Browse Topic: Wind power

Items (94)

2022-28-044611/09/2022

The ability to precisely control electrical voltages on a large scale has made possible many efficient, powerful innovations, from high-speed electric trains to wind turbines to electric drive motors for everything from heavy earthmoving equipment to personal electric vehicles (EVs). But the equipment that manages this process — including power inverters, thyristors and variable-speed drives — requires high-performance power electronics cooling. As temperatures rise, the efficiency, reliability, and life spans of these devices drop, and the power electronics inside HEVs and EVs are no exception. Advancements in power electronic thermal management technologies will enable next generation automotive to fulfill increasingly demanding mission objectives. DC-DC converter and inverter systems slated for higher performances, reliable and sustainable applications. Even with very high efficiencies, the components of these systems produce kilowatts of power loss in the form of heat. The current

Sahoo, Pranati

The mechanism of spur gear tooth profile deformation due to interference-fit assembly and the resultant effects on transmission error, bending stress, and tip diameter and its sensitivity to gear geometry.

2022-01-075003/29/2022

Gear profile deviation is the difference in gear tooth profile from the ideal involute geometry. There are many causes that result in the deviation. Deflection under load, manufacturing, and thermal effects are some of the well-known causes that have been reported to cause deviation of the gear tooth profile. The profile deviation caused by gear tooth profile deformation due to interference-fit assembly has not been discussed previously. Engine timing gear trains, transmission gearboxes, and wind turbine gearboxes are known to use interference-fit to attach the gear to the rotating shaft. This paper discusses the interference-fit joint design and the mechanism of tooth profile deformation due to the interference-fit assembly in gear trains. A new analytical method to calculate the profile slope deviation change due to interference-assembly of parallel axis spur gears is presented. The effectiveness of the proposed computational algorithm to predict the deformation is demonstrated by

Joshi, Yashodhan, Chowdhury, Sanjib

Study on the Influence of Mass Flow Rate over a National Advisory Committee for Aeronautics 6321 Airfoil Using Improved Blowing and Suction System for Effective Boundary Layer Control

01-14-02-0011

08/06/2021

The numerical analysis of the three-dimensional (3D) flow over a National Advisory Committee for Aeronautics (NACA) 6321 airfoil to evaluate the mass flow rate by using a novel method Improved Blowing and Suction System (IBSS) to control the boundary layer is presented in this study. Analysis is performed based on 3D Reynolds-Averaged Navier-Stokes (RANS) equation with a K-omega SST solver. The aerodynamic performance of the NACA 6321 is analyzed at a Mach number of 0.10 with three different mass flow rates, namely, 0.08 kg/s, 0.10 kg/s, and 0.12 kg/s. From the study, it is seen that when the mass flow rate decreased, the aerodynamics performance also reduced, and the aerodynamic performance improved with the increase in mass flow rate. Results also show that a mass flow rate of 0.10 kg/s improved the stalling angle of attack (AoA) by 60% and coefficient of lift (CL) by 50%, enabling optimum efficiency of the aircraft wing in all aspects compared to the baseline airfoil model. The mass

Karuppiah, Balaji, Wessley, Jims John

High-Efficiency Megawatt Motor

TBMG-3813712/01/2020

Innovators at NASA Glenn Research Center have designed a High-Efficiency Megawatt Motor (HEMM), a wound-field partially superconducting machine. The HEMM implements a combination of superconducting and non-superconducting elements, along with an integrated cryocooler, to achieve some of the benefits of a superconducting motor without the need for an external cryogenic system.

Self-Powered Alarm Fights Forest Fires, Monitors Environment

TBMG-3766409/01/2020

In a new study, a team of Michigan State University scientists designed and fabricated a remote forest fire detection and alarm system powered by nothing but the movement of the trees in the wind. The device, known as MC-TENG — short for multilayered cylindrical triboelectric nanogenerator — generates electrical power by harvesting energy from the sporadic movement of the tree branches from which it hangs.

Fluid-Filled Frequency-Tunable Mass Damper

TBMG-3739308/01/2020

NASA Marshall innovators have developed the Fluid-Filled Frequency-Tunable Mass Damper (FTMD) that allows for significant distribution of loads while also providing a simple mechanism that allows for the capability to change its frequency of mitigation with negligible impact on the damper system.

Shape Sensing Innovations Dramatically Improve Structural Design Tools

TBMG-3579301/01/2020

Advances in fiber optic shape sensing developed at NASA's Armstrong Flight Research Center are enabling the development of next-generation flexible aircraft wings that maximize structural efficiency and reduce weight, improving fuel efficiency. These same advances will help engineers design stronger bridges, buildings, ocean vessels, and more.

Wind Event Warning System

TBMG-3545411/01/2019

NASA Langley Research Center developed a wind event warning technology that provides a practical early warning system (5-10 minutes) for a severe change in the wind vector. Events such as gusts, shear, microbursts, or thunderstorm outflows can be detected in time to prevent damage to wind turbines or help airports prevent damage to aircraft. Further, an alternative power source could be ramped up or down as needed to accommodate the power draw in the electrical grid.

Demand Side Load Management by Using Priority Based Load Shedding Algorithm with and without Renewable Energy Generation

2019-28-007310/11/2019

Demand side load management (DSLM) emphasizes control of the power demanded, by reducing the peak load and control of energy utilization of the system. DSLM is introduced to improve the flexibility of the grid power usage and also to aid the utilization of Renewable Energy Generation (REG) which is intermittent. In this work, implementation of load shedding (LS) algorithm for the residential load is performed with the limit of power as constraint, considering REG and grid in three different modes of operation. Solar and Wind power are the REG considered in this work. Priority Based Load Shedding (PBLS) is performed to limit the power consumption of equipment during peak hours with the implementation of varying pricing signal. In order to implement PBLS, three residential user load data for 24 hours is considered. The users are categorized as low, medium and high priority user. The priority of the user is based on the load consumption for 24 hours. The proposed LS scheme is performed

Rathinam, Rajarajeswari, Dayalan, Suchitra

Structure Deformation Calculation Program for Structural Shape Monitoring

TBMG-3528910/01/2019

Researchers at NASA’s Armstrong Flight Research Center are pioneering shape-sensing technologies that seek to maximize structural integrity and efficiency. A new and versatile computer program offers critical shape-monitoring capabilities and has applications for a wide variety of structures.

Schlieren System Captures Brilliant Shockwave Images

TBMG-3525410/01/2019

Supersonic flight over land is generally prohibited because sonic booms created by shockwaves disturb people on the ground and can damage property. Armstrong innovators are working to solve this problem with a novel system for capturing images of shockwaves created by supersonic aircraft. The Background Oriented Schlieren Using Celestial Objects (BOSCO) technology uses a celestial object, such as the Sun, as a background to secure unique, measurable shockwave images of full-scale aircraft. The patented image-processing technology captures hundreds of observations with each shockwave, benefitting NASA engineers in their efforts to develop a supersonic aircraft that will produce a soft “thump” in place of a disruptive sonic boom.

New Airplane Wing Assembled from Tiny Identical Pieces

TBMG-3527710/01/2019

A radically new kind of airplane wing, assembled from hundreds of tiny identical pieces, can change shape to control the plane’s flight, and could provide a significant boost in aircraft production, flight, and maintenance efficiency. The new approach to wing construction could afford greater flexibility in the design and manufacturing of future aircraft.

Basic Composite Repair Technician Certification Standard

ARP6262A (Current)09/10/2019

It is recognized that the structural integrity of repaired composite structures depends upon the capabilities of the individuals who are responsible for performing the repairs. This document is intended to address repairs of composite structure regardless of the type of structure such as marine, wind turbine, automotive, aircraft, or other applications. This certification standard establishes the minimum requirements for training, examining, and certifying composite structure repair personnel. It establishes criteria for the certification of personnel requiring appropriate knowledge of the technical principles underlying the composite structural repairs they perform. Persons certified under this document may be eligible for licensing or certification/ qualification by an appropriate authority, in addition to this industry accepted basic composite repair technician certification. Persons who successfully complete the requirements of this certification standard are considered to be able

AMS CACRC Commercial Aircraft Composite Repair Committee

A Parametric Study on the Thermodynamic Characteristics of DBD Plasma Actuation and Its Potential for Wind Turbine Icing Mitigation

2019-01-203106/10/2019

Wind turbine icing represents the most significant threat to the integrity of wind turbines in cold weather. Ice formation on wind turbine blades was found to cause significant aerodynamic performance degradation, resulting in a substantial drop in energy production. Recently developed Dielectric barrier discharge (DBD) plasma-based anti-/de-icing systems showed very promising effects for aircraft icing mitigation. In this present study, DBD plasma-based anti-/de-icing systems were employed for wind turbine icing mitigation. First, a comprehensive parametric study is conducted to investigate the effects of various DBD plasma actuation parameters on its thermodynamic characteristics. An infrared (IR) thermal imaging system is used to quantitatively measure the temperature distributions over the test plate under various test conditions. DBD plasma actuators are embedded over the surface of a DU91-W2-250 wind turbine blade model, and a series of experiments were conducted by using the

Kolbakir, Cem, Gao, Linyue, Liu, Yang, Hu, Hui

Rotary Electrical Contact

TBMG-3462006/01/2019

Researchers have developed a fundamentally new type of rotary electrical contact that addresses the two limitations of conventional brush/slip ring technology: 1) short operating lifetime due to sliding-contact wear, and 2) electrical arcing associated with contact bounce.

Fine Tuning the SST k − ω Turbulence Model Closure Coefficients for Improved NASCAR Cup Racecar Aerodynamic Predictions

2019-01-064104/02/2019

Faster turn-around times and cost-effectiveness make the Reynolds Averaged Navier-Stokes (RANS) simulation approach still a widely utilized tool in racecar aerodynamic development, an industry where a large volume of simulations and short development cycles are constantly demanded. However, a well-known flaw of the RANS methodology is its inability to properly characterize the separated and wake flow associated with complex automotive geometries using the existing turbulence models. Experience suggests that this limitation cannot be overcome by simply refining the meshing schemes alone. Some earlier researches have shown that the closure coefficients involved in the RANS turbulence modeling transport equations most times influence the simulation prediction results. The current study explores the possibility of improving the performance of the SST k − ω turbulence model, one of the most popular turbulence models in motorsports aerodynamic applications, by re-evaluating the values of

Fu, Chen, Bounds, Charles, Uddin, Mesbah, Selent, Christian

The Review of Present and Future Energy Structure in China

2019-01-061204/02/2019

Both the economy and energy demand increase rapidly in China. The government is facing severe problems from energy security, carbon emissions and environmental issues. The past trends and future plans of energy will have great influence on the transportation, construction and industry development. This paper summarizes the present and future energy structure in China. Conventional fossil energy, nuclear energy and renewable energy are all included. Electricity will account for more proportion in total energy consumption in the future, and the structure of electricity will be cleaner. That will promote the development of electric vehicles and the transformation of China’s automotive industry. The optimization of energy structure will accelerate the low-carbon development in China. China’s energy development will enter a new stage from the expansion of total quantity to the upgrading of quality and efficiency. In order to realize the Paris Climate Agreement, China must steadily control

Liu, Feiqi, Zhao, Fuquan, Hao, Han, Liu, Zongwei

Plasma Generator Using Spiral Conductors

TBMG-3370302/01/2019

NASA's Langley Research Center has developed a patented SansEC sensor technology for use in many different areas, including tall structures and wind turbines. The SansEC technology is a proven wireless sensing platform capable of measuring the electrical impedance of physical matter in proximity to the sensor based on a change in its resonance response. The SansEC sensor also exhibits a unique characteristic to disperse the lightning strike current to help mitigate lightning damage. In a turbine blade application, an array of SansEC sensors will cover the surface area of the composite blade, providing both lightning mitigation and damage sensing. NASA Langley is seeking industrial partners/licensees to commercialize this technology. The research team at NASA Langley is available to assist with further development.

Material Removes Ice Buildup Without Power or Chemicals

TBMG-3368002/01/2019

From airplane wings, to overhead power lines, to the giant blades of wind turbines, a buildup of ice can cause problems ranging from impaired performance all the way to catastrophic failure. Preventing that buildup usually requires energy-intensive heating systems or chemical sprays that are environmentally harmful.

Synthesis and Development of Polyurethane Coatings Containing Fluorine Groups for Adhesive Applications

TBMG-3322911/01/2018

Accumulation of insect strikes on the leading edge of airplane wings is a more serious problem than one might realize. Depending on the magnitude, such accumulation changes the aerodynamic characteristics of the wing, causing a change from laminar to turbulent flow and resulting in decreased lift and increased drag. Overall, this also results in decreased fuel efficiency. Proposed solutions include elastic surfaces, coatings, soluble films, and fluid covers. Coatings offer an advantage over other strategies due to ease of application, potentially negligible weight penalty, reduced environmental concerns, better economics, and continual function throughout the flight profile.

Water-Based Battery Stores Solar and Wind Energy

TBMG-3247608/01/2018

Wind and solar energy generation creates challenges, since the Sun only shines by day, and sometimes the wind doesn't blow. Another variability is surges of demand on the grid. On a hot day when air conditioning is in use, utilities must have load-balancing strategies to meet peak demand. A water-based battery was developed that could provide a cheap way to store wind or solar energy generated when the Sun is shining and wind is blowing so it can be fed back into the electric grid and be redistributed when demand is high.

Mobile Power Distribution System

TBMG-2969007/01/2018

Mobile or transportable power supply and distribution systems are needed for various types of work that require electrical power in a field or outdoor environment — such as construction and environmental remediation projects — to power tools, lights, and other devices. For many projects, this need is met by either running a power line from the nearest available power source (referred to as shore power) or through use of a generator. While generators provide a source of electrical power in a field environment, the limited number and type of electrical outlets on the generator and the preset configuration of a given generator may be insufficient for the operation.

“Intelligent” Rotor Blades React Quickly to Changing Conditions

TBMG-2900506/01/2018

The giant rotor blades are one central part of a wind turbine. Researchers developed a rotor blade that makes more efficient use of large fluctuations in wind strength using a passive bend-twist coupling (BTC) that adapts continuously to the wind forces acting on the rotor blade. When the wind loads become too high, the coupling reduces the forces affecting the structure.

Nano-Sized Actuator Lifts Many Times its Weight

TBMG-2903706/01/2018

Actuators are used in a wide variety of electromechanical systems and in robotics, in applications such as steerable catheters, aircraft wings that adapt to changing conditions, and wind turbines that reduce drag.

Design and Optimization of Composite Horizontal Axis Wind Turbine (Hawt) Blade

2018-01-103404/03/2018

Wind energy is clean and renewable source of energy that is an attractive alternative to non-conventional sources of energy. Due to rapid increase in global energy requirements, this form of energy is gaining its share of importance. Unlike nuclear power or tar sand oils, wind energy does not leave a long-term toxic legacy. Using MATLAB algorithms, multi-optimization of wind turbine design can be achieved. Therefore, an aerodynamic mathematical model is developed to obtain the optimal chord length and twist angle distribution along the blade span. Further, a promising generic blade design is used to initialize a detailed structure optimization wherein leading edge panel (LEP), Spar cap, Shear web, Trailing edge panel (TEP) reinforcement are sized using composite laminates so that the blade is according to the intended design standard. Initially blade airfoils are analyzed on 2D platform and then the results are used to construct 3D model of Horizontal Axis Wind Turbine (HAWT) blade

Brella, Rohan, Sehgal, Mayank, Kumar, Naveen

Wind Turbine Blade Testing System Using Base Excitation

TBMG-2817401/01/2018

Wind turbine designers are working to provide blade designs that allow a turbine connected to the blades or rotor to effectively convert wind into electricity. The blades must also be designed properly to withstand inertial forces, aerodynamic forces, and structural forces to provide a relatively long service life and safe operation. Like all rotating machines, wind turbines are generators of fatigue, and every revolution of their components, including the turbine blades, produces a load or fatigue cycle, with each of these cycles causing a small, finite amount of damage that eventually may lead to fatigue cracks or other failures.

Fluorinated Alkyl Ether Epoxy Resin Compositions and Applications Thereof

TBMG-2816801/01/2018

NASA Langley Research Center has developed fluorinated alkyl ether-containing epoxies designed as an anti-insect coating. The robust and durable coating was developed to improve aircraft efficiency, but the coating could be useful in a variety of applications where reduction of insect residue adherence is desirable, such as in automotive and wind energy industries.

External Aircraft Noise Reduction Liners

TBMG-2720407/01/2017

NASA Langley Research Center, in collaboration with Boeing and Lockheed Martin, has developed a new external acoustic liner for aircraft noise reduction. While the acoustic liner can be placed on any external aircraft surface, one attractive application is for open-rotor noise reduction. Airframe manufacturers are considering open rotor engines for future aircraft designs as they provide significant fuel savings. However, open rotor engines have no nacelle and thus, do not allow the use of conventional nacelle liners for noise abatement. This technology strategically places acoustic liners on the external surface of the aircraft to reduce such engine noise.

Data Optimization Technology Helps Wind Farm Operator Examine Costs

TBMG-2719007/01/2017

Seeq Seattle, WA For more info click

Residual Mode Filters

TBMG-2531809/01/2016

NASA has developed a unique control algorithm and synthesis method that uses a system’s output to modify control inputs to cause the system to track a reference model or a fixed value in the presence of unmodeled system dynamics, varying operating environments, and unpredictable disturbances. The unique feature of this algorithm is the ability to instantaneously adapt the system according to its output, rejecting persistent disturbances, and ultimately improving the system’s performance. This makes the controller ideally suited for applications where there are unknown modeling parameters or uncertain operating environments. Many aerospace systems must function in unknown or highly variable environments. This technology allows the system to achieve its objectives in these types of unpredictable environments. In comparison to current adaptive controller technologies, the addition of residual mode filters allows operation when flexible modes are present that could inhibit the controller

Flow Simulation and Theoretical Investigation on Aerodynamics of NACA-2415 Aerofoil at Low Reynolds Number

2015-01-257609/15/2015

The Aerofoil theory along with its design has integrated itself into the vast areas of applications ranging from Automobile, Aeronautical, Wind Turbine, Micro-Vehicles, UAVs applications. In this paper, knowing the intricacy of the airfoil's applications, A MATLAB Code for NACA-2415 Airfoil is developed and a Model with dimensions c=180mm, w=126mm, tmax=27mm is generated. The model is then subjected to Flow Simulation with various input parameters: Reynolds Numbers taken are- (REN-1) 105 and (REN-2) 2×105 [Laminar External Flow], Angles of attack taken are-0°, 4°, 8°, 12°. The pressure and velocity distribution along the airfoil sketch curve are graphed qualitatively, emphasizing on the flow separation leading to the transition from laminar to turbulent flow. The various aerodynamics characteristic curves for coefficient of pressure, coefficient of lift and coefficient of drag are plotted against different angle of attacks for REN-1 and REN-2. The results were found in good harmony

Kumar, Vasu, Tomar, Vishvendra, Kumar, Naveen, Jain, Samarth

SPH Simulation of Rivulet Dynamics on Surfaces with Various Wettabilities

2015-01-900509/01/2015

Rivulet dynamics is involved in different scientific problems and industrial applications from production of microchips, to rain flow on structural systems such as wind turbine blades and aircraft wings. In the latter case for example, rivulet flow leads to accumulation of ice on airfoil surface that may affect the aircraft performance. Hence, understanding the dynamics of rivulets is important in solving various scientific problems. In this paper the results of a numerical simulation based on smoothed particle hydrodynamic (SPH) method will be reported on dynamics of rivulets under the effect of various air shear speeds and different surface morphologies. The simulation results will be compared and validated with experiments to shed more lights in understanding the mechanism of shear driven rivulet flow on solid substrates.

Moghtadernejad, Sara, Jadidi, Mehdi, Dolatabadi, Ali, Esmail, Nabil

Getting it RIGHT with composites

15MEIP09_0409/01/2015

With composites now a mainstay in most new aircraft designs, the engineering emphasis has switched from understanding if they work to thinking through the most efficient way to manufacture them, such as using design-for-manufacturing software. “Composite design and analysis is a highly integrated activity,” said Chris Gear, Chief Technology Officer & Senior Technical Fellow for GKN Aerospace. He noted that how composite material is placed, how it moves, how it cures, and the quality and conformance of the product are all inter-related. All of these factors are considered in the final release of the data for manufacturing, he said, aided by design-for-manufacturing (DFM). Complicating manufacturing optimization is the very nature of advanced composites, requiring a unique design process, unlike isotropic, homogenous metal. Controlling fiber orientation and number of layers of fiber embedded in a plastic matrix is vital for its performance. Initial CAD definitions that specify the outer

Morey, Bruce

Getting It Right with Composites

15AERP06_0206/01/2015

With composites now a mainstay in most new aircraft designs, the engineering emphasis has switched from understanding if they work to thinking through the most efficient way to manufacture them, such as using design-for-manufacturing software. “Composite design and analysis is a highly integrated activity,” said Chris Gear, Chief Technology Officer & Senior Technical Fellow for GKN Aerospace. He noted that how composite material is placed, how it moves, how it cures, and the quality and conformance of the product are all interrelated. All of these factors are considered in the final release of the data for manufacturing, according to him, aided by design-for-manufacturing (DFM). Complicating manufacturing optimization is the very nature of advanced composites, requiring a unique design process, unlike isotropic, homogenous metal. Controlling fiber orientation and number of layers of fiber embedded in a plastic matrix is vital for its performance. Initial CAD definitions that specify

Morey, Bruce

Getting It Right with Composites

TBMG-2229506/01/2015

"Composite design and analysis is a highly integrated activity,” said Chris Gear, Chief Technology Officer & Senior Technical Fellow for GKN Aerospace. He noted that how composite material is placed, how it moves, how it cures, and the quality and conformance of the product are all interrelated. All of these factors are considered in the final release of the data for manufacturing, according to him, aided by design-for-manufacturing (DFM).

Bootstrapping and Separable Monte Carlo Simulation Methods Tailored for Efficient Assessment of Probability of Failure of Structural Systems

2015-01-042004/14/2015

There is randomness in both the applied loads and the strength of systems. Therefore, to account for the uncertainty, the safety of the system must be quantified using its reliability. Monte Carlo Simulation (MCS) is widely used for probabilistic analysis because of its robustness. However, the high computational cost limits the accuracy of MCS. Smarslok et al. [2010] developed an improved sampling technique for reliability assessment called Separable Monte Carlo (SMC) that can significantly increase the accuracy of estimation without increasing the cost of sampling. However, this method was applied to time-invariant problems involving two random variables. This paper extends SMC to problems with multiple random variables and develops a novel method for estimation of the standard deviation of the probability of failure of a structure. The method is demonstrated and validated on reliability assessment of an offshore wind turbine under turbulent wind loads. The results show the method

Jehan, Musarrat, Nikolaidis, Efstratios

Pumped Subsea Energy Storage

TBMG-21632

03/01/2015

A local energy source is desired for near-shore and offshore applications. Gas generators, diesel generators, and long-length submerged power cables tend to be expensive. A proposed solution is to use offshore wind with some type of energy storage mechanism for up to 1 GW-h. Energy storage in batteries is too expensive and massive, and subsea compressed air energy storage (CAES) has not been proven for very deep depths. Furthermore, CAES involves very great temperature changes that result in large inefficiencies.

2014 Create the Future Design: Sustainable Technologies Category Winner

TBMG-2098711/01/2014

Dipul Patel, Yoel Kelman, Nick Lancaster, Shawn Rose, and Brian Bowen ecovent Systems Boston, MA

Tethered Vehicle Control and Tracking System

TBMG-1991506/01/2014

This innovation can control the flight of a tethered vehicle, in an airborne wind energy (AWE) generation system, through the use of a pan-tilt platform and a visible spectrum digital camera, combined with tracking and control software running on a standard PC.

Mars Technologies Spawn Durable Wind Turbines

TBMG-19536

05/01/2014

In the early 1990s, NASA was planning for an extended stay on Mars, and scientists at Ames Research Center were concentrating efforts on creating a complete ecological system to sustain human crew-members during their time on the Red Planet. The group started looking at maximizing energy efficiency and alternative methods to make power on a planet that is millions of miles from Earth. They turned to a hybrid concept combining two renewable sources: wind and solar power technologies. Large surface temperature swings on Mars produce windy conditions; extreme examples are the frequent dust storms that can block nearly all sunlight.