Download or read book Evaluation of Wind Tunnel Data and Stress Analysis of Ribbon Parachutes written by Helmut G. Heinrich and published by . This book was released on 1975 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research group of the University of Minnesota concerned with aerodynamic deceleration directed by Prof. H.G. Heinrich is very interested in being engaged in investigations as specified in the work statement and outlined in the preceding technical description. Many years of experience with basic and applied research objectives as well as specialized equipment are available at the University. Parachute models will be fabricated in view of the most advanced status of model technique whenever such fabrication becomes necessary.
Download or read book Studies of Aerodynamics Dynamics and Stress Analysis of Ribbon Parachutes written by Sandia Corporation and published by . This book was released on 1976 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The following report describes the continuation of wind tunnel data evaluation as shown in Progress Reports 3 through 14 under Sandia Coropration Contract 63-2241 amd 02-4022, Ref 1 to 13. The data presented in this report are related to disreefing tests of a conical ribbon parachute with 140° included angle, concentric rings, and 25% geometric porosity. The data concerning the canopy profile and pressure distributions will be presented in chronological order starting at the time of disreefing and proceeding through inflation at various time intervals until steady state conditions for the fully inflated parachute are reached. The recorded and derived data recorded and derived data are used to obtain-force time histories which can be compared with a measured force-time recording. Also, so called radial force coefficients are derived which are based on the established canopy profiles and the related pressure data.
Download or read book Pressure and Profile Data of 20 Conical Ribbon Parachutes written by Helumt G. Heinrich and published by . This book was released on 1977 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Sandia Laboratories, Albuquerque, N.M., established wind tunnel data of 3 ft ribbon parachute models concerning canopy profiles, drag forces and pressure distribution. The data were analyzed at the University of Minnesota and resulted in presentations of drag coefficients, projected diameters and drag areas of reefed and unreefed and parachutes versus geometric porosity and suspension line length as well as in tables and graphs of canopy coordinates and related pressure distributions. Presssure integration about the canopy surfaces as given by the established coordinates provided drag forces which agreed satisfactorily with measured forces. Also, radial force coefficients of the various configurations were established. The results of this study are intended to serve as background information for related investigations such as studies concerning parachute dynamics, stress analysis, etc.
Download or read book Pressure and Canopy Profile Data of 20 Conical Ribbon Parachutes During Inflation written by H. G. Heinrich and published by . This book was released on 1977 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Sandia Laboratories, Albuquerque, N.M., established wind tunnel data of 3 ft ribbon parachute models concerning canopy profiles, drag forces and pressure distribution during the period of inflation. The data were analyzed at the University of Minnesota and resulted in presentations of canopy profile coordinates, drag areas and pressure distributions versus time. Pressure integration about the canopy surfaces as given by the established coordinates provided calculated areas which agreed satisfactorily with measured drag areas. Also, radial force coefficients of the various configurations were established. The results of this study are intended to serve as background information for related investigations such as studies concerning parachute dynamics, stress analysis, etc.
Download or read book Wind tunnel Investigation of Drag and Stabili Ty of Parachutes at Supersonic Speeds written by Nickolai Charczenko and published by . This book was released on 1964 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Parametric Wind Tunnel Study of Ribbon Parachutes written by D. F. McVey and published by . This book was released on 1975 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents the results of a series of wind tunnel tests conducted to define the effect of geometric porosity, reefing line length, and suspension line length on ribbon parachute drag. Twenty degree conical ribbon parachutes with nominal diameter of three feet, goemetric porosities from 15 to 30 percent and line lengths from 1.0 to 2.0 times the parachute nominal diameter were tested at dynamic pressures from 75 to 500 psf. Drag coefficients based on construction and average projected diameters are presented as a function of the independent variables. Data are also presented on parachute shape and inflated diameter. The wind tunnel drag coefficients are compared with data from free flight test of full scale parachutes and with othert wind tunnel data.
Download or read book Ribbon and Gliding Type Parachutes Evaluated in the 7 by 10 Foot Transonic Wind Tunnel written by Jonah Ottensoser and published by . This book was released on 1975 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experiment has been conducted in the NSRDC 7- x10-foot transonic tunnel for the Sandia Corporation to evaluate various parachute parameters. The experiment consisted of three main parts: the first phase evaluated the disreefing characteristics of the various parachutes as well as the drag forces before, during and after disreefing; the second phase measured the pressure distribution around the chute as well as the grag forces; and the fingal phase evaluated the disreefing and drag characteristics of gliding type parachutes. The free stream dynamic pressure varied from 65 to 500 psf.
Download or read book WInd tunnel Investigation of the Opening Characteristics Drag and Stability of Several Hemispherical Parachutes written by Stanley H. Scher and published by . This book was released on 1949 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation has been conducted to determine the opening characteristics of several hemispherical parachutes and to study the influence of the parachute design variables on these opening characteristics. The effects of design variables on the drag and stability characteristics of the parachutes were also evaluated.
Download or read book Parachute Recovery Systems written by Theo W. Knacke and published by . This book was released on 1992 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this manual is to provide recovery system engineers in government and industry with tools to evaluate, analyze, select, and design parachute recovery systems. These systems range from simple, one-parachute assemblies to multiple-parachute systems, and may include equipment for impact attenuation, flotation, location, retrieval, and disposition. All system aspects are discussed, including the need for parachute recovery, the selection of the most suitable recovery system concept, concept analysis, parachute performance, force and stress analysis, material selection, parachute assembly and component design, and manufacturing. Experienced recovery system engineers will find this publication useful as a technical reference book; recent college graduates will find it useful as a textbook for learning about parachutes and parachute recovery systems; and technicians with extensive practical experience will find it useful as an engineering textbook that includes a chapter on parachute- related aerodynamics. In this manual, emphasis is placed on aiding government employees in evaluating and supervising the design and application of parachute systems. The parachute recovery system uses aerodynamic drag to decelerate people and equipment moving in air from a higher velocity to a lower velocity and to a safe landing. This lower velocity is known as rate of descent, landing velocity, or impact velocity, and is determined by the following requirements: (1) landing personnel uninjured and ready for action, (2) landing equipment and air vehicles undamaged and ready for use or refurbishment, and (3) impacting ordnance at a preselected angle and velocity.
Download or read book Ribbon and Gliding Type Parachutes Evaluated in the 7 by 10 Foot Transonic Wind Tunnel written by Jonah Ottensoser and published by . This book was released on 1975 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experiment has been conducted in the NSRDC 7- x10-foot transonic tunnel for the Sandia Corporation to evaluate various parachute parameters. The experiment consisted of three main parts: the first phase evaluated the disreefing characteristics of the various parachutes as well as the drag forces before, during and after disreefing; the second phase measured the pressure distribution around the chute as well as the grag forces; and the fingal phase evaluated the disreefing and drag characteristics of gliding type parachutes. The free stream dynamic pressure varied from 65 to 500 psf.
Download or read book Experiments on the Thermal Performance of Ribbon Parachutes written by C. J. Scott and published by . This book was released on 1965 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental heat transfer studies were conducted on full scale ribbons of flat circular type parachutes having a geometric porosity of 20.5 percent. A pressurized subsonic wind tunnel served as the flow facility. The average approach flow velocity was 134 feet per second. The measurements were made in the Reynolds number range of one million to ten million, where the Reynolds number is based on the ribbon width of 2.1 inches and on the velocity and temperature of the flow in the slots between the ribbons. The pressure ratio applied to the ribbon was varied from 1.4 to 26.3. Using a transient energy balance, local and average heat transfer data were obtained and compared with available analyses.
Download or read book Wind tunnel Investigation of Inflation of Disk gap band and Modified Ringsail Parachutes at Dynamic Pressures Between 0 24 and 7 07 Pounds Per Square Foot written by Charles H. Whitlock and published by . This book was released on 1969 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exploratory wind-tunnel tests of the disk-gap-band and modified ringsail parachute configurations have been conducted at dynamic pressures between 0.24 and 7.07 lb/ft2 (11 and 339 N/m2). Both parachutes exhibited positive inflation characteristics over the range of the tests within technique limitations. The disk-gap-band configuration required less time and distance to inflate than the modified ringsail configuration did.
Download or read book Stress Measurements in a Ribbon Parachute Canopy During Inflation and at Steady State written by T. A. Konicke and published by . This book was released on 1981 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes the results of an experimental study of canopy stresses in a model ribbon parachute. The distribution of circumferential stress was measured during inflation and at steady state for different values of dynamic pressure. Testing was performed in the wind tunnel at the infinite mass condition. Omega sensors were used to measure stresses and were mounted in different ribbons along the gore centerline. It was found that the steady state stress had two maxima of about equal value. One maxima was near the skirt, the other half-way between the vent and skirt. The distribution of maximum stress during inflation was similar to the steady state distribution and the ratio of maximum stress during inflation to steady state stress ranged from 1.25 to 1.75 and was essentially independent of dynamic pressure. The spectral density of the steady state stress measured at several points on the canopy.
Download or read book Recovery System Design Guide written by E. G. Ewing and published by . This book was released on 1978 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of Parachute Forces and Canopy Pressure Distribution Measured in a Subsonic Wind Tunnel Under Infinite Mass Conditions written by Helmut G. Heinrich and published by . This book was released on 1972 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the purpose of parachute canopy stress analysis during the period of inflation, the pressure distribution measured on a ring-slot parachute model is related to the instantaneous parachute force. The correlation of pressure and force data is based on test results established at the Deutsche Forschungsanstalt fuer Luft-und Raumfahrt (DFLR), Braunschweig, Germany. The final pressure-force-time relationship incorporate individual as well as averaged test data. A fair agreement could be shown between measured forces and those obtained from numerical integration of differential pressure over the canopy surface.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1993 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Parametric Study of Parachute Pressure Distribution by Wind Tunnel Testing written by William B. Pepper and published by . This book was released on 1975 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pressure distribution data for solid and ribbon parachutes are presented. Three-foot diameter model parachutes of 0, 10, 15, 20, 25, 30, and 40 percent geometric porosity were tested. Suspension line lengths of 1.0, 1.5, and 2.0 constructed diameters were used. Reefing line lengths of 19, 38, and 57-in. were tested. Two 7 x 10-ft, wind tunnels were used to test over a range of dynamic pressure from 35 to 600 lb/ft2. Integration of the measured pressures over the inflated canopy profiles generally resulted in drag force values which agree within 10 percent of force balance drag data.
