Download or read book Fluidic Control of Virtual Aerosurfaces written by and published by . This book was released on 2007 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: This experimental research has focused on modifying the global aerodynamic characteristics of lifting surfaces at cruise (low) angles of attack when the baseline flow is fully attached. Using hybrid actuators, trapped vorticity concentrations at the leading and trailing edges affect aerodynamic forces and moment without control surfaces. Hybrid actuators employ miniature obstructions with integrated synthetic jet actuators. Actuation on the pressure surface near the leading edge results in a substantial (up to 50%) reduction in pressure drag and total drag (29%) with virtually no loss in lift, leading to a higher lift to drag ratio. When the actuation is applied near the trailing edge, the effects are bi-directional changes in pitching moments, which can be continuously varied by controlling the actuation amplitude. Moreover, the same performance can be achieved at substantially reduced actuation power by exploiting transitory aerodynamic effects through pulse modulation. PIV studies of the flow in the vicinity of the actuators, in the boundary layer and the wake, were used in this investigation.
Download or read book Fluidic Virtual Aerosurfaces for Flow Control Applications written by and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research program has focused on a novel approach to the control of the aerodynamic performance of lifting surfaces by fluidic modification of their apparent aerodynamic shape, or virtual aerosurface shaping, This flow control approach emphasizes fluidic modification of the "apparent" aerodynamic shape of the surface with the objective of altering or prescribing the streamwise pressure gradient. Control is typically effected by the interactions of arrays of synthetic jet actuators with the cross flow that displace the local streamlines near the surface and thereby induces an "apparent" modification of the flow boundary. The operating frequency of the control jets is high enough so that the actuation period at least an order of magnitude lower than the relevant characteristic time scale of the flow. Therefore, the interaction domains between the control jets and the cross flow are quasi-steady and hence the induced aerodynamics forces are virtually time-invariant.
Download or read book Fluidic Virtual Aerosurfaces for Flow Control Applications written by Ari Glezer and published by . This book was released on 2004 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fluidic Virtual Aerosurfaces for Flow Control Applications written by and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research program has focused on a novel approach to the control of the aerodynamic performance of lifting surfaces by fluidic modification of their apparent aerodynamic shape, or virtual aerosurface shaping, This flow control approach emphasizes fluidic modification of the "apparent" aerodynamic shape of the surface with the objective of altering or prescribing the streamwise pressure gradient. Control is typically effected by the interactions of arrays of synthetic jet actuators with the cross flow that displace the local streamlines near the surface and thereby induces an "apparent" modification of the flow boundary. The operating frequency of the control jets is high enough so that the actuation period at least an order of magnitude lower than the relevant characteristic time scale of the flow. Therefore, the interaction domains between the control jets and the cross flow are quasi-steady and hence the induced aerodynamics forces are virtually time-invariant.
Download or read book Fluidic Based Virtual Aerosurface Shaping written by and published by . This book was released on 2004 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Control of Fluid Flow written by Petros Koumoutsakos and published by Springer. This book was released on 2010-04-06 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph presents the state of the art of theory and applications in fluid flow control, assembling contributions by leading experts in the field. The book covers a wide range of recent topics including vortex based control algorithms, incompressible turbulent boundary layers, aerodynamic flow control, control of mixing and reactive flow processes or nonlinear modeling and control of combustion dynamics.
Download or read book AVIA Adaptive Virtual Aerosurface written by and published by . This book was released on 2004 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: One can change the effective shape of a surface without any change in its physical moldlines through the transient injection of momentum to control unsteady flow phenomena, such as separation. This research program consists of a system level evaluation of the potential benefits and costs of active flow control as applied to UAVs for separation control, development of innovative actuator concepts, and proof-of-concept experiments showing aerodynamic effectiveness. System-level benefits include increased gust margin, reduced takeoff field length, increased payload capacity, and greater maneuverability. Actuator research has resulted in two major innovations: the use of pulsed/modulated waveforms to increase the effectiveness of synthetic jet actuators and the development of compact, high power, combustion-driven actuator modules. The general performance of the combustion actuators are characterized in isolation, embedded in cross-flows up to M=0.7, and integrated on a two-dimensional wing model. In addition, since conventional machining would not be suitable for low-cost, large volume production, a simpler, MEMS-based, batch fabrication.
Download or read book Control of Fluid Flow written by Petros Koumoutsakos and published by Springer Science & Business Media. This book was released on 2006-05-31 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph presents the state of the art of theory and applications in fluid flow control, assembling contributions by leading experts in the field. The book covers a wide range of recent topics including vortex based control algorithms, incompressible turbulent boundary layers, aerodynamic flow control, control of mixing and reactive flow processes or nonlinear modeling and control of combustion dynamics.
Download or read book Advanced Fluidic Controls for Integrated Propulsion Systems Part IV Demonstration of an Integrated Propulsion System Control at Simulated Flight Conditions Using Fluidic Control Techniques written by Ralph H. Pamperin and published by . This book was released on 1968 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feasibility of a fluidic control system for advanced integrated propulsion system control was demonstrated at simulated flight conditions in an altitude engine test cell. System studies were conducted using control and engine computer simulations to develop advanced propulsion system control modes. Using fluidic sensors and computational elements developed under this program, a fluidic integrated propulsion control system was mechanized and evaluated on a J95-GE-5 engine at the Air Force Aero Propulsion Laboratory at simulated Mach numbers and altitudes. Performance capability was demonstrated in the areas of start up, speed control, transient control, compressor stability control, turbine overtemperature control, overspeed control and variable engine geometry control. (Author).
Download or read book Fluidic Control Systems for Aerospace Propulsion written by and published by . This book was released on 1969 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Collection of Technical Papers 04 2614 04 2702 written by and published by . This book was released on 2004 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Aeronautical Journal written by and published by . This book was released on 2000 with total page 742 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 02 3155 02 3346 written by and published by . This book was released on 2002 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aerospace America written by and published by . This book was released on 2000 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Space Shuttle Missions Summary NASA TM 2011 216142 written by Robert D. Legler and published by www.Militarybookshop.CompanyUK. This book was released on 2011-09-01 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: Full color publication. This document has been produced and updated over a 21-year period. It is intended to be a handy reference document, basically one page per flight, and care has been exercised to make it as error-free as possible. This document is basically "as flown" data and has been compiled from many sources including flight logs, flight rules, flight anomaly logs, mod flight descent summary, post flight analysis of mps propellants, FDRD, FRD, SODB, and the MER shuttle flight data and inflight anomaly list. Orbit distance traveled is taken from the PAO mission statistics.
Download or read book 40th AIAA Aerospace Sciences Meeting Exhibit written by and published by . This book was released on 2002 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Launch Vehicle Design Process Characterization Technical Integration and Lessons Learned written by J. C. Blair and published by . This book was released on 2001 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
