Download or read book Helicopter Rotor Wake Geometry and Its Influence in Forward Flight Volume 1 Generalized Wake Geometry and Wake Effect on Rotor Airloads and Performance written by T. A. Egolf and published by . This book was released on 1983 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analytic investigation to generalize wake geometry of a helicopter rotor in steady level forward flight and to demonstrate the influence of wake deformation in the prediction of rotor airloads and performance is described. Volume 1 presents a first level generalized wake model based on theoretically predicted tip vortex geometries for a selected representative blade design. The tip vortex distortions are generalized in equation form as displacements from the classical undistorted tip vortex geometry in terms of vortex age, blade azimuth, rotor advance ratio, thrust coefficient, and number of blades. These equations were programmed to provide distorted wake coordinates at very low cost for use in rotor airflow and airloads prediction analyses. The sensitivity of predicted rotor airloads, performance, and blade bending moments to the modeling of the tip vortex distortion are demonstrated for low to moderately high advance ratios for a representative rotor and the H-34 rotor. Comparisons with H-34 rotor test data demonstrate the effects of the classical, predicted distorted, and the newly developed generalized wake models on airloads and blade bending moments. Use of distorted wake models results in the occurrence of numerous blade-vortex interactions on the forward and lateral sides of the rotor disk. The significance of these interactions is related to the number and degree of proximity to the blades of the tip vortices. The correlation obtained with the distorted wake models (generalized and predicted) is encouraging.

Download or read book Helicopter Rotor Wake Geometry and Its Influence in Forward Flight Volume 2 Wake Geometry Charts written by T. Alan Egolf and published by . This book was released on 1983 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wake Geometry Measurements and Analytical Calculations on a Small Scale Rotor Model written by Terence A. Ghee and published by . This book was released on 1996 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1984 with total page 1278 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Evaluation of a Flat Wake Theory for Predicting Rotor Inflow wake Velocities written by John C. Wilson and published by . This book was released on 1992 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA Technical Memorandum written by and published by . This book was released on 1992 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA Technical Paper written by and published by . This book was released on 1986 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA Army Rotorcraft Technology Volume 1 Aerodynamics and Dynamics and Aeroelasticity written by and published by . This book was released on 1988 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rotorcraft Dynamics 1984 written by and published by . This book was released on 1985 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Full Potential Flow Analysis with Realistic Wake Influence for Helicopter Rotor Airload Prediction written by T. Alan Egolf and published by . This book was released on 1987 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA SP written by and published by . This book was released on 1988 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wind tunnel Acoustic Results of Two Rotor Models with Several Tip Designs written by Ruth McVoy Martin and published by . This book was released on 1986 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book AIAA 84 2255 AIAA 84 2299 written by and published by . This book was released on 1984 with total page 618 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Journal of Aircraft written by and published by . This book was released on 1997 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1984 with total page 1136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Full Potential Modeling of Blade Vortex Interactions written by Henry E. Jones and published by . This book was released on 1997 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study of the full-potential modeling of a blade-vortex interaction was made. A primary goal of this study was to investigate the effectiveness of the various methods of modeling the vortex. The model problem restricts the interaction to that of an infinite wing with an infinite line vortex moving parallel to its leading edge. This problem provides a convenient testing ground for the various methods of modeling the vortex while retaining the essential physics of the full three-dimensional interaction. A full-potential algorithm specifically tailored to solve the blade-vortex interaction (BVI) was developed to solve this problem. The basic algorithm was modified to include the effect of a vortex passing near the airfoil. Four different methods of modeling the vortex were used: (1) the angle-of-attack methods, (2) the lifting-surface method, (3) the branch-cut method, and (4) the split-potential method. A side-by-side comparison of the four models was conducted. these comparisons included comparing generated velocity fields, a subcritical interaction, and a critical interaction. The subcritical and critical interactions are compared with experimentally generate results. The split-potential model was used to make a survey of some of the more critical parameters which affect the BVI.

Download or read book Aeronautical Engineering written by and published by . This book was released on 1993 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA)