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At least 127 records · Page 7

2020 System Optimization Awardee: Carter Wind Turbines

With support from the Competitiveness Improvement Project's System Optimization Award, Carter Wind Energy aims to lower the cost of distributed wind technology and expand deployment. To do so, the company will improve the cost-effectiveness and reliability of midsize wind turbines for remote, off-grid power applications, creating new wind energy deployment opportunities worldwide. This fact sheet provides an overview of Carter Wind Energy's project, how the company will achieve the goals of the award, and how the project fits within the overall Competitiveness Improvement Project.

CIP↗

2021 Component Innovation Awardee: Siva Powers America

Siva Powers America earned a Competitiveness Improvement Project (CIP) Component Innovation award that will enable the company to evolve its 250/50 wind turbine design, discontinue its existing 13.4-meter wind turbine blades, and develop new 14.4-meter blades. These longer blades, which have additional extenders at the hub, will increase the rotor diameter to 35 meters, allowing for improved energy production at sites with lower wind resources. A collaboration with the National Renewable Energy Laboratory (NREL) includes a redesign, build, and on-site structural test for the new prototype blades. This will ultimately allow Siva Powers America to pursue recertification of the SIVA 250/50 to meet international standards.

CIP↗

2021 Component Innovation Awardee: Windurance, LLC

Distributed wind turbine manufacturers seeking to enter the market are often hampered by two challenges: not enough capital and no specific expertise in developing certified electronic equipment. A harsh reality is that off-the-shelf power electronics are neither certified nor cost-effective. This lack of certified controller equipment in the distributed wind energy industry adds expense and impedes market penetration related to certification for individual wind turbines, wind system projects, and installations. Normally, these certification costs would be borne repeatedly by individual turbine manufacturers or developers on a model-by-model or project-by-project basis, resulting in cost and time delays as well as uncertainty and risk for project developers and prospective owners. Windurance seeks to eliminate these challenges by developing and obtaining third-party certification of a standardized wind turbine controller. This will facilitate development, certification, and production while supporting efficiencies not easily achievable by individual manufacturers. Windurance's Distributed Wind Industry Turbine Controller will enable manufacturers to apply proprietary turbine- specific configurations and functionality. When applicable, manufacturers can expand on a Windurance-provided software framework to add unique or proprietary functionality.

CIP↗

2021 Prototype Installation and Testing Awardee: XFlow Energy Company

XFlow Energy Company (XFlow Energy) aims to reduce the cost of wind energy by designing vertical-axis wind turbines (VAWTs), which have a cheaper blade manufacturing process and a mechanically simpler design than traditional wind turbines, among other cost-saving advantages. However, a lack of modeling or simulation tools that can predict the coupling between aerodynamic and structural forces poses a significant challenge to developers of VAWTs. Known as aeroelastic models, these are not just important design tools - they're critical for certifying VAWTs of 25 kilowatts (kW), which is the size of XFlow Energy's prototype wind turbine. Without certification, XFlow Energy will not be able to deliver an independently validated product to its customers, and those customers will not be eligible for state and federal incentives. An accurate aeroelastic model could provide less-conservative structural optimization tactics than are currently used, resulting in a wind turbine with lower capital costs.

CIP↗

2020 Component Innovation Awardee: Windurance LLC

Currently, there is no wind system power-conversion component available to wind turbine OEMs that is certified to applicable standards for use in the U.S. distributed wind energy market. Off-the-shelf industrial drives have features that are not needed by distributed wind OEMs and lack other features that would be valuable for the operation and control of wind turbine generating systems. In addition to adding costs for OEMs, these industrial drives increase uncertainty and risk for project developers and prospective owners. All of this presents barriers and increases costs for the development of distributed wind in the United States. With funding from CIP, Windurance plans to develop an industry-specific power-conversion component that will offer application-specific features at lower cost for distributed wind OEMs.

CIP↗

2022 Prototype Manufacture and Installation Awardee: Sonsight Wind

The Sonsight Wind 3.5-kilowatt (kW) prototype turbine is designed to compete with solar power, meeting energy needs for a wide range of smaller-scale applications, such as powering individual homes and irrigation systems on farms and ranches in remote areas. The technology's innovative high-torque, low-rotations-per-minute generator permits the use of longer blades that, at moderate wind speed sites, generate the energy of a 5-kW turbine with lower thrust forces than similarly rated turbines. The 3.5-kW turbine is projected to ofer greater durability at a signifcantly lower levelized cost of energy. Sonsight Wind advanced the development of the prototype with a previous Competitiveness Improvement Project (CIP) funding award.

competitiveness improvement project↗

Wind-Related Modification of Some Small Impact Craters on Mars

Inferred wind-related modifications of impact craters are observed in the vicinity of the Mare Pathfinder (MPF) site and in other regions of Mars. Mars Orbiter Camera (MOC) images show three types of inferred wind-modified morphologies for craters 0.3-1 km in diameter Such modifications could be related to seasonal variations of the strongest winds and a possible paleowind regime. Geomorphic mapping of Big Crater at the MPF shows evidence of former aeolian modification of the crater rim and interiors similar to smaller craters in the area. The morphologic patterns are in good agreement with the results from the Mars Regional Atmospheric Modeling Simulation (MRAMS) of topographically forced wind circulation and atmosphere surface interactions generated by flow over small craters. Simulations show that the maximum surface stress is on the downwind crater rim, consistent with inferred wind modification of the crater rim seen in MOC images. The trend of the Inferred paleowind regime at the MPF site cannot be explained by a change In the global atmospheric circulation resulting ~ from changes in Mars obliquity. We suggest that this wind regime could be associated with a regional meteorological pattern that is not modeled by global scale circulation, An alternative explanation is that Mars spin axis was in a different geographic position than it is at present.

Kuzmin, Ruslan O.↗

Small scale noise and wind tunnel tests of upper surface blowing nozzle flap concepts. Volume 1. Aerodynamic test results

The results and analyses of aerodynamic and acoustic studies conducted on the small scale noise and wind tunnel tests of upper surface blowing nozzle flap concepts are presented. Various types of nozzle flap concepts were tested. These are an upper surface blowing concept with a multiple slot arrangement with seven slots (seven slotted nozzle), an upper surface blowing type with a large nozzle exit at approximately mid-chord location in conjunction with a powered trailing edge flap with multiple slots (split flow or partially slotted nozzle). In addition, aerodynamic tests were continued on a similar multi-slotted nozzle flap, but with 14 slots. All three types of nozzle flap concepts tested appear to be about equal in overall aerodynamic performance but with the split flow nozzle somewhat better than the other two nozzle flaps in the landing approach mode. All nozzle flaps can be deflected to a large angle to increase drag without significant loss in lift. The nozzle flap concepts appear to be viable aerodynamic drag modulation devices for landing.

Renselaer, D. J.↗

The 13-inch magnetic suspension and balance system wind tunnel

NASA Langley has a small, subsonic wind tunnel in use with the 13-inch Magnetic Suspension and Balance System (MSBS). The tunnel is capable of speeds up to Mach 0.5. This report presents tunnel design and construction details. It includes flow uniformity, angularity, and velocity fluctuation data. It also compares experimental Mach number distribution data with computed results for the General Electric Streamtube Curvature Program.

Johnson, William G., Jr.↗

Status of aerial applications research in the Langley vortex research facility and the Langley full-scale wind tunnel

Small scale models of agricultural airplanes were tested and numerical methods were utilized to study interactions between the airplane wake and the dispersed spray and granular materials. Methods were developed to measure and predict dispersal transport and wake characteristics and dispersal techniques to obtain interactions more favorable to wide, uniform deposition patterns and reduced drift. In the full scale wind tunnel, full scale agricultural airplanes and dispersal systems for both liquid and solid applications were evaluated to improve aircraft aerodynamics and dispersal systems efficiency. The program status in these two facilities is reported with emphasis on wake interactions and dispersal systems research.

Jordan, F. L., Jr.↗

Wind profiles for Space Shuttle loads analysis

The small scale wind velocity perturbations in vertical wind profiles at Cape Kennedy, Florida were analyzed in order to derive information for simulations of space shuttle ascent through the perturbed atmosphere. The available statistical data does not permit specification of various aspects of idealized singularities and wavelike perturbations with a reasonable degree of confidence. The information developed as a result of the analysis described in Section 3 of this report is suitable for the further development of idealized models. The term perturbation is used instead of the more common term, gust. According to the conventional approach, a gust profile is calculated by applying a high pass digital filter to a Jimsphere profile; all the speeds in the filtered profile are defined as gusts. The high pass filtered profile is defined as a residual profile and the maximum residual in the vicinity of a specified reference height is defined as the gust. Gusts defined in this manner represent the perturbation peaks. A detailed discussion of the calculation of residual profiles and gusts is given. The meteorological coordinate system, the data sample, and Jimsphere profiles are also described. Recommendations and conclusions are presented.

Adelfang, S. I.↗

Investigating Tiltrotor Formation Flight via 1/48-Scale Wind Tunnel Experiment

This paper describes two small-scale wind tunnel tests conducted in the Army 7- by 10-Foot Wind Tunnel at NASA Ames Research Center. These tests featured two 1/48-scale V-22 models that were operated in a variety of simulated flight conditions including climb, descent, and level flight at various flight speeds and spatial separations. Forces and moments experienced by the trail aircraft were used to deduce the influence of the lead aircraft on the trail aircraft. Particle Image Velocimetry (PIV) data were collected to relate these forces and moments to features in the lead aircraft wake. In general, the roll moment on the trail aircraft is shown to be maximum when the aircraft are laterally offset by a full wingspan and the trail aircraft is vertically positioned so as to be in the wake of the lead aircraft. Furthermore, the roll moment is maximal when operating near 50 knots full-scale flight speed. Because the interaction persists far downstream and the vertical position of the wake is dependent on descent angle and flight speed, lateral separation has been determined to be the best means of avoiding adverse interactions between aircraft.

Romander, Ethan↗

Investigating Tiltrotor Formation Flight Via 1/48-Scale Wind Tunnel Experiment

This paper describes two small-scale wind tunnel tests conducted in the Army 7- by 10-Foot Wind Tunnel at NASA Ames Research Center. These tests featured two 1/48-scale V-22 models that were operated in a variety of simulated flight conditions including climb, descent, and level flight at various flight speeds and spatial separations. Forces and moments experienced by the trail aircraft were used to deduce the influence of the lead aircraft on the trail aircraft. Particle Image Velocimetry (PIV) data were collected to relate these forces and moments to features in the lead aircraft wake. In general, the roll moment on the trail aircraft is shown to be maximum when the aircraft are laterally offset by a full wingspan and the trail aircraft is vertically positioned so as to be in the wake of the lead aircraft. Furthermore, the roll moment is maximal when operating near 50 knots full-scale flight speed. Because the interaction persists far downstream and the vertical position of the wake is dependent on descent angle and flight speed, lateral separation has been determined to be the best means of avoiding adverse interactions between aircraft.

PIV (PARTICLE IMAGE VELOCIMETRY)↗

Distributed Wind Market Report: 2023 Edition

The annual Distributed Wind Market Report provides stakeholders with market statistics and analysis along with insights into market trends and characteristics for wind technologies used as distributed energy resources. This report presents the distributed wind market from 2003 through 2022. Installed capacity, deployment trends, customer types, incentives, policies, installed costs, performance, and the future outlook for the distributed wind market are the key topics included in the report.

17 WIND ENERGY↗

A Flight Dynamics Model for a Small Glider in Ambient Winds

In this paper we describe the equations of motion developed for a point-mass zero-thrust (gliding) aircraft model operating in an environment of spatially varying atmospheric winds. The wind effects are included as an integral part of the flight dynamics equations, and the model is controlled through the three aerodynamic control angles. Formulas for the aerodynamic coefficients for this model are constructed to include the effects of several different aspects contributing to the aerodynamic performance of the vehicle. Characteristic parameter values of the model are compared with those found in a different set of small glider simulations. We execute a set of example problems which solve the glider dynamics equations to find aircraft trajectory given specified control inputs. The ambient wind conditions and glider characteristics are varied to compare the simulation results under these different circumstances.

Beeler, Scott C.↗

A Flight Dynamics Model for a Small Glider in Ambient Winds

In this paper we describe the equations of motion developed for a point-mass zero-thrust (gliding) aircraft model operating in an environment of spatially varying atmospheric winds. The wind effects are included as an integral part of the flight dynamics equations, and the model is controlled through the three aerodynamic control angles. Formulas for the aerodynamic coefficients for this model are constructed to include the effects of several different aspects contributing to the aerodynamic performance of the vehicle. Characteristic parameter values of the model are compared with those found in a different set of small glider simulations. We execute a set of example problems which solve the glider dynamics equations to find the aircraft trajectory given specified control inputs. The ambient wind conditions and glider characteristics are varied to compare the simulation results under these different circumstances.

Beeler, Scott C.↗

The history of re-connection and the concept of the solar wind plasma with relatively small electrical conductivity

Petschek's 're-connection' model, aspiring to be universal, treated as a boundary problem meets unresolvable difficulties connected with impossibility to specify correctly boundary and initial conditions. This problem was incorrectly formulated. Hence, ineradicable logarithmic singularities occurred on the boundary surfaces. Attempts to eliminate them by incorporating the finite electrical conductivity are incorrect. This should lead to the change in the equation type, boundary condition type and in consequence to the change in solutions. Besides, the slow mode shocks cannot be driven by small internal source. As an alternative a new plasma concept is suggested. The state of fully ionized plasma in space depends completely on the entropy of the plasma heating source and on the process in which plasma is involved. The presumptive source of the solar wind creation - the induction electric field of the solar origin - has very low entropy. The state of plasma should be very far from the thermodynamic equilibrium. Debye's screening is not complete. The excitation of the powerful resonant self-consistent electric fields in plasma provides low electric conductivity. The MHD problems should be treated in frameworks of dissipative theories.

Chertkov, A. D.↗