Wind Turbine Adaptive Blade Integrated Design and Analysis

This project aims to develop efficient and robust tools for optimal design of wind turbine adaptive blades. In general, wind turbine adaptive blade design is an aero-structure coupled design process, in which, the evaluation of aerodynamic performance cannot be carried out precisely without structural deformation analysis of the adaptive blade. However, employing finite element analysis (FEA) based structural analysis commercial packages as part of the aerodynamic objective evaluation process has been proven time consuming and it results in inefficient and redundant design optimisation of adaptive blades caused by elastic-coupled (bend-twist or stretch-twist) iteration. In order to achieve the goal of wind turbine adaptive blade integrated design and analysis, this project is carried out from three aspects. Firstly, a general geometrically linear model for thin-walled composite beams with multi-cell, non-uniform cross-section and arbitrary lay-ups under various types of loadings is developed for implementing structural deformation analysis. After that, this model is validated by a simple box-beam, single- and multi-cell wind turbine blades. Through validation, it denotes that this thin-walled composite beam model is efficient and accurate for predicting the structural deformations compared to FEA based commercial packages (ANSYS). This developed beam model thus provides more probabilities for further investigations of dynamic performance of adaptive blades. Secondly in order to investigate the effects of aero elastic tailoring and implanting elastic coupling on aerodynamic performance of adaptive blades, auxiliary software tools with graphical interfaces are developed via MATLAB codes. Structural/material characteristics and configurations of adaptive blades (i.e. elastic coupling topology, layup configuration and material properties of blade) are defined by these auxiliary software tools. By interfacing these software tools to the structural analysers based on the developed thin-walled composite beam model to an aerodynamic performance evaluator, an integrated design environment is developed. Lastly, by using the developed thin-walled composite beam model as a search platform, the application of the decoupled design method, a method of design of smart aero-structures based on the concept of variable state design parameter, is also extended

State of the Art in the Optimisation of Wind Turbine Performance Using CFD

Wind energy has received increasing attention in recent years due to its sustainability and geographically wide availability. The efficiency of wind energy utilisation highly depends on the performance of wind turbines, which convert the kinetic energy in wind into electrical energy. In order to optimise wind turbine performance and reduce the cost of next-generation wind turbines, it is crucial to have a view of the state of the art in the key aspects on the performance optimisation of wind turbines using Computational Fluid Dynamics (CFD), which has attracted enormous interest in the development of next-generation wind turbines in recent years. This paper presents a comprehensive review of the state-of-the-art progress on optimisation of wind turbine performance using CFD, reviewing the objective functions to judge the performance of wind turbine, CFD approaches applied in the simulation of wind turbines and optimisation algorithms for wind turbine performance. This paper has been written for both researchers new to this research area by summarising underlying theory whilst presenting a comprehensive review on the up-to-date studies, and experts in the field of study by collecting a comprehensive list of related references where the details of computational methods that have been employed lately can be obtained

Simulating the aerodynamic performance and wake dynamics of a vertical-axis wind turbine

The accurate prediction of the aerodynamics and performance of vertical-axis wind turbines is essential if their design is to be improved but poses a signifi cant challenge to numerical simulation tools. The cyclic motion of the blades induces large variations in the angle of attack of the blades that can manifest as dynamic stall. In addition, predicting the interaction between the blades and the wake developed by the rotor requires a high-fi delity representation of the vortical structures within the fl ow fi eld in which the turbine operates. The aerodynamic performance and wake dynamics of a Darrieus-type vertical-axis wind turbine consisting of two straight blades is simulated using Brown’s Vorticity Transport Model. The predicted variation with azimuth of the normal and tangential force on the turbine blades compares well with experimental measurements. The interaction between the blades and the vortices that are shed and trailed in previous revolutions of the turbine is shown to have a signifi cant effect on the distribution of aerodynamic loading on the blades. Furthermore, it is suggested that the disagreement between experimental and numerical data that has been presented in previous studies arises because the blade–vortex interactions on the rotor were not modelled with sufficient fidelity

Kesediaan pelajar dari aspek kemahiran teknikal terhadap pembentukan kebolehkerjaan di Kolej Vokasional Wilayah Selatan

Graduan yang menganggur terus menjadi masalah yang semakin meruncing di Malaysia. Terdapat majikan yang menganggap kompetensi akademik sahaja tidak mencukupi dan mula meminta institusi pendidikan tinggi untuk menghasilkan graduan yang dilengkapi dengan kemahiran teknikal. Kajian ini merupakan satu kajian untuk mengenalpasti kesediaan pelajar dari aspek kemahiran teknikal terhadap pembentukan kebolehkerjaan di kolej vokasional wilayah selatan. Seramai 113 responden telah dipilih sebagai sampel kajian. Instrumen kajian yang digunakan dalam kajian ini ialah borang soal selidik yang mengandungi 60 item. Kajian rintis dijalankan untuk mendapatkan nilai alpha bagi instrument kajian di mana nilai alpha bagi aspek kemahiran teknikal adalah α = 0.962 dan bagi aspek kebolehkerjaan adalah α = 0.954 . Data yang diperoleh dianalisis dengan menggunakan Statistical Package for Social Science Version 20 (SPSS 20). Analisis deskriptif dalam bentuk skor min digunakan untuk melihat kesediaan pelajar. Hasil kajian mendapati bahawa tahap kesediaan pelajar dari aspek kemahiran teknikal terhadap pembentukan kebolehkerjaan di Kolej Vokasional Kluang, Kolej Vokasional Batu Pahat dan Kolej Vokasional Muar berada pada tahap tinggi. Hasil kajian juga menunjukkan terdapat perbezaan antara jantina pelajar dari aspek kemahiran teknikal yang mempengaruhi kesediaan pelajar terhadap pembentukan kebolehkerjaa

Study of Turbofan Engines Designed for Low Enery Consumption

Subsonic transport turbofan engine design and technology features which have promise of improving aircraft energy consumption are described. Task I addressed the selection and evaluation of features for the CF6 family of engines in current aircraft, and growth models of these aircraft. Task II involved cycle studies and the evaluation of technology features for advanced technology turbofans, consistent with initial service in 1985. Task III pursued the refined analysis of a specific design of an advanced technology turbofan engine selected as the result of Task II studies. In all of the above, the impact upon aircraft economics, as well as energy consumption, was evaluated. Task IV summarized recommendations for technology developments which would be necessary to achieve the improvements in energy consumption identified

Energy efficient engine high-pressure turbine detailed design report

The energy efficient engine high-pressure turbine is a single stage system based on technology advancements in the areas of aerodynamics, structures and materials to achieve high performance, low operating economics and durability commensurate with commercial service requirements. Low loss performance features combined with a low through-flow velocity approach results in a predicted efficiency of 88.8 for a flight propulsion system. Turbine airfoil durability goals are achieved through the use of advanced high-strength and high-temperature capability single crystal materials and effective cooling management. Overall, this design reflects a considerable extension in turbine technology that is applicable to future, energy efficient gas-turbine engines

Energy efficient engine: Turbine intermediate case and low-pressure turbine component test hardware detailed design report

A four stage, low pressure turbine component has been designed to power the fan and low pressure compressor system in the Energy Efficient Engine. Designs for a turbine intermediate case and an exit guide vane assembly also have been established. The components incorporate numerous technology features to enhance efficiency, durability, and performance retention. These designs reflect a positive step towards improving engine fuel efficiency on a component level. The aerodynamic and thermal/mechanical designs of the intermediate case and low pressure turbine components are presented and described. An overview of the predicted performance of the various component designs is given

Vertical axis wind turbine performance prediction: a new approach to the double multiple streamtube model

The vertical axis wind turbines (VAWT) have been suffering an increased acceptance for urban wind turbines integration in the future smart grid for decentralized generation (DG). The VAWT have several advantages over the more conventional horizontal axis wind turbines (HAWT): the smaller number of components; low sound emissions; their insensitivity to fast changes in wind flow direction; a lower architectural visual impact; the ability to operate closer to the ground; and others. But, the VAWT aerodynamic performance is more complex to simulate and predict due to its three dimensional operation. Several mathematical models have been presented to predict the VAWT performance, such as the double multiple streamtube (DMS) model. With the aim of presenting a tool to ease the study of complex shaped VAWTs, being at the same time able to be easily integrated in computational design tools, a new approach to the DMS model is presented in this paper

Modeling and control of a variable speed variable pitch angle prototype wind turbine

This paper focuses on modeling, control and simulation of a 500 KW horizontal axis prototype wind turbine that is being developed in the context of the MILRES (National Wind Energy Systems) Project in Turkey. The prototype turbine is designed as variable speed variable pitch angle wind turbine due to its advantages in efficiency and the structure. Aerodynamic, mechanical and electrical subsystems along with pitch and torque controllers are designed in both Matlab/Simulink and S4WT simulation environments. The main control purpose is to generate a power curve that is close to the ideal power curve where the energy efficiency is maximized below the nominal wind speed of 11 m/s and the power is limited to the nominal value above the nominal wind speed. Turbsim is integrated with both environments to generate a realistic wind profile of Kaimal turbulence model. The performance analysis of the prototype turbine is done under the power production scenario in both environments. Start up, emergency stop, shut down and parked scenarios are also implemented in S4WT