Author: Xin Wang Publisher: LAP Lambert Academic Publishing ISBN: 9783847300328 Category : Languages : en Pages : 192
Book Description
The total worldwide base of installed wind energy peak capacity reached 197 GW by the end of 2010. Wind turbine systems are being installed often in mountains and cold weather regions, due to their high wind energy potential. Harsh cold weather climates affect wind turbine performance. Ice accretion and irregular shedding during turbine operation lead to load imbalances, vibration and structural failures, often causing the turbine to shut off. This book presents an experimental investigation including three important fundamental aspects: energy losses of wind energy while a wind turbine is operating under icing conditions; aerodynamic characteristics of an airfoil during a simulated icing event and heat transfer characteristics of the airfoil with and without liquid water content at varying angles of attack. The drag, lift and moment are measured by a force balance system to obtain the aerodynamics of an iced airfoil. The book also quantifies the power loss under various icing conditions. The data obtained can be used to validate numerical models and predict heat transfer characteristics when wind turbines operate in cold climate regions.
Author: R.S. Amano Publisher: WIT Press ISBN: 1784660043 Category : Science Languages : en Pages : 197
Book Description
Focusing on Aerodynamics of Wind Turbines with topics ranging from Fundamental to Application of horizontal axis wind turbines, this book presents advanced topics including: Basic Theory for Wind turbine Blade Aerodynamics, Dynamics-Based Health Monitoring and Control of Wind Turbine Rotors, Experimental Testing of Wind Turbines Using Wind Tunnels with an Emphasis on Small-Scale Wind Turbines Under Low-Reynolds Numbers, Computational Methods, Ice Accretion for Wind Turbines and Influence of Some Parameters, and Special Structural Reinforcement Technique for Wind Turbine Blades. Consequently, for these reasons, analysis of wind turbines will attract readers not only from the wind energy community but also in the gas turbines heat transfer and fluid mechanics community.
Author: Yan Li Publisher: BoD – Books on Demand ISBN: 1837690146 Category : Technology & Engineering Languages : en Pages : 120
Book Description
This book includes six chapters on wind turbine icing. For wind turbines operating in cold regions, icing often occurs on blade surfaces in winter. This ice accretion can change the aerodynamic shape of the blade airfoil, causing performance degradation and loss of power generation, even leading to operational accidents. This book focuses on the recent research progress on wind turbine icing. Chapters address such topics as the effect of icing conditions on the icing distribution characteristics of a blade airfoil for vertical-axis wind turbines, power loss estimation in wind turbines due to icing, wind turbine icing prediction methods, especially those using machine learning, the icing process of a single water droplet on a cold aluminum plate surface, the main theories of the icing adhesive mechanism, and theoretical and experimental studies on the ultrasonic de-icing method for wind turbine blades. This book is a valuable reference for researchers and engineers engaged in wind turbine icing and anti-icing research.
Author: Hui Hu Publisher: Academic Press ISBN: 0323903258 Category : Technology & Engineering Languages : en Pages : 224
Book Description
Wind Turbine Icing Physics and Anti-/De-Icing Technology gives a comprehensive update of research on the underlying physics pertinent to wind turbine icing and the development of various effective and robust anti-/de-icing technology for wind turbine icing mitigation. The book introduces the most recent research results derived from both laboratory studies and field experiments. Specifically, the research results based on field measurement campaigns to quantify the characteristics of the ice structures accreted over the blades surfaces of utility-scale wind turbines by using a Supervisory Control and Data Acquisition (SCADA) system and an Unmanned-Aerial-Vehicle (UAV) equipped with a high-resolution digital camera are also introduced. In addition, comprehensive lab experimental studies are explored, along with a suite of advanced flow diagnostic techniques, a detailed overview of the improvements, and the advantages and disadvantages of state-of-the-art ice mitigation strategies. This new addition to the Wind Energy Engineering series will be useful to all researchers and industry professionals who address icing issues through testing, research and industrial innovation. - Covers detailed improvements and the advantages/disadvantages of state-of-the-art ice mitigation strategies - Includes condition monitoring contents for lab-scale experiments and field tests - Presents the potential of various bio-inspired icephobic coatings of wind turbine blades
Author: Lorenzo Battisti Publisher: Springer ISBN: 3319051911 Category : Technology & Engineering Languages : en Pages : 355
Book Description
This book addresses the key concerns regarding the operation of wind turbines in cold climates and focuses in particular on the analysis of icing and methods for its mitigation. Topics covered include the implications of cold climates for wind turbine design and operation, the relevance of icing for wind turbines, the icing process itself, ice prevention systems and thermal anti-icing system design. In each chapter, care is taken to build systematically on the basic knowledge, providing the reader with the level of detail required for a thorough understanding. An important feature is the inclusion of several original analytical and numerical models for ready computation of icing impacts and design assessment. The breadth of the coverage and the in-depth scientific analysis, with calculations and worked examples relating to both fluid dynamics and thermodynamics, ensure that the book will serve not only as a textbook but also as a practical manual for general design tasks.
Author: David Getz Publisher: ISBN: Category : Languages : en Pages :
Book Description
There has been a substantial growth in the total installed wind energy capacity worldwide, especially in China and the United States. Icing difficulties have been encountered depending on the location of the wind farms. Wind turbines are adapting rotor ice protection approaches used in rotorcraft applications to reduce aerodynamic performance degradation related to ice formation. Electro-thermal heating is one of the main technologies used to protect rotors from ice accretion and it is one of the main technologies being considered to protect wind turbines. In this research, an anti-icing configuration using electro-thermal heating was explored to find optimum power density requirements to keep the rotor blade free of ice at all times. The objective of these experiments were to identify the feasibility of the power requirements from the stake holders and determine an initial power density for the de-icing approach. The electro-thermal heater system located on the spinning wind turbine representative blade sections were powered through a slip-ring. The wind turbine sections were scale models of the 80% span region of a generic 1.5 MW wind turbine blade. The icing cloud impact velocity was matched with a 1.5 MW wind turbine at full production. Three icing conditions were selected for this research: Light, Medium and Severe. Light icing conditions were created using clouds at -8C with a 0.2 g/m3 liquid water content (LWC) and water droplets of 20 m median volumetric diameter (MVD). Medium icing condition clouds had a LWC of 0.4 g/m3 and 20 m MVD, also at -8C. Severe icing conditions had an LWC of 0.9 g/m3 and 35 m MVD at -8C. Experimental anti-icing results were compared with LEWICE, a NASA developed analytical heat transfer software. The average output temperature discrepancy between the suction and pressure sides of the airfoil were 39.5% and 11.1%, respectively. The correlation coefficient of the pressure-side output temperature and power density showed a positive correlation of 0.9516. The anti-icing configuration with the allocated power requirements was deemed unfeasible. This thesis then discusses the design process required to develop a de-icing ice protection system (ice is allowed to accrete to then be removed) for wind turbines and a design procedure was developed. Initially, ice accretion thickness gradients along the span of the rotor blade for light, medium and severe icing conditions were collected. Ice accretion rates along the span of the representative full-scale turbine blade in the severe icing condition ranged from 1.125 mm/min to 1.85 mm/min. Given the maximum power available for the de-icing system (100 kW), heating zones were determined along the span and the chord of the blade. The maximum available power density for each span-wise heater section was 0.385 W/cm2. The heating sequence started at the tip of the blade, to allow de-bonded ice to shed off along the span of the rotor blade due to centrifugal forces. Given the continuity of the accreted ice, heating a zone could de-bond the ice over that specific zone, but the ice formation could not detach from the blade as it would be cohesively connected to the ice over its adjacent inboard zone. The research determined the critical minimum ice thickness required to shed the accreted ice mass with a given amount of power availability by not only melting the ice interface over the zone, but also creating sufficient tensile forces to break the cohesive ice forces between two adjacent heating zones. The quantified minimum ice thickness to overcome ice cohesive forces were obtained for all identified icing conditions. The minimum ice thicknesses required for effective shedding at 26.7%, 44.4% and 62.2% of the span were 7.2mm, 5mm and 4mm, respectively. The digitized ice areas of these thicknesses were used to calculate the centrifugal force at each heater section. The experiment data was critical in the design of a time sequence controller that allows consecutive de-icing of heating zones along the span of the wind turbine blade with the allocated power.
Author: Ernst Rudolf Georg Eckert Publisher: ISBN: Category : Aerodynamics Languages : en Pages : 44
Book Description
Summary: Transpiration and film cooling promise to be effective methods of cooling gas-turbine blades; consequently, analytical and experimental investigations are being conducted to obtain a better understanding of these processes. This report serves as an introduction to these cooling methods, explains the physical processes, and surveys the information available for predicting blade temperatures and heat-transfer rates. In addition, the difficulties encountered in obtaining a uniform blade temperature are discussed, and the possibilities of correcting these difficulties are indicated. Air is the only coolant considered in the application of these cooling methods.
Author: Charles F. Zalabak Publisher: ISBN: Category : Aircraft gas-turbines Languages : en Pages : 32
Book Description
A water-cooled turbine was fabricated and tested to determine the effect of a connecting passage at the turbine rotor blade tip between a radial coolant passage 0.10 inch in diameter (length-diameter ratio = 25.5) and radial coolant passages in the legnth-diameter range of 5.1 to 20.4. Coolant flow through the connecting passage is induced by free-convection forces in the radial passages.
Author: Xin Wang
Author: 
Author: Xin Wang
Author: R.S. Amano
Author: Yan Li
Author: Hui Hu
Author: Lorenzo Battisti
Author: David Getz
Author: Ernst Rudolf Georg Eckert
Author: Charles F. Zalabak