Download or read book Model Tilt Rotor Hover Performance and Surface Pressure Measurement written by Chee Tung and published by . This book was released on 1990 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: A test of a small scale 3-bladed model rotor, with geometry typical of that used on tilt-rotor aircraft, was conducted in the Army Aeroflightdynamics Directorate's anechoic hover chamber. The purpose of this test was to determine the hover performance of the rotor and investigate the pressure distributions on a blade at various collective pitch angles and tip speeds. The measured pressures indicate that the rotor did not stall for high collective pitch angles up to theta sub c = 25 deg. This is clearly a three dimensional effect since two-dimensional theory predicts flow separation at these high angles. The flow near the trailing edge separated above theta sub c = 25 deg which caused a sharp increase in power. (edc).

Download or read book Performance and Pressure Data from a Small Model Tilt Rotor in Hover written by Lonnie Branum and published by . This book was released on 1997 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Surface Pressure Measurements at Two Tips of a Model Helicopter Rotor in Hover written by Robin Bryant Gray and published by . This book was released on 1980 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental and Computational Investigation of Tilt Rotor Hover Aeroacoustics written by David Rudolf Polak and published by Ann Arbor, Mich. : University Microfilms International. This book was released on 1996 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study to Interpret the Surface Pressure Measurements at the Tip of a Model Helicopter Rotor in Hover written by Robin Bryant Gray and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Preliminary Study of a Model Rotor in Descent written by and published by . This book was released on 2000 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Within a program designed to develop experimental techniques for measuring the trajectory and structure of vortices trailing from the tips of rotor blades, the present preliminary study focuses on a method for quantifying the trajectory of the trailing vortex during descent flight conditions. This study also presents rotor loads and blade surface pressures for a range of tip-path plane angles and Mach numbers. Blade pressures near the leading edge and along the outer radius are compared with data obtained on the same model rotor, but in open jet facilities. A triangulation procedure based on two directable laser-light sheets, each containing an embedded reference, proved effective in defining the spatial coordinates of the trailing vortex. When interrogating a cross section of the flow that contains several trailing vortices, the greatest clarity was found to result when the flow is uniformly seeded. Surface pressure responses during blade-vortex interactions appeared equally sensitive near the leading edge and along the outer portion of the blade, but diminished rapidly as the distance along the blade chord increased. The pressure response was virtually independent of whether the tip-path plane angle was obtained through shaft tilt or cyclic pitch. Although the shape and frequency of the pressure perturbations on the advancing blade during blade-vortex interaction are similar to those obtained in open-jet facilities, the angle of the tip-path plane may need to be lower than the range covered in this study.

Download or read book Effect of Planform Taper on Hover Performance of an Advanced AH 64 Model Rotor written by Henry L. Kelley and published by . This book was released on 1987 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental and Analytical Studies of a Model Helicopter Rotor in Hover written by F. X. Caradonna and published by . This book was released on 1981 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present study is a benchmark test to aid the development of various rotor performance codes. The study involves simultaneous blade pressure measurements and tip vortex surveys. Measurements were made for a wide range of tip Mach numbers including the transonic flow regime. The measured tip vortex strength and geometry permit effective blade loading predictions when used as input to a prescribed wake lifting surface code. It is also shown that with proper inflow and boundary layer modeling, the supercritical flow regime can be accurately predicted. (Author).

Download or read book An Assessment of the Capability to Calculate Tilting Prop rotor Aircraft Performance Loads and Stability written by Wayne Johnson and published by . This book was released on 1984 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book PERFORMANCE AND PRESSURE DATA FROM A SMALL MODEL TILT ROTOR IN HOVER NASA TM 110441 MAY 30 1997 written by and published by . This book was released on 1998* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hovering Measurements for Twin rotor Configurations with and Without Overlap written by George E. Sweet and published by . This book was released on 1960 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Assessment of the Capability to Calculate Tilting Prop rotor Aircraft Performance Loads and Stability written by and published by . This book was released on 1984 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of Small scale Rotor Hover Performance Data written by and published by . This book was released on 1990 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Zonal Procedure for Predicting the Hover Performance of a Helicopter Rotor written by Marvin Allyn Moulton and published by . This book was released on 1998 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Planform Geometry on Hover Performance of a 2 meter diameter Model of a Four bladed Rotor written by Arthur E. Phelps and published by . This book was released on 1986 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Assessment of the Capability to Calculate Tilting Prop Rotor Aircraft Performance Loads and Stability written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-25 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Calculated performance, loads, and stability of the XV-15 tilt rotor research aircraft are compared with wind tunnel and flight measurements, to define the level of the current analytical capability for tilting prop rotor aircraft, and to define the requirements for additional experimental data and further analysis development. The correlation between calculated and measured behavior is generally good, although there are some significant discrepancies. Based on this correlation, the analysis is assessed overall as being adequate for the design, evaluation, and testing of tilting prop rotor aircraft. A general assessment of the state of the art of tilt rotor predictive capability is given. Specific areas are identified where improvements in the capability to calculate performance, loads, and stability are desirable. Requirements for more accurate and detailed data which support the development of improved analytical models are identified as well. Johnson, W. Ames Research Center NASA-TP-2291, A-9411, NAS 1.60:2291 RTOP 505-42-11

Download or read book An Experimental Investigation of Vortex Stability Tip Shapes Compressibility and Noise for Hovering Model Rotors written by James L. Tangler and published by . This book was released on 1973 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: