Methodology for Aerodynamic Design and Optimization of Axial Rotor Blade Based on the Effects of Sweep and Dihedral (original) (raw)

IRJET- Axial Flow Turbine Aerodynamic Shape Design optimization

IRJET, 2020

This paper presents an axial turbine blade metamodeling (surrogate modeling) process performing the axial turbine blade aerodynamic shape design optimization, based on the axial turbine design parameters. This modeling technique is applied on the rotor blade of the axial flow turbine stage, working through the small turbojet engine JETCAT P 200. This metamodel consists of 140 turbine stage CFD models, generated by varying the inlet and exit meanline airfoil cone angles of the rotor blade within certain range using the integrated random sampling function in the commercial program MATLAB. The flow field of these models is solved numerically by the commercial CFD code ANSYS CFX. The objective of these optimization process is to study the effect of blade profile shape change on the different aerothermodynamic performance parameters of the axial turbine stage. A special code is designed on MATLAB to collect the resultant data of great concern from the pre-solved CFD models. The CFD generated data is interpolated and presented in graphs using the integrated curve fitting APPS in MATLAB to study the relationship between the turbine blade profile change and the axial turbine stage working conditions, which is the Surrogate Modeling. The presented parameters are the total-total isentropic efficiency, exit stage total pressure, turbine work, engine thrust, mass flow rate through the turbine stage. A multi objective optimization using the Surrogate Model generated data to determine the optimum working point according to the requirements of the present case study. 2 Introduction At the end of the design cycle, it becomes essential to optimize the design according to the requirements of the working application. In the field of axial flow turbine shape design optimization, there is no direct relationship between the turbine shape design parameters and the flow working conditions (cannot be represented by a direct equation). The mass, momentum and energy transfer of the flow through the axial flow turbine are governed by a non-linear 2 nd order partial differential equations (could'not be solved analytically), so, the flow field around the axial turbine blades needs to be evaluated numerically using the CFD techniques. In the present case, there is no direct relationship between i.e. turbine total-total efficiency and the blade profile shape parameters, so, using the conventional optimization algorithms like Genetic Algorithm (GA) are so difficult to be applied. The optimization process using the conventional GA needs designing of special codes of high-level language which is out of scope of most of the turbomachinery designers and takes much time to be achieved. Surrogate model or metamodel will be efficient to be used here, which is called the Aerodynamic design optimization (ADO). The first step of performing this technique is to design a CFD model representing the studied axial turbine stage using its dimensions and working conditions. The flow parameters (objective) are obtained numerically by solving the turbine stage flow-field over the real case working domain using the commercial CFD code ANSYS CFX. After validating the results of the designed CFD model, it becomes the High-Fidelity Model. The domain of the experiment should be designed with a fair number of CFD models, and the response surface is generated for the flow parameters of great concern separately. The response surface is a three axes graph, in which, the independent parameters are represented on the x and y axes, while the z axis represents the resultant data from the CFD code for the objective parameter. The response surface becomes the direct mathematical relationship between the independent variable and flow parameters. The mathematical equation of the response surface is now easy to be obtained using the modern programs like i.e. MATLAB or EXCEL. A check step here is essential by solving more number of high-fidelity models and comparing its results with those are predicted using the generated response surface. A new phase of the optimization process is ready to be achieved, the role of the high-fidelity model (the CFD work) is finished. The response surface becomes the main model to predict the needed turbine performance parameters data for any proposed model over the designed domain of experiment and for any further optimization work [1]. The Aerodynamic Design Optimization is recently increased due to the increasing demands for optimizing complicated geometries like studying the different turbomachinery blade profiles, achieving improved operating conditions, and satisfying several design and market requirements. Since the aerodynamic design works mainly depend on numerical simulation computer codes, the use of ADO is now strongly preferred because of the increasing capabilities of modern super computers.

Numerical and Experimental Study of the Blade Profile of a Savonius Type Rotor Implementing a Multi-Blade Geometry

Applied Sciences, 2021

In the present study, the implementation of multi-blade profiles in a Savonius rotor was evaluated in order to increase the pressure in the blade’s intrados and, thus, decrease motion resistance. The geometric proportions of the secondary element were determined, which maximized the rotor’s performance. For this, the response surface methodology was used through a full factorial experimental design and a face-centered central composite design, consisting of three factors, each with three levels. The response variable that was sought to be maximized was the power coefficient (CP), which was obtained through the numerical simulation of the geometric configurations resulting from the different treatments. All geometries were studied under the same parameters and computational fluid dynamics models through the ANSYS Fluent software. The results obtained through both experimental designs showed a difference of only 1.06% in the performance estimates using the regression model and 3.41% w...

Numerical Optimization of the Blade Profile of a Savonius Type Rotor Using the Response Surface Methodology

Sustainability

The present study aims to numerically determine the geometric proportions that maximize the performance of a Savonius rotor with a split Bach blade profile. For this, the response surface methodology was used through a full factorial experimental design, comprised of four factors corresponding to the width (C) and length (L) of the overlap, and the eccentricity (E) and radius (R) of the blade, which define the geometry of the rotor. The models built from the different treatments of the experimental designs were analyzed using computational simulations in order to obtain the power coefficient (CP), considered as the response variable. The same parameters and models of computational fluid dynamics were used to analyze each geometry through the ANSYS Fluent software. The analysis of the obtained results showed that there is a great interaction among the evaluated factors, which demonstrates the importance of analyzing them together. The results obtained with the full factorial experime...

Blade Profile Optimization of Kaplan Turbine Using CFD Analysis

2020

Utilization of hydro-power as renewable energy source is of prime importance in the world now. Hydropower energy is available in abundant in form of falls, canals rivers, dams etc. It means, there are various types of sites with different parameters like flow rate, heads, etc. Depending upon the sites, water turbines are designed and manufactured to avail hydro-power energy. Low head turbines on runof-river are widely used for the purpose. Low head turbines are classified as reaction turbines. For runof river, depending upon the variety of site data, low head Kaplan turbines are selected, designed and manufactured. For any given site requirement, it becomes very essential to design the turbine runner blades through optimization of the CAD model of blades profile. This paper presents the optimization technique carried out on a complex geometry of blade profile through static and dynamic computational analysis. It is used through change of the blade profile geometry at five different angles in the 3D (Three Dimensional) CAD model. Blade complex geometry and design have been developed by using the coordinates point system on the blade in PRO-E /CREO software. Five different blade models are developed for analysis purpose. Based on the flow rate and heads, blade profiles are analyzed using ANSYS software to check and compare the output results for optimization of the blades for improved results which show that by changing blade profile angle and its geometry, different blade sizes and geometry can be optimized using the computational techniques with changes in CAD models.

Computational fluid dynamics analysis of a modified Savonius rotor and optimization using response surface methodology

Wind Engineering, 2017

This article aims to present a two-dimensional parametric analysis of a modified Savonius wind turbine using computational fluid dynamics. The effects of three independent parameters of the rotor, namely, shape factor, overlap ratio, and tip speed ratio on turbine performance were studied and then optimized for maximum coefficient of performance using response surface methodology. The rotor performance was analyzed over specific domains of the parameters under study, and three-variable Box-Behnken design was used for design of experiment. The specific parametric combinations as per design of experiment were simulated using ANSYS Fluent®, and the response variable, coefficient of performance (Cp), was calculated. The sliding mesh model was utilized, and the flow was simulated using Shear Stress Transport (SST) k − ω model. The model was validated using past experimental results and found to predict parametric effects accurately. Minitab® and ReliaSoft DOE++® were used to develop regr...

Study on the design of propeller blade sections using the optimization algorithm

Journal of Marine Science and Technology, 2005

A new method for designing propeller blade sections is presented. A vortex lattice method is used to evaluate the performance and the time-dependent pressure distribution on the blade surface in a non-uniform flow, while efficient optimization algorithms are used to modify the blade sections. Two different designs were carried out in this study. The first was a design to realize a target pressure distribution in a rotating three-dimensional flow. A two-dimensional wing theory was used to obtain the target pressure distribution. The predicted increase in efficiency and the reduction in the cavity volume were confirmed by model experiments. The second was a design to maximize the propeller efficiency. By this method, the propeller efficiency was improved by 1.2% under the constrains of constant thrust and a prescribed margin for face cavitation.

High-Fidelity Swept and Leaned Rotor Blade Design Optimization Using Evolutionary Algorithm

16th AIAA Computational Fluid Dynamics Conference, 2003

In this paper, aerodynamic blade design optimization for a transonic axial compressor has demonstrated by using an evolutionary-algorithm-based high-fidelity design optimization tool. The present method uses a three-dimensional Navier-Stokes solver named TRAF3D for aerodynamic analysis to represent flow fields accurately and the realcoded ARGA for efficient and robust design optimization. The present method successfully obtained a design that reduced entropy production by more than 16% compared with the rotor67 while satisfying constraints on the mass flow rate and the pressure ratio. This study gave some insights into design optimization of a swept and leaned rotor blade for transonic axial compressors.

Helicopter Main Rotor Blade Parametric Design for a Preliminary Aerodynamic Analysis Supported by CFD or Panel Method

Materials

This work is the preliminary part of a research program which is aimed at finding some new methods and design solutions for helicopter main rotor multidisciplinary optimization. The task was to develop a parametric geometric model of a single-blade main rotor applicable for varied methods of numerical aerodynamic modeling. The general analytical assumptions for the parametric main rotor design were described. The description of the main rotor blade parametric design method based on Open GRIP graphical programming was presented. Then, the parametric model of a blade was used for aerodynamic models independently developed for panel method and advanced CFD solver. The results obtained from the CFD simulations and panel analysis for main rotor aerodynamics were compared and assessed using analytical calculations. The calculations and simulations for a single-blade and completed rotor were performed for different helicopter weights and rotor pitch angles. The results of different compute...

Parametrization of the main rotor and working environment for different flight conditions – Computational Fluid Dynamics analysis as an application for multidisciplinary optimization

Journal of Theoretical and Applied Mechanics, 2023

The paper shows a method of aerodynamic modelling of the whole rotor and exemplary results obtained from complex analyses. The analytical basis of rotor aerodynamics for different phases of the helicopter flight is shown. The analytical calculations are provided to model a single blade motion according to its azimuth angle and to validate the obtained results. The parametric design method is shown to be applied for different blade planform shapes and various section airfoils. The Computational Fluid Dynamics (CFD) fluid domain for the flow around the blade is also prepared using a parametric method. The parametric graphic script is developed to create the flow domain for a one-blade simulation or for a complete n-bladed rotor effect. The obtained blade model with enclosure is implemented into CFD environment. The method for fluid mesh preparation and the way of defining its properties are given. The simulation is carried out as transient for the n-bladed rotor. In this simulation, various flight conditions are taken into account. Real rotary motion of the blades is simulated with artificially enforced mesh motion. The obtained numerical results are compared then with analytical assumptions. The simulation findings which are the inputs for further analysis are shown with graphical representations. As an output of the research, new options for main rotor optimization are developed. The usage of combined parametric modelling confirmed with aerodynamic analysis for different flight conditions is shown in the work as a new perspective for design optimization of the main rotor.

Wind Turbine Blade Design with Computational Fluid Dynamics Analysis

2017

Although there are many blade profile have been improved for use in aviation and energy sector, there is still needed blade profiles which have higher performance especially the commercial horizontal axis wind turbine efficiency is taken into account. The purpose of this study is to obtain the new blade profiles which have higher lift (CL) and drag (CD) coefficients for wind turbine making geometric modifications on several NACA wing profile systematically. For this purpose, the performance of NACA and developed new profiles have been compared with each other using computational fluid dynamics analysis and it is seen that the new developed profiles have higher performance than NACA profiles. Later on, according to the Blade Element Momentum Theory (BEM Theory) turbine blades are designed with developed new profiles and 3-dimensional CFD analyses are performed. Increase in torque in the wind turbine is determined.