Browse Topic: Cooperative programs
America Makes, the National Additive Manufacturing Innovation Institute, announced the 15 awardees of its second call for additive manufacturing (AM) applied research and development projects. Driven by the National Center for Defense Manufacturing and Machining, America Makes will provide $9 million in funding toward these projects with $10.3 million in matching cost share from the awarded project teams for total funding worth $19.3 million. The projects are expected to commence in early Spring.
Engineering VP Scott Kunselman talks about working with Fiat, taking the lead in vehicle electrification, and putting the mojo back into Chrysler's product-development team. After 25 years of riding one of the auto industry's wildest roller coasters, Scott Kunselman now works on comparatively stable ground. More relaxed it's not, however. As Chrysler's Senior Vice President- Engineering, he's charged with integrating his company's product-development activities with those of Fiat. That means launching more than 20 new or significantly revamped North American models, consolidating four vehicle platforms, and working with his colleagues in Turin to commonize three other platforms, along with billions worth of related systems and components.
For companies that do not need NASA-developed technology or advanced test facilities but still want to leverage some of the brain power of NASA’s engineering teams to solve a design problem in their product, NASA funds the Space Alliance Technology Outreach Program (SATOP). Administered by Bay Area Houston Economic Partnership, SATOP is a cooperative program among Florida, New Mexico, New York, and Texas that brings together more than 55 space companies, universities, colleges, and NASA centers to make NASA expertise available to small businesses.
As the power density of advanced turboshaft engines increases, the need for new materials capable of higher operating temperatures, such as ceramic matrix composites (CMC), is critical for turbine hot section static and rotating components. Such advanced materials have significantly increased temperature capability vs conventional super alloy metal blades and enable longer life, reduced emissions, growth margin, reduced weight, and increased performance. This paper describes a cooperative program funded by the Army Aviation Applied Technology Directorate and General Electric Aircraft Engines (GEAE) to design, develop and fabricate CMC Power Turbine (PT) airfoils for application in advanced turboshaft engines such as GEAE’s Advanced Affordable Turbine Engine (AATE). During the initial stages of this program, trial dovetail, blade and witness panel coupons are fabricated and tested. In the final stages of the program, engine configuration PT blades are fabricated and undergo overspeed, HCF, impact and rub validation testing.
A cooperative program was conducted between the FAA, U.S. Navy, NASA, and the U.S. Air Force to evaluate crack detection techniques in a seeded fault engine test. The first stage fan of a TF41 engine with a seeded fault was run in a full scale engine test facility. Various disk crack detection systems were installed on the disk and monitored real time. Post-engine-test cycles were accumulated on the TF41 disk in a spin pit to further measure crack growth and disk strain. The crack in the TF41 first stage fan disk grew during the engine test, but significantly less than that predicted from fracture mechanics analysis. Techniques to detect disk crack using center of mass shift seemed feasible in the engine test environment. Techniques to detect disk crack using blade deflections was not effective in this test due to blade wander.
Higher power density requirements for future turboshaft engines necessitate higher pressures and operating temperatures. This results in higher shaft speeds and the need for smaller shaft diameters to reduce disk bore stresses. Higher rotational speed and smaller shaft diameters lower the critical speed of the shafts relative to the operating speed of the engine, resulting in supercritical operation. Preliminary results of a cooperative program to design, develop and fabricate a titanium matrix composite (TMC) low pressure turbine (LPT) shaft for application in a turboshaft engine, and to demonstrate improved frequency characteristics of this shaft relative to a conventional all-metallic shaft, were presented in a previous paper. This paper will focus on the design, test results and metallographic analysis of the TMC barrels and shafts manufactured during the program. Four TMC barrels and two LPT shafts were manufactured and subjected to an array of thermal-mechanical tests. The results of the testing indicated that a defect free TMC barrel has significantly higher mechanical properties than required for the selected engine application requirements. Modal tests of the fabricated shaft verified analytical predictions of the critical speed benefits.
The wind tunnel test of HART II (Higher Harmonic Control Aeroacoustic Rotor Test), performed in October 2001 in the Large Low-Speed Facility (LLF) of the German-Dutch Wind-tunnel (DNW), is part of an international cooperative program by the German DLR, French ONERA, DNW, NASA Langley and the US Army Aeroflightdynamics Directorate (AFDD). The main objective of the program is the investigation of rotor wake and its influence on rotor blade-vortex interaction (BVI) noise with and without higher harmonic pitch control (HHC). For blade position and deflection measurements the Stereo Pattern Recognition (SPR) technique was used for the first time. This technique is based on a 3-dimensional reconstruction of visible marker locations by using stereo camera images. An evaluation of these images leads to the spatial position of markers which are attached to each of the four blades and to the bottom of the fuselage and thus to the blade motion parameters in flap, lead-lag and torsion. In this paper the different analysis methods and post-processing of SPR data are presented and the advantages, drawbacks and the potential of this technology are shown.
A report describes the completed first phase of a NASA/industry cooperative program of research on metal-matrix composites (MMCs) as lightweight, strong, high- temperature-resistant materials for use in future aircraft engines. The first phase of the research included assessment of life- and fracture-prediction methods, determination of fracture strengths and fatigue lives, and experiments in nondestructive evaluation. The metal-matrix composite specimens used in these studies were rings made of silicon-carbide-based fibers in a titanium-alloy matrix. The particular composite material was chosen because extensive data on the material were already available and the material is representative of composites that would be used in aircraft engines. Five fracture- and life prediction analysis methods were applied to the rings; their predictions were compared with each other and with experimental data on fracture of the rings. Manufacturing defects prevented the researchers from conducting planned cyclic tests. Fatigue-life predictions ranged from 1,000 to 15,000 cycles. Fracture-stress predictions were less scattered, ranging from 25 to 40.1 kpsi (172 to 276 MPa). Low-resolution x-ray computed tomography proved to be an effective non-destructive evaluation technique.
Higher power density requirements for future turboshaft engines necessitate higher pressures and operating temperatures. This results in higher shaft speeds and the need for smaller shaft diameters to reduce disk bore stresses. Higher rotational speed and smaller shaft diameters lower the critical speed of the shafts relative to the operating speed of the engine, resulting in supercritical operation. This paper describes the results of a cooperative program funded by the Army Aviation Applied Technology Directorate, General Electric Aircraft Engines and Honeywell Engines, Systems and Services to design, develop and fabricate a titanium matrix composite (TMC) low pressure turbine (LPT) shaft for application in a turboshaft engine and to demonstrate improved frequency characteristics of this shaft relative to a conventional all metallic shaft.
In a major cooperative program within the existing US-German and US-French Memoranda of Understanding/Agreements (MOU/MOA), researchers from German DLR, French ONERA, NASA Langley, and the US Army Aeroflightdynamics Directorate (AFDD) conducted a comprehensive experimental program in October 2001 with a 40% -geometrically and aeroelastically scaled model of a BO-105 main rotor in the open-jet anechoic test section of the German-Dutch Windtunnel (DNW). This international cooperative program carries the acronym HART-II (Higher harmonic control Aeroacoustics Rotor Test). The main objective of the program is to improve the basic understanding and the analytical modeling capabilities of rotor blade-vortex interaction noise with and without higher harmonic pitch control (HHC) inputs, particularly the effect of rotor wakes on rotor noise and vibration. Comprehensive acoustic, rotor wakes, aerodynamic, and blade deformation data were obtained with pressure-instrumented blades. The test plan has been concentrated on measuring extensive rotor wakes with a 3-component Particle Image Velocimetry (PIV) technique, along with measurements of acoustics, blade surface pressures, and blade deformations. The prediction team with researchers from DLR, ONERA, NASA-Langley and AFDD was actively involved with the pre-test activities to formulate a test plan and measurement areas of the PIV technique. The prediction team predicted all the test results in advance before performing the wind tunnel test. This was done to obtain the best quality of test data, to improve the speed of measurements, and to determine the necessary measurement information for code validation. In this paper, an overview of the HART-II program and some representative measured and predicted results are presented.
This paper describes a fuzzy logic (FL) approach to the design, implementation, and tuning of an expert knowledge-based TCS for a four-wheel drive vehicle. Military and commercial mutual interests in TCS technology are highlighted as the underlying motivation for this government, industry, academia cooperative program. Coordinated parallel efforts to model the TCS equipped vehicle and to perform basic on-vehicle TCS experiments provided additional information to augment the knowledge obtained from a study of commercial TCSs and the tire traction literature. The general traction control problem is discussed along with the hardware considerations for a TCS. The design and integration of the resulting FL-based TCS are described along with a representative sample of the test results documenting the system's performance.
In a major cooperative program between U.S. Government agencies (represented by the U.S. Army Aeroflightdynamics Directorate and NASA Ames and Langley Research Centers) and United Technologies Corporation (represented by United Technologies Research Center and Sikorsky Aircraft Division), a 1/6 geometrically and aeroelastic ally scaled UTC model helicopter rotor was tested in the open-jet anechoic test section of the Duits-Nederlandse Windtunnel in the Netherlands. As the fourth entry under the Aerodynamic and Acoustic Testing of Model Rotors Program, several comprehensive acoustic and aerodynamic databases were obtained relating the important aerodynamic phenomena to both the near- and far-field acoustic radiation. In particular, high speed impulsive noise and blade-vortex interaction are of primary interest. This paper provides an initial summary of the acoustic measurements acquired for some of the different configurations tested. A review of the baseline swept tip rotor acoustic characteristics in the regimes of high speed forward flight, where high speed impulsive noise dominates, and low speed descent, where severe blade vortex interaction noise occurs, is presented. The trends of these primary noise sources are studied as the first step in validating the data for release and application.
In a major cooperative program between the U.S. Army Aeroflightdynamics Directorate (AFDD), the NASA Ames and Langley Research Centers, the United Technologies Research Center (UTRC), and the Sikorsky Aircraft Division of United Technologies, a geometrically and aeroelastically scaled model of a Sikorsky helicopter rotor was tested in the open-jet anechoic test section of the Duits-Nederlandse Windtunnel (DNW) in the Netherlands. As the fourth entry under the Aerodynamic and Acoustic Testing of Model Rotors (AATMR) Program, comprehensive acoustic, aerodynamic, dynamic, and performance data were obtained for a baseline pressure-instrumented swept tip rotor and for three additional configurations, including a main rotor/tail rotor combination and a main rotor with a BERP-planform tip. The primary objectives were to generate an extensive airload and acoustic data base for the baseline rotor and to examine the relation between the blade pressures and the near- and far-field acoustic radiation. Considering the variety of configurations and measurements, and the number and extent of the sound and pressure measurement locations, this was the most comprehensive model rotor test yet conducted. This paper describes the UTC model scale rotors, the DNW wind tunnel, the AFDD Rotary Wing Test Stand (RWTS), the UTRC and AFDD aerodynamic and acoustic data acquisition systems, and the scope of the test matrices. It also provides an introduction to the test results. The data is expected to improve understanding of rotor aerodynamics, acoustics, and dynamics, and lead to enhanced analytical methodology and design capabilities for the next generation of rotorcraft.
This is the fourth in a series of tests conducted as a Coordinating Research Council cooperative program to evaluate the measurement methods used to analyze diesel exhaust gas constituents. A multi-cylinder engine was circulated to 15 participants who measured emissions at three engine conditions. All 15 participants measured nitric oxide and carbon monoxide with several laboratories measuring nitric oxide by both NDIR (Non-Dispersive Infrared) and CHEMI (Chemiluminescence). Some participants also measured carbon dioxide, nitrogen dioxide, oxygen, and unknown span gases. The test results are compared with the Phase III cooperative tests which involved simultaneous measurement of emissions by participants. The precision of the results was poorer in Phase IV than Phase III.
This paper presents some results of wind tunnel tests and analytical studies of a Grumman aircraft design called HELICAT which features a prop rotor mounted in a tilting pod at each wing tip. The rotor incorporates an offset flapping hinge with positive (pitch reducing) delta-3. The test program was divided between evaluation of the Helicat prototype design and investigation of a "research" whirl flutter configuration. Most of this paper is devoted to the whirl flutter investigation. One case of blade flutter was encountered in the Helicat configuration; 83 cases of whirl flutter were obtained in the research configuration. Forward, backward, and bimodal whirl flutter were encountered. The parametric study of whirl flutter included variations in blade pitch-flap coupling, hinge offset, rotor pod pitch and yaw stiffness, and damping. Analytical correlation studies showed good agreement with the test data. Testing of this semi-span dynamically similar model was performed in the 16-foot Transonic Dynamics Tunnel at NASA, Langley, under a NASA/Grumman cooperative program during the period 3 February through 8 April 1971.
A Coordinating Research Council cooperative program was conducted to evaluate the measurement methods used to analyze nitric oxide and carbon monoxide in diesel exhaust. Initially, a single-cylinder test engine was circulated among participants with poor results. Tests were then conducted at one site using a multicylinder diesel engine. Six organizations participated in the program. Exhaust analyses were conducted at steady-state engine conditions and on a 3 min cycle test. Span gases of unknown concentration were also analyzed. The participants results varied but averaged less than ±5% standard deviation both within (repeatability) and among (reproducibility) the instruments. The short cycle test was in good agreement with the steady-state measurements. No significant difference in the use of Drierite, nonindicating Drierite, or Aquasorb desiccants was evident in sampling system tests. The instrumentation and methods used in this study were satisfactory for conducting emission measurements of diesel exhaust.
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