A Compressible Three-Dimensional Inverse Design Method Based on the Streamline Curvature Approach and Clebsch Formulation for Radial and Mixed Flow Turbomachines

The through-flow inverse design method based on the streamline curvature approach is nowadays a widely used quasi-3-dimensional blades design method for radial and mixed flow turbomachines. The main limitation of this method is using the flow field on the mean stream surface S2,m to approximate the actual 3-dimensional flow field. Without an effective description of the periodic flow, it is impossible for this method to realize exactly the prescribed circumferentially averaged swirl rVθ. Is there any way to develop this classical through-flow inverse method to a 3-dimensional one conveniently? The answer is yes. A new compressible 3-dimensional inverse design method for radial and mixed flow turbomachines is presented in this paper. This new 3-dimensional inverse method provides a convenient and effective way to obtain the periodic flow field for the streamline curvature through-flow inverse method. Meanwhile, compared with another type of similar 3-dimensional inverse method firstly described by Tan etc. based on Stokes stream functions and Monge potential functions from the Clebsch formulation to calculate the circumferentially averaged flow and the periodic flow respectively, this new method has its own advantages. In order to assess the usefulness of the new method, four centrifugal impellers are designed under the same design specifications by four different inverse methods respectively. They are two quasi-3-dimensional streamline curvature through-flow inverse methods without and with a slip factor model, a 3-dimensional approximated inverse approach based on stream functions and Monge potential functions and the 3-dimensional inverse method presented here. The performances of the four impellers yielding from a RANS commercial solver are compared. The capabilities of the four methods to realize the target circumferentially averaged swirl are also studied.

Matching Optimization of a Mixed Flow Pump Impeller and Diffuser Based on the Inverse Design Method

Processes ◽

10.3390/pr9020260 ◽

2021 ◽

Vol 9 (2) ◽

pp. 260

Author(s):

Mengcheng Wang ◽

Yanjun Li ◽

Jianping Yuan ◽

Fareed Konadu Osman

Keyword(s):

Flow Field ◽

Design Method ◽

Inverse Design ◽

Pump Efficiency ◽

Optimization Strategy ◽

Mixed Flow ◽

Pump Impeller ◽

Circulation Distribution ◽

Inverse Design Method ◽

When considering the interaction between the impeller and diffuser, it is necessary to provide logical and systematic guidance for their matching optimization. In this study, the goal was to develop a comprehensive matching optimization strategy to optimize the impeller and diffuser of a mixed flow pump. Some useful tools and methods, such as the inverse design method, computational fluid dynamics (CFD), design of experiment, surrogate model, and optimization algorithm, were used. The matching optimization process was divided into two steps. In the first step, only the impeller was optimized. Thereafter, CFD analysis was performed on the optimized impeller to get the circulation and flow field distribution at the outlet of the impeller. In the second step of optimization, the flow field and circulation distribution at the inlet of the diffuser were set to be the same as the optimized impeller outlet. The results show that the matching optimization strategy proposed in this study is effective and can overcome the shortcomings of single-component optimization, thereby further improving the overall optimization effect. Compared with the baseline model, the pump efficiency of the optimized model at 1.2Qdes, 1.0Qdes, and 0.8Qdes is increased by 6.47%, 3.68%, and 0.82%, respectively.

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

On the role of three-dimensional inverse design methods in turbomachinery shape optimization

10.1243/0954406991522167 ◽

1999 ◽

Vol 213 (1) ◽

pp. 27-42 ◽

Cited By ~ 20

Author(s):

M Zangeneh ◽

A Goto ◽

H Harada

Keyword(s):

Flow Field ◽

Inverse Method ◽

Design Method ◽

Three Dimensional ◽

Design Guidelines ◽

Secondary Flows ◽

Inverse Design ◽

Vaned Diffuser ◽

Oil Flow ◽

The application of a three-dimensional (3D) inverse design method in which the blade geometry is computed for a specified distribution of circulation to the design of turbomachinery blades is explored by using two examples. In the first instance the method is applied to the design of radial and mixed flow impellers to suppress secondary flows. Based on our understanding of the fluid dynamics of the flow in the impeller, simple guidelines are developed for input specification of the inverse method in order to systematically design impellers with suppressed secondary flows and a more uniform exit flow field. In the second example the method is applied to the design of a vaned diffuser. Again based on the understanding of the detailed flow field in the diffuser obtained by using 3D viscous calculations and oil flow visualizations, simple design guidelines are developed for input specification to the inverse method in order to suppress corner separation. In both cases the guidelines are verified numerically and in the case of the diffuser further experimental validation is presented.

Suppression of Secondary Flows in a Mixed-Flow Pump Impeller by Application of 3D Inverse Design Method: Part 1 — Design and Numerical Validation

Volume 1: Turbomachinery ◽

10.1115/94-gt-045 ◽

1994 ◽

Author(s):

M. Zangeneh ◽

A. Goto ◽

T. Takemura

Keyword(s):

Flow Field ◽

Design Method ◽

Secondary Flows ◽

Inverse Design ◽

Experimental Comparison ◽

Suction Surface ◽

Mixed Flow ◽

Pump Impeller ◽

Inverse Design Method ◽

This paper describes the design of the blade geometry of a medium specific speed mixed flow pump impeller by using a 3D inverse design method in which the blade circulation (or rVθ) is specified. The design objective being the reduction of impeller exit flow non-uniformity by reducing the secondary flows on the blade suction surface. The paper describes in detail the aerodynamic critria used for the suppression of secondary flows with reference to the loading distribution and blade stacking condition used in the design. The flow through the designed impeller is computed by Dawes viscous code, which indicates that the secondary flows are well suppressed on the suction surface. Comparison between the predicted exit flow field of the inverse designed impeller and a corresponding conventional impeller indicates that the suppression of secondary flows has resulted in substantial improvement in the exit flow field. Experimental comparison of the flow fields inside and at exit from the conventional and the inverse designed impeller is made in part 2 of the paper.

Suppression of Secondary Flows in a Mixed-Flow Pump Impeller by Application of Three-Dimensional Inverse Design Method: Part 1—Design and Numerical Validation

Journal of Turbomachinery ◽

10.1115/1.2836700 ◽

1996 ◽

Vol 118 (3) ◽

pp. 536-543 ◽

Cited By ~ 42

Author(s):

M. Zangeneh ◽

A. Goto ◽

T. Takemura

Keyword(s):

Flow Field ◽

Design Method ◽

Three Dimensional ◽

Secondary Flows ◽

Inverse Design ◽

Suction Surface ◽

Mixed Flow ◽

Pump Impeller ◽

Inverse Design Method ◽

This paper describes the design of the blade geometry of a medium specific speed mixed flow pump impeller by using a three-dimensional inverse design method in which the blade circulation (or rVθ) is specified. The design objective is the reduction of impeller exit flow nonuniformity by reducing the secondary flows on the blade suction surface. The paper describes in detail the aerodynamic criteria used for the suppression of secondary flows with reference to the loading distribution and blade stacking condition used in the design. The flow through the designed impeller is computed by Dawes’ viscous code, which indicates that the secondary flows are well suppressed on the suction surface. Comparison between the predicted exit flow field of the inverse designed impeller and a corresponding conventional impeller indicates that the suppression of secondary flows has resulted in substantial improvement in the exit flow field. Experimental comparison of the flow fields inside and at exit from the conventional and the inverse designed impeller is made in Part 2 of the paper.

Dual Point Redesign of Axial Turbines Using a Viscous Inverse Design Method

Volume 7: Turbomachinery, Parts A and B ◽

10.1115/gt2009-59707 ◽

2009 ◽

Author(s):

Benedikt Roidl ◽

Wahid Ghaly

Keyword(s):

Inverse Method ◽

Stokes Equations ◽

Design Method ◽

Single Point ◽

Accurate Solution ◽

Inverse Design ◽

Suction Surface ◽

Pressure Distributions ◽

Wide Range ◽

A new dual-point inverse blade design method was developed and applied to the redesign of a highly loaded transonic vane, the VKI-LS89, and the first 2.5 stages of a low speed subsonic turbine, the E/TU-4 4-stage turbine that is built and tested at the university of Hannover, Germany. In this inverse method, the blade walls move with a virtual velocity distribution derived from the difference between the current and the target pressure distributions on the blade surfaces at both operating points. This new inverse method is fully consistent with the viscous flow assumption and is implemented into the time accurate solution of the Reynolds-Averaged Navier-Stokes equations. An algebraic Baldwin-Lomax turbulence model is used for turbulence closure. The mixing plane approach is used to couple the stator and rotor regions. The dual-point inverse design method is then used to explore the effect of different choices of the pressure distributions on the suction surface of one or more rotor/stator on the blade/stage performance. The results show that single point inverse design resulted in a local performance improvement whereas the dual point design method allowed for improving the performance of both VKI-LS89 vane and E/TU-4 2.5 stage turbines over a wide range of operation.

Design of the Blade Geometry of Swept Transonic Fans by 3D Inverse Design

Volume 6: Turbo Expo 2003, Parts A and B ◽

10.1115/gt2003-38770 ◽

2003 ◽

Cited By ~ 7

Author(s):

H. Watanabe ◽

M. Zangeneh

Keyword(s):

Inverse Method ◽

Design Method ◽

Pressure Ratio ◽

Inverse Design ◽

Specific Work ◽

Design Practice ◽

Blade Loading ◽

Inverse Design Method ◽

Transonic Fan ◽

Blade Geometry

The application of sweep in the design of transonic fans has been shown to be an effective method of controlling the strength and position of the shock wave at the tip of transonic fan rotors, and the control of corner separations in stators. In rotors sweep can extend the range significantly. However, using sweep in conventional design practice can also result in a change in specific work and therefore pressure ratio. As a result, laborious iterations are required in order to recover the correct specific work and pressure ratio. In this paper, the blade geometry of a transonic fan is designed with sweep using a 3D inverse design method in which the blade geometry is computed for a specified distribution of blade loading. By comparing the resulting flow field in the conventionally and inversely designed swept rotors, it is shown that it is possible to apply sweep without the need to iterate to maintain pressure ratio and specific work when using the inverse method.

Redesign of a Highly Loaded Transonic Turbine Nozzle Blade Using a New Viscous Inverse Design Method

Volume 6: Turbo Expo 2007, Parts A and B ◽

10.1115/gt2007-27430 ◽

2007 ◽

Author(s):

Kasra Daneshkhah ◽

Wahid Ghaly

Keyword(s):

Inverse Method ◽

Design Method ◽

Guide Vane ◽

Accurate Solution ◽

Inverse Design ◽

Arbitrary Lagrangian Eulerian ◽

Pressure Distributions ◽

Transonic Turbine ◽

Inverse Design Method ◽

Highly Loaded

The redesign of VKI-LS89 turbine vane, which is typical of a highly loaded transonic turbine guide vane is presented. The redesign is accomplished using a new inverse design method where the blade walls move with a virtual velocity distribution derived from the difference between the current and the target pressure distributions on the blade surfaces. This new inverse method is fully consistent with the viscous flow assumption and is implemented into the time accurate solution of the Reynolds-Averaged Navier-Stokes (RANS) equations that are expressed in an arbitrary Lagrangian-Eulerian (ALE) form to account for mesh movement. A cell-vertex finite volume method is used to discretize the equations in space; time accurate integration is obtained using dual time stepping. An algebraic Baldwin-Lomax model is used for turbulence closure. The flow analysis formulation is first assessed against the LS89 experimental data. The inverse formulation that is implemented in the same code, is also assessed for its robustness and accuracy, by inverse designing the LS89 original geometry through running the inverse method with the original LS89 pressure distributions as target distributions but starting from an arbitrary geometry. The inverse design method is then used to redesign the LS89 using an arbitrary pressure distributions at a subsonic and a transonic outflow condition and the results are interpreted in terms of the blade overall aerodynamic performance.

AN INVERSE DESIGN METHOD FOR METAMATERIAL SHRINKING DEVICE

Modern Physics Letters B ◽

10.1142/s0217984913501820 ◽

2013 ◽

Vol 27 (25) ◽

pp. 1350182 ◽

Author(s):

TINGHUA LI ◽

MING HUANG ◽

JINGJING YANG ◽

JIA ZENG ◽

JIN LU

Keyword(s):

Inverse Method ◽

Effective Medium Theory ◽

Design Method ◽

Transformation Function ◽

Inverse Design ◽

Medium Theory ◽

Material Parameters ◽

Full Wave ◽

Traditional Design ◽

In this paper, an inverse method to determine the parameters of metamaterial shrinking device is developed. Different from the traditional design method, of which the transformation function must be known in advance, this method allows us to directly obtain material parameters of device without any knowledge of the corresponding transformation function. Moreover, to further remove the inhomogeneity and anisotropy of material parameters, layered device composed of only homogeneous and isotropic materials is presented based on effective medium theory. The validity of such a method and shrinking effect of designed device are confirmed by full-wave simulations.

Volume 1: Aircraft Engine; Marine; Turbomachinery; Microturbines and Small Turbomachinery ◽

Turbomachinery Blade Design Using 3-D Inverse Design Method, CFD and Optimization Algorithm

10.1115/2001-gt-0358 ◽

2001 ◽

Cited By ~ 11

Author(s):

Kosuke Ashihara ◽

Akira Goto

Keyword(s):

Simulated Annealing ◽

Optimization Algorithm ◽

Design Method ◽

Three Dimensional ◽

Inverse Design ◽

Mixed Flow ◽

Specific Speed ◽

Inverse Design Method ◽

Suction Performance ◽

An optimization approach for improving turbomachinery performance was proposed based on a three-dimensional inverse design method, a Computational Fluid Dynamics (CDF) and optimization algorithm. By combining the three-dimensional inverse design method and CFD predictions, the blade loading parameters which is the major inputs for the three-dimensional inverse design method were treated as design variables and the impeller performance predicted by CFD was treated as an objective function of the optimization problem. Firstly, to clarify the effects of optimization algorithm, mixed-flow pump impellers (Ns400), with a specific speed of 400 (m3/min,m,min−1) or 0.155 (non-dimensional), were optimized to improve the impeller efficiency by using several optimization algorithm. From these results, it was confirmed that turbomachinery optimization using the three-dimensional inverse design method is a multi-peak problem and it is essential to use exploratory techniques such as Simulated Annealing. Then, a mixed-flow pump impeller (Ns1350), with a specific speed of 1350 (m3/min,m,min−1) or 0.523 (non-dimensional), was optimized to improve the impeller efficiency with constraints for suction performance by Simulated Annealing. Reasonably high efficiency and high suction performance were confirmed by comparing the CFD results with those for the previous design which employed manual optimization.

Influence of Spanwise Distribution of Impeller Exit Circulation on Optimization Results of Mixed Flow Pump

Applied Sciences ◽

10.3390/app11020507 ◽

2021 ◽

Vol 11 (2) ◽

pp. 507

Author(s):

Mengcheng Wang ◽

Yanjun Li ◽

Jianping Yuan ◽

Fareed Konadu Osman

Keyword(s):

Design Method ◽

Internal Flow ◽

Inverse Design ◽

Pump Efficiency ◽

Mixed Flow ◽

Baseline Model ◽

Pump Impeller ◽

First Case ◽

Inverse Design Method ◽

The spanwise distribution of impeller exit circulation (SDIEC) has an important influence on the performance of the impeller. To quantitatively study the influence of SDIEC on optimization results, a comprehensive optimization system composed of the computational fluid dynamics, inverse design method, design of experiment, surrogate model, and optimization algorithm was used to optimize a mixed flow pump impeller in two different cases. In the first case, the influence of SDIEC was ignored, while in the second case, the influence of SDIEC was considered. The result shows that the optimization upper limit can be further improved when the influence of SDIEC is considered in the optimization process. The pump efficiency of the preferred optimized impeller F1 obtained in the first case at 1.2Qdes, 1.0Qdes, and 0.8Qdes are increased by 6.48%, 2.41%, and 0.06%, respectively, over the baseline model. Moreover, the pump efficiency of the preferred optimized impeller S2 obtained in the second case further increased by 0.76%, 1.24%, and 1.21%, respectively, over impeller F1. Furthermore, the influence of SDIEC on the performance of the mixed flow pump is clarified by a comparative analysis of the internal flow field.