scholarly journals Simulating NACA Equations Used in Optimizing Wind Turbine Blade Design: محاكاة معادلات NACA واستخدامها لتحسين تصميم شفرة العنفة الريحية

2021 ◽  
Vol 5 (4) ◽  
pp. 164-152
Author(s):  
Suzanne Ahmad Radwan Masri, Kheir Eddine Tarsha Kurdi, Ahmad Suzanne Ahmad Radwan Masri, Kheir Eddine Tarsha Kurdi, Ahmad
Keyword(s):  
High Efficiency ◽  
Operating Performance ◽  
Line Length ◽  
Blade Design ◽  
Blade Surface ◽  
Blade Profile ◽  
Optimal Operating ◽  
Turbine Blade Design ◽  
Twisting Angle ◽  
Great Energy

Aerodynamic scientists are interested in geometry definition and possible geometric shapes that would be useful in design. This paper illustrates a simulation of a NACA four digits airfoil blade profile using MATLAB. As airfoil design became more sophisticated, this basic approach has been modified to include additional variables, and suggestions for the chord line length at the root and at the end of the blade. as well as changes in the twisting angle of the blade and its thickness, this helps to reduce the weight of the blade significantly Simulating NACA equations is very useful in obtaining coordinates of airfoil curvature for the whole series of NACA four digits, which is very effective in optimizing blade design. In order to get an optimal operating performance and high efficiency for the airfoil, the blade surface must be smooth and does not suffer any discontinuities or undefined cases, which cause separation of the boundary layer during the airflow, and get as a result great energy losses. Therefore, the conditions for the continuity of the blade was extracted using mathematical analysis, so the air flow does not suffer any interruptions which reduce the efficiency. This enable us to determine the locations of the maximum thickness of the blade sections on the chord along the blade, in addition to specifying conditions for the chord line length at the root and at the end of the blade which keep the blade curvature continuous and doesn’t have any irregular points, which also facilities writing the necessary programs.

Design of a Single Stage Variable Pitch Axial Fan

2017 ◽  
Author(s):  
Tommaso Bonanni ◽  
Alessandro Corsini ◽  
Giovanni Delibra ◽  
David Volponi ◽  
Anthony G. Sheard ◽  
...  
Keyword(s):  
High Efficiency ◽  
Fluid Dynamic ◽  
Single Stage ◽  
Department Of Energy ◽  
Development Effort ◽  
Blade Design ◽  
The European Union ◽  
Blade Profile ◽  
Axial Fan ◽  
Work Distribution

The European Union imposed minimum industrial fan efficiency levels in 2013 and then increased them in 2015. In the USA, the Department of Energy (DoE) is also developing regulations aimed at eliminating inefficient industrial fans from the market by 2023. A consequence of this regulatory activity is a need to apply design methods originally developed within the aerospace community to the design of high efficiency industrial fans. In this paper, we present a process used to design, numerically verify and experimentally test a high-pressure single-stage axial fan. The goal was a fan design capable of working over a range of blade angles in combination with a single fixed cambered plate stator. We present the process used when selecting blade airfoil sections and the vortex distribution along the blade span. The selected methodology is based on a coupling between the aerodynamic response of each blade profile and the chosen vortex distribution, creating a direct link between the load distribution and the aerodynamic capability of the blade profile section. This link is used to develop radial distributions of blade twist and chord for the selected blade profiles that result in the required radial work distribution. The design method has been enhanced through intermediate verifications using two different numerical methodologies. The methodologies are based on different approaches, in so doing providing confidence in the verification process. The final blade design has been analyzed using a three-dimensional computational fluid dynamic (CFD) code. Results of the CFD analysis indicate that performance of the final blade design is consistent with the design specifications. The paper concludes with a comparison between predicted and experimentally measured performance. The need is clarified for balance between computational and empirical approaches. When used together the development effort results in a lower cost and higher efficiency design than would have been possible using either approach in isolation.

Advances in ocean current turbine blade design

2021 ◽  
Author(s):  
Hassan Mahfuz ◽  
Nicholas Asseff ◽  
Mohammad Wasim Akram ◽  
Fang Zhou ◽  
Takuya Suzuki ◽  
...  
Keyword(s):  
Turbine Blade ◽  
Ocean Current ◽  
Blade Design ◽  
Turbine Blade Design ◽  
Current Turbine

scholarly journals Low-pressure reversible axial fan with straight profile blades and relatively high efficiency

2012 ◽  
Vol 16 (suppl. 2) ◽  
pp. 593-603 ◽  
Author(s):  
Zivan Spasic ◽  
Sasa Milanovic ◽  
Vanja Sustersic ◽  
Boban Nikolic
Keyword(s):  
Numerical Simulations ◽  
High Efficiency ◽  
Suction Side ◽  
Standard Test ◽  
Maximum Efficiency ◽  
Specific Work ◽  
Blade Profile ◽  
Operating Characteristics ◽  
Axial Fan ◽  
Increase Energy Efficiency

The paper presents the design and operating characteristics of a model of reversible axial fan with only one impeller, whose reversibility is achieved by changing the direction of rotation. The fan is designed for the purpose of providing alternating air circulation in wood dryers in order to reduce the consumption of electricity for the fan and increase energy efficiency of the entire dryer. To satisfy the reversibility of flow, the shape of the blade profile is symmetrical along the longitudinal and transversal axes of the profile. The fan is designed with equal specific work of all elementary stages, using the method of lift forces. The impeller blades have straight mean line profiles. The shape of the blade profile was adopted after the numerical simulations were carried out and high efficiency was achieved. Based on the calculation and conducted numerical simulations, a physical model of the fan was created and tested on a standard test rig, with air loading at the suction side of the fan. The operating characteristics are shown for different blade angles. The obtained maximum efficiency was around 0.65, which represents a rather high value for axial fans with straight profile blades.

scholarly journals Wind Turbine Blade Design Review

2012 ◽  
Vol 36 (4) ◽  
pp. 365-388 ◽  
Author(s):  
P.J. Schubel ◽  
R.J. Crossley
Keyword(s):  
Wind Turbine ◽  
Turbine Blade ◽  
Wind Turbine Blade ◽  
Blade Design ◽  
Design Review ◽  
Turbine Blade Design

scholarly journals A Unified Variable-Domain Variational Approach to Hybrid Problems of Compressible Blade-to-Blade Flow

1991 ◽  
Author(s):  
Gao-Lian Liu ◽  
Shan Yan
Keyword(s):  
Systematic Approach ◽  
Variable Domain ◽  
Natural Boundary Condition ◽  
Unified Theory ◽  
Blade Design ◽  
Blade Surface ◽  
The Finite Element Method ◽  
Natural Boundary ◽  
Functional Variation ◽  
Numerical Tests

A unified theory of various hybrid problems for blade-to-blade compressible flow is developed herein via the functional variation with variable domain. Two variational principle (VP) families for three typical hybrid problems are derived, following a systematic approach (Liu, 1990a). Full advantage is taken of the natural boundary condition and suction/blowing along the blade surface are accommodated. This theory is aimed at offering a new theoretical basis for the finite element method (FEM) and various ways for blade design and/or modification, and it also constitutes an important part of optimal cascade theory (Liu,1987b). Based on these VPs, a new FEM with self-adjusting nodes is also suggested, and the numerical tests yield good results.

Influence of Turbocharger Turbine Blade Geometry on Vibratory Blade Stresses

2018 ◽  
Vol 141 (2) ◽  
Author(s):  
Pavan Naik ◽  
Bernhard Lehmayr ◽  
Stefan Homeier ◽  
Michael Klaus ◽  
Damian M. Vogt
Keyword(s):  
Turbine Blade ◽  
High Cycle Fatigue ◽  
Pressure Field ◽  
Spanwise Direction ◽  
Blade Design ◽  
Centrifugal Forces ◽  
Baseline Design ◽  
Combined Stresses ◽  
Blade Thickness ◽  
Turbine Blade Design

In this paper, a method to influence the vibratory blade stresses of mixed flow turbocharger turbine blade by varying the local blade thickness in spanwise direction is presented. Such variations have an influence on both the static and the vibratory stresses and therefore can be used for optimizing components with respect to high-cycle fatigue (HCF) tolerance. Two typical cyclic loadings that are of concern to turbocharger manufacturers have been taken into account. These loadings arise from the centrifugal forces and from blade vibrations. The objective of optimization in this study is to minimize combined effects of centrifugal and vibratory stresses on turbine blade HCF and moment of inertia. Here, the conventional turbine blade design with trapezoidal thickness profile is taken as baseline design. The thicknesses are varied at four spanwise equally spaced planes and three streamwise planes to observe their effects on static and vibratory stresses. The summation of both the stresses is referred to as combined stress. In order to ensure comparability among the studied design variants, a generic and constant excitation order-dependent pressure field is used at a specific location on blade. The results show that the locations of static and vibratory stresses, and hence the magnitude of the combined stresses, can be influenced by varying the blade thicknesses while maintaining the same eigenfrequencies. By shifting the maximum vibratory stresses farther away from the maximum static stresses, the combined stresses can be reduced considerably, which leads to improved HCF tolerance.

Blade Loading and Numerical Slip Factor of Centrifugal Compressor Impellers

1999 ◽  
Author(s):  
JongSik Oh
Keyword(s):  
State Of The Art ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Blade Design ◽  
Direct Relation ◽  
Blade Profile ◽  
Blade Loading ◽  
Slip Factor ◽  
Compressible Turbulent Flow ◽  
Good Agreement

Abstract Through the state-of-the-art CFD approach, the Eckardt radial bladed and backswept impellers were analyzed to investigate the effect of blade loadings from blade design shape on the slip factor variation for the change of the flow rate. In addition, a new design of the blade profile was arbitrarily attempted to generate a center-loading pattern in the Eckardt backswept impeller. Three dimensional compressible turbulent flow analysis was applied, with the Baldwin-Lomax turbulence model adopted, to get the numerical slip factor, using the mass-averaged concept, at the discharge plane of each impeller. The numerical slip factors are in good agreement with the experimental ones, and the Wiesner’s slip factors are found to deviate further from the numerical and experimental ones, especially in the two backswept impellers. The deviation angles and the blade loadings in the meridional channel are found in no direct relation with the trend of change of the slip factors. Blade-to-blade loadings in midspan location are, however, found in direct relation, especially at the sections where maximum loadings are to be expected. That information can be utilized in establishing an improved expression for slip factor in the future.

Sign in / Sign up

Export Citation Format

Share Document