacturing system composed of a group of DNC machines. The use of this novel design system leads to a drastic reduction of the development time of pumps having high performance, high reliability, and innovative design concepts. The system structure and the design process of “Blade Design System” and “Channel Design System” are presented. Then the design examples are presented briefly based on the previous publications, which included a centrifugal impeller with suppressed secondary flows, a bowl diffuser with suppressed corner separation, a vaned return channel of a multistage pump, and a volute casing. The results of experimental validation, including flow fields measurements, were also presented and discussed briefly.

Multi-objective optimization design of a centrifugal impeller considering both aerodynamic efficiency and structural machinability

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Xing Xie ◽  
Zhenlin Li ◽  
Baoshan Zhu ◽  
Hong Wang
Keyword(s):  
Optimization Design ◽  
Inverse Design ◽  
Centrifugal Impeller ◽  
Multi Objective Optimization ◽  
Blade Angle ◽  
Aerodynamic Efficiency ◽  
Blade Loading ◽  
Content Type ◽  
Wrap Angle ◽  
Blade Wrap Angle

Purpose This study aims to complete the optimization design of a centrifugal impeller with both high aerodynamic efficiency and good structural machinability. Design/methodology/approach First, the design parameters were derived from the blade loading distribution and the meridional geometry in the impeller three-dimensional (3D) inverse design. The blade wrap angle at the middle span surface and the spanwise averaged blade angle at the blade leading edge obtained from inverse design were chosen as the machinability objectives. The aerodynamic efficiency obtained by computational fluid dynamics was selected as the aerodynamic performance objective. Then, using multi-objective optimization with the optimal Latin hypercube method, quadratic response surface methodology and the non-dominated sorting genetic algorithm, the trade-off optimum impellers with small blade wrap angles, large blade angles and high aerodynamic efficiency were obtained. Finally, computational fluid dynamics and computer-aided manufacturing were performed to verify the aerodynamic performance and structural machinability of the optimum impellers. Findings Providing the fore maximum blade loading distribution at both the hub and shroud for the 3D inverse design helped to promote the structural machinability of the designed impeller. A straighter hub coupled with a more curved shroud also facilitated improvement of the impeller’s structural machinability. The preferred impeller was designed by providing both the fore maximum blade loading distribution at a relatively straight hub and a curved shroud for 3D inverse design. Originality/value The machining difficulties of the designed high-efficiency impeller can be reduced by reducing blade wrap angle and enlarging blade angle at the beginning of impeller design. It is of practical value in engineering by avoiding the follow-up failure for the machining of the designed impeller.

Improving a Vaned Diffuser for a Given Centrifugal Impeller by 3D Inverse Design

2002 ◽  
Author(s):  
Mehrdad Zangeneh ◽  
Damian Vogt ◽  
Christian Roduner
Keyword(s):  
Flow Field ◽  
Viscous Flow ◽  
Centrifugal Compressor ◽  
Inverse Method ◽  
Flow Distribution ◽  
Inverse Design ◽  
Centrifugal Impeller ◽  
Design Code ◽  
Vaned Diffuser ◽  
Blade Loading

In this paper the application of 3D inverse design code TURBOdesign−1 to the design of the vane geometry of a centrifugal compressor vaned diffuser is presented. For this study the new diffuser is designed to match the flow leaving the conventional impeller, which is highly non-uniform. The inverse method designs the blade geometry for a given specification of thickness and blade loading distribution. The paper describes the choice of loading distribution used in the design as well as the influence of the diffuser inlet flow distribution on the vane geometry and flow field. The flow field in the new diffuser is analysed by a 3D viscous flow code and the result is compared to that of the conventional diffuser. Finally the results of testing the stage performance of the new diffuser is compared with that of the conventional stage.

Aerodynamic Analysis and Multi-Objective Optimization Design of a High Pressure Ratio Centrifugal Impeller

2014 ◽  
Author(s):  
Zhendong Guo ◽  
Zhiming Zhou ◽  
Liming Song ◽  
Jun Li ◽  
Zhenping Feng
Keyword(s):  
Data Mining ◽  
High Pressure ◽  
Pressure Ratio ◽  
Differential Evolution Algorithm ◽  
Aerodynamic Performance ◽  
Centrifugal Impeller ◽  
Tip Leakage Flow ◽  
Pareto Solutions ◽  
Multi Objective ◽  
High Pressure Ratio

The design of high pressure ratio impellers is a challenging task. SRV2-O, a typical high pressure ratio centrifugal impeller is selected for the research. A good understanding of flow characteristics in the passage of SRV2-O is obtained by using 3D Reynolds-Averaged Navier-Stokes (RANS) solutions upon numerical validation. It confirms that tip leakage flow and shock wave boundary layer interactions produce the primary energy loss in this transonic impeller. A 3D multi-objective aerodynamic optimization and data mining method named BMOE is presented and programmed by integrating a self-adaptive multi-objective differential evolution algorithm SMODE, 3D blade parameterization method based on non-uniformed B-Spline, RANS solver technique and self-organization map (SOM) based data mining technique. Using BMOE, multi-objective aerodynamic design optimization and data mining is performed for SRV2-O. 14 Pareto solutions are obtained for maximizing isentropic efficiency and total pressure ratio of the impeller. Three typical Pareto solutions, Design A with the highest efficiency, Design B with the higher efficiency and larger pressure ratio and Design C with the maximum pressure ratio, are analyzed. Detailed analysis indicates that the aerodynamic performance of optimized designs is greatly improved. Furthermore, by SOM-based data mining on optimization results, trade-off relation between objective functions and parameter influence mechanism on impeller aerodynamic performance are visualized and explored.

The Optimization of a Centrifugal Impeller Based on a New Multi-Objective Evolutionary Strategy

2016 ◽  
Author(s):  
Xiaojian Li ◽  
Yijia Zhao ◽  
Zhengxian Liu ◽  
Hua Chen
Keyword(s):  
Pressure Ratio ◽  
Aerodynamic Performance ◽  
Evolutionary Strategy ◽  
Centrifugal Impeller ◽  
Nsga Ii ◽  
Multi Objective ◽  
Compressor Performance ◽  
Aero Engines ◽  
Total Pressure Ratio ◽  
Petrochemical Engineering

Centrifugal compressors with high aerodynamic performance are widely used in turbochargers, aero-engines and petrochemical engineering. The impeller is the core component and plays a key role in determining the compressor performance. This paper reports the optimisation of the aerodynamic performance of an industrial centrifugal impeller by a multi-objective evolutionary strategy. Firstly the 3-D modeling method for parameterisation of impeller’s geometry was described. Secondly the traditional NSGA-II method was modified to improve its ability and efficiency. Employed CFD code was first validated using the experimental data of an existing impeller. The optimisation was applied to the industrial centrifugal impeller through a two-step optimization process to allow for significant variations of the impeller geometry and speedy finding of the optimum. The optimisation was completed within 53 hours on a workstation with two 24-core processors (Xeon(R) E5-2670 v3 2.3GHz). The results indicated that the isentropic efficiency of the impeller increased by 5.3 percents and the total pressure ratio by 20.5 percents at design condition.

Effects of Unsteady Wakes on the Secondary Flows in the Linear T106 Turbine Cascade

2013 ◽  
Author(s):  
Roberto Ciorciari ◽  
Ilker Kirik ◽  
Reinhard Niehuis
Keyword(s):  
Boundary Layer ◽  
High Pressure ◽  
Aerodynamic Performance ◽  
High Flow ◽  
Secondary Flows ◽  
Experimental Results ◽  
Pressure Gradients ◽  
Turbine Cascade ◽  
Blade Loading ◽  
Relative Differences

In modern low pressure turbines the efforts to increase aerodynamic blade loading by increasing blade pitch and optimising midspan performance in order to reduce weight and complexity can produce increased losses in the endwall region. Airfoils of high flow turning and high pressure gradients between the blades generate strong secondary flows which impair the global aerodynamic performance of the blades. In addition, the unsteady incoming wakes take influence on transition phenomena on the blade surfaces and the inlet boundary layer, and consequently affect the development and the evolution of the secondary flows. In this paper the T106 cascade is used to identify the effect of unsteady wakes on the development of secondary flows in a turbine cascade. Numerical and experimental results are compared at different flux coefficients and Strouhal numbers, the relative differences and similarities are analysed.

Patch size setup and performance/cost trade-offs in multi-objective EM-driven antenna optimization using sequential domain patching

2017 ◽  
Vol 34 (4) ◽  
pp. 1070-1081
Author(s):  
Slawomir Koziel ◽  
Adrian Bekasiewicz
Keyword(s):  
Control Parameter ◽  
Computational Cost ◽  
Design Procedure ◽  
Simulation Models ◽  
Multi Objective Optimization ◽  
Computationally Efficient ◽  
Content Type ◽  
Multi Objective ◽  
Trade Offs ◽  
And Performance

Purpose This paper aims to assess control parameter setup and its effect on computational cost and performance of deterministic procedures for multi-objective design optimization of expensive simulation models of antenna structures. Design/methodology/approach A deterministic algorithm for cost-efficient multi-objective optimization of antenna structures has been assessed. The algorithm constructs a patch connecting extreme Pareto-optimal designs (obtained by means of separate single-objective optimization runs). Its performance (both cost- and quality-wise) depends on the dimensions of the so-called patch, an elementary region being relocated in the course of the optimization process. The cost/performance trade-offs are studied using two examples of ultra-wideband antenna structures and the optimization results are compared to draw conclusions concerning the algorithm robustness and determine the most advantageous control parameter setups. Findings The obtained results indicate that the investigated algorithm is very robust, i.e. its performance is weakly dependent on the control parameters setup. At the same time, it is found that the most suitable setups are those that ensure low computational cost, specifically non-uniform ones generated on the basis of sensitivity analysis. Research limitations/implications The study provides recommendations for control parameter setup of deterministic multi-objective optimization procedure for computationally efficient design of antenna structures. This is the first study of this kind for this particular design procedure, which confirms its robustness and determines the most suitable arrangement of the control parameters. Consequently, the presented results permit full automation of the surrogate-assisted multi-objective antenna optimization process while ensuring its lowest possible computational cost. Originality/value The work is the first comprehensive validation of the sequential domain patching algorithm under various scenarios of its control parameter setup. The considered design procedure along with the recommended parameter arrangement is a robust and computationally efficient tool for fully automated multi-objective optimization of expensive simulation models of contemporary antenna structures.

Effects of Unsteady Wakes on the Secondary Flows in the Linear T106 Turbine Cascade

2014 ◽  
Vol 136 (9) ◽  
Author(s):  
Roberto Ciorciari ◽  
Ilker Kirik ◽  
Reinhard Niehuis
Keyword(s):  
Boundary Layer ◽  
High Pressure ◽  
Aerodynamic Performance ◽  
High Flow ◽  
Secondary Flows ◽  
Experimental Results ◽  
Pressure Gradients ◽  
Turbine Cascade ◽  
Blade Loading ◽  
Relative Differences

In modern low pressure turbines the efforts to increase aerodynamic blade loading by increasing blade pitch and optimizing midspan performance in order to reduce weight and complexity can produce increased losses in the endwall region. Airfoils of high flow turning and high pressure gradients between the blades generate strong secondary flows which impair the global aerodynamic performance of the blades. In addition, the unsteady incoming wakes take influence on transition phenomena on the blade surfaces and the inlet boundary layer, and consequently affect the development and the evolution of the secondary flows. In this paper, the T106 cascade is used to identify the effect of unsteady wakes on the development of secondary flows in a turbine cascade. Numerical and experimental results are compared at different flux coefficients and Strouhal numbers, the relative differences and similarities are analyzed.

Two Schemes of Multi-Objective Aerodynamic Optimization for Centrifugal Impeller Using Response Surface Model and Genetic Algorithm

2010 ◽  
Author(s):  
Xiaomin Liu ◽  
Wenbin Zhang
Keyword(s):  
Genetic Algorithm ◽  
Surrogate Model ◽  
Optimization Design ◽  
Aerodynamic Performance ◽  
Centrifugal Impeller ◽  
Surface Model ◽  
Aerodynamic Optimization ◽  
Optimization Scheme ◽  
Impeller Blade ◽  
Multi Objective

This paper presents two schemes of multi-objective aerodynamic optimization design for centrifugal impeller blade. One is genetic algorithm(GA) combined with a commercial computational fluid dynamics(CFD) software, and the other is GA combined with the surrogate model. The two schemes are respectively applied to multi-objective optimization for the same centrifugal impeller blade. For multi-objective genetic algorithm(MOGA), non-uniform mutation and Pareto ranking and fitness-sharing technique are used to obtain fast convergence speed and good capability to search the Pareto front of GA. For the surrogate model based on radial basis function(RBF), design of experiments(DOE) technology is adopted to select samples. The parameters and weight coefficients in the surrogate model are solved by GA instead of traditional least square method. According to the geometrical feature of centrifugal impeller, a three-dimensional reconstruction method for the blade shape based on non-uniform rational B-spline(NURBS) is introduced. The numerical simulation is used to evaluate the aerodynamic performance of the optimal and initial impeller. The computational results show that the aerodynamic performance of impellers designed by both optimization schemes is improved to some extent. At the same time, the main reasons for the improvement in aerodynamic performance of the optimal impeller are revealed. For the optimal impellers, the isentropic efficiency and total pressure ratio are increased by about 1.0% and 3.0% respectively. Through comparison of two schemes applied to the centrifugal impeller optimization design, it is found that the computational performance of the second optimization scheme is superior to that of the first optimization scheme.

Numerical Investigation of Blade Profile Effects on Aerodynamic Performance of Ultra-Highly Loaded Turbine Cascades

2004 ◽  
Author(s):  
Hoshio Tsujita ◽  
Shimpei Mizuki ◽  
Atsumasa Yamamoto
Keyword(s):  
Three Dimensional ◽  
Simple Algorithm ◽  
Aerodynamic Performance ◽  
Secondary Flows ◽  
Turbine Cascade ◽  
Blade Profile ◽  
Suction Surface ◽  
Blade Loading ◽  
Turbine Cascades ◽  
Highly Loaded

The increase of blade loading of a turbine cascade makes it possible to reduce the number of blades and stages, and consequently to decrease both the weights and the costs for manufacturing and maintenance. However, strong secondary flows appear in such highly loaded turbine cascades due to the high turning angles which reduce the efficiency. In the present study, the effects of blade profile on the aerodynamic performance of a stationary linear ultra-highly loaded turbine cascade (UHLTC), which will be used for the future gas turbine engines of hypersonic transport, were investigated numerically. The two and three dimensional calculations were carried out for the flows within the three types of UHLTC, which have the same design turning angle of 160 degree and with the different profile of the suction surface. The first was named ‘Original’. The others were ‘Up’ and ‘Down’ which had the longer length of suction surface and the shorter one than that of the Original, respectively. In the present computational code, the governing equations for the incompressible turbulent flow which include the standard k-ε turbulence model were solved by the SIMPLE algorithm. The convection term was estimated by the third order upwind difference scheme. The present computed results were examined by comparing with the experimental results. The total pressure loss, the profile loss, the secondary loss and the blade loading distribution for the three types of UHLTC were compared in detail with each other to reveal the effect of blade profile on the aerodynamic performance of UHLTC.

Sign in / Sign up

Export Citation Format

Share Document