Download or read book An Analysis of Parachute Opening Dynamics written by Jarmo Ilmari Uotila and published by . This book was released on 1973 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Parachute Opening Dynamics with Supporting Wind Tunnel Experiements written by Helmut G. Heinrich and published by . This book was released on 1968* with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study is concerned with identification of significant terms in the process of parachute inflation. For finite mass cases, the equations of motion for parachutes inflating in free air and in wind tunnel experiments are established and organized in view of the nonsteady terms of canopy size, systems velocity, included and apparent masses, and the time derivatives of these terms. Wind tunnel experiments are described, the results of which yield graphical and numerical time functions for the significant terms of the equation of motion and the force-time histories. The wind tunnel results are compared with full size test information and certain identities are shown. The significant terms are combined to functions unique for the test conditions and substituted in the equation of motion. Force-time functions so derived compare satisfactorily with measured force histories and the contributions of the individual terms to the instantaneous parachute force can be seen.
Download or read book A Linearised Theory of Parachute Opening Dynamics written by Helmut G. Heinrich and published by . This book was released on 1972 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The inflation of a parachute encompasses problems of aerodynamics, dynamics, and elasticity. The most noticeable effects of the interaction of the events are the opening force and the filling time. Attempts to analyse the opening process and to predict the opening force date back to 1927. Since then a considerable number of methods have been published. Some of them are primarily analytical, others more empirical, and several deal with isolated problems. The earliest and most analytically oriented studies are by Scheubel and O'Hara.
Download or read book Techniques for Selection and Analysis of Parachute Deployment Systems written by Earle K. Huckins and published by . This book was released on 1970 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A New Look at Parachute Opening Dynamics written by Peter R. Payne and published by . This book was released on 1972 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is some evidence to indicate that injuries associated with parachute opening shock are much less frequent than injuries associated with the acceleration loads imposed by ejection seats, even though the stresses presumed to be induced in the human body may often be of the same order. Since all such data is based on operational experience, the details are necessarily vague, and it is hard to draw firm conclusions. The Aeromedical Research Laboratory, USAF, as part of its studies of aircrew injury, decided to see whether there was any difference between the dynamics of parachute opening when used with a rigid anthropometric dummy of the type normally used to obtain opening shock data, and a human parachutist whose body is naturally more resistant.
Download or read book An Analysis of Parachute Opening Forces written by Harry Erwin Ruhsam and published by . This book was released on 1961 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Computational Model that Couples Aerodynamic and Structural Dynamic Behavior of Parachutes During the Opening Process written by Keith R. Stein and published by . This book was released on 1993 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: In parachute research, the canopy inflation process in the least understood and most complex to model. Unfortunately, it is during the opening process that the canopy often experiences the largest deformations and loadings. The complexity of modelling the opening process stems from the coupling between the structural dynamics of the canopy, lines and payload with the aerodynamics of the surrounding fluid medium. The addition of a computational capability to model the coupled opening behavior would greatly assist in the understanding of the canopy inflation process.
Download or read book Pressure Distribution During Parachute Opening written by H. D. Melzig and published by . This book was released on 1966 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation and correlative analysis were conducted to determine the pressure distribution over the surface of parachute canopies during the period of inflation for the infinite mass case and to correlate pressure coefficients with inflating canopy shapes. Parachute canopy models of Circular Flat, 10% Extended Skirt, Ringslot, and Ribbon designs were tested under infinite mass conditions in a 9 x 12 ft low speed wind tunnel. External and internal pressure values were measured at various locations over the surface of the model canopies throughout the period of inflation, and generalized canopy profile shapes were obtined by means of photographic analysis.
Download or read book Notes on a Theoretical Parachute Opening Force Analysis Applied to a General Trajectory written by William P. Ludtke and published by . This book was released on 1988 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report presents a method for calculating the inflation reference time and opening shock forces of the solid-cloth family of parachutes when deployed at an arbitrary trajectory angle to the horizontal. The method is extended to other types of parachutes, but it is limited in that the inflation reference times are not calculated as part of the deployment process. Particular inflation times must be provided as input data to the furnished computer program. The variation of opening shock force versus inflation reference time may be surveyed by providing several values or using actual field test data. Examples are used to demonstrate the effects of canopy cloth rate of airflow, altitude, and trajectory deployment angle for constant velocity and constant dynamic pressure altitude profiles. Keywords: Variable deployment angle, Inflation time, Parachute technology, Opening shock, Calculation methods, Altitude effects.
Download or read book An Analysis of Parachute Opening Shocks written by Charles H. Lowry and published by . This book was released on 1957 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polar Regions of the Earth Geology Tectonics Resource Significance Natural Environment written by and published by . This book was released on with total page 267 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Method for the Calculation of Parachute Opening Forces for High Altitude Balloon Payloads written by Peter L. Miller and published by . This book was released on 1975 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the questions most frequently asked by scientists/experimenters who design balloon payloads concerns the magnitude of the opening forces of the parachute recovery system. Existing theory and an analytical method recently developed for horizontal deployment are adapted to balloon systems requirements. Engineering methods are used to develop expressions which allow the assessment of the parachute opening forces.
Download or read book Analysis of Parachute Deployment of Heavy Cargo written by Helmut G. Heinrich and published by . This book was released on 1963 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: All available experimental values of extraction time, deployment time, opening time, and effective drag coeficient of standard serial delivery systems have been gathered and reduced to comparable conditions. A study has been made to determine the governing parameters in the delivery sequence, and representative values of these parameters have been determined through statistical analysis where possible.
Download or read book Selection of Opening Model for Parachute Scaling Studies written by Eugene E. Niemi and published by . This book was released on 1992 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report consists of a summary of work to program an existing parachute opening dynamics theory for use with research into the scaling laws governing relationships between model and full-scale parachutes during the opening phase. The theory forms a basis to which modifications can be made to predict the opening dynamics of small-scale models. The object is eventually to be able to predict canopy stiffness effects on opening behavior.
Download or read book Postflight Simulation of Parachute Deployment Dynamics of Viking Qualification Flight Tests written by Charles H. Whitlock and published by . This book was released on 1973 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Solutions to the Opening Dynamics of a Parachute written by Bruce R. White and published by . This book was released on 1974 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: In view of existing closed solutions of the parachute opening problem, a numerical solutions technique is presented for generating solutions of the maximum opening force vs deployment velocity of a 28-ft solid flat parachute with a suspended weight of 200 lbs. Also calculated are the filling times of the inflation process. Time-dependent functions of the aerodynamic drag, included air mass of the canopy, apparent mass, inflow velocity function, and a non-linear area-time curve, are used with the momentum and continuity equations at altitudes of 6000, 13,000, and 21,000 ft in the numerical solutions. An idealized canopy shape-time development assumption is made in the calculations. The calculated maximum forces agreed well with experimental test data for some of the empirically selected velocity functions for the 13,000- and 21,000-ft altitude test cases. The maximum calculated forces of the 6000-ft altitude was found to be low in comparison with the experimental field tests. The calculated filling times by use of the continuity equation are generally found to be in excess of the measured filling times from the field tests.
Download or read book Drag and Dynamics of Single and Clustered Parachutes in Freestream and with Wake and Ground Effects written by Helmut G. Heinrich and published by . This book was released on 1966 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of wind tunnel studies concerned with transient and steady state performance of single and clustered parachutes in cargo extraction systems are presented. In Part 1, circular flat and ringslot canopies singly suspended and in clusters of 2, 3, and 4, were deployed in freestream, in the wake of an aircraft, and near a simulated ground. As a further means of analysis, wake pressure surveys were performed on the DHC-4 Caribou and the C-130 Hercules aircraft and are presented in Part 2.
