Download or read book Some Recent Experimental Studies on the Aeroelastic Stability of Thin Cylindrical Shells Pt i Experimental Study of the Supersonic Flow Field Over an Aeroelastic Ogive written by P. L. Daily and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Some Recent Experimental Studies on the Aeroelastic Stability of Thin Cylindrical Shells Part I an Experimental Study of the Supersonic Flow Field Over an Aeroelastic Ogive Cylinder Model with Boundary Layer Control written by Philip L. Daily and published by . This book was released on 1970 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study was conducted as the first phase in a program to determine the influence of a compressible viscous boundary layer on cylindrical shell panel flutter. In the first part of the experiment, a study was conducted to provide data on the uniformity of the surface pressure distribution over the region of the flutter model where the thin cylindrical shells were mounted for the flutter experiments. The measured data confirmed that for all flow conditions above Mach Number 1.2, no significant pressure gradient existed over the region of the model where the flutter shells were mounted for testing. A study was then conducted to determine the effectiveness of the boundary layer control system for increasing the boundary layer thickness over the region of the model where the flutter shells were mounted. The boundary layer control system proved to be quite effective and under optimum conditions could increase the displacement and momentum thicknesses by a factor of 10. In general, the displacement and momentum thicknesses could be increased by at least 50% for most of the operating conditions of the wind tunnels by maximum activation of the boundary layer control systems. Finally boundary layer transition and profile similarity studies were conducted to determine the range of free stream flow conditions and boundary layer control activation rates where boundary layer profile similarity could be achieved over the test shell area of the model. The results indicate that similar laminar or turbulent boundary layer profiles can be maintained over the test region of the model for flow conditions where panel flutter can be expected to occur. (Author).

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1976 with total page 978 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book OAR Research Review written by United States. Air Force. Office of Aerospace Research and published by . This book was released on 1968 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Study on the Aeroelastic Stability of Thin Cylindrical Shells at the Lower Supersonic Mach Numbers written by Ronald O. Stearman and published by . This book was released on 1966 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the initial phases of the test static pressure and boundary layer profile surveys were made over a rigid instrumented shell mounted in the position normally occupied by the flutter shells. The model boundary layer control system was also checked. In the final test phase the aeroelastic stability of five thin shells was investigated with the shells loaded under an axial compressive force and/or internal pressure. A highly divergent panel flutter instability occurred on all of the models tested, each shell being destroyed within less than a second. High speed motion pictures were taken during the flutter of three of the shells. These pictures revealed that the initial instability appeared either in the form of a local dimple or in the form of a wave traveling in the free stream direction. The characteristic wave lengths of these initial instabilities were small compared to the shell radius and length. A comparison of the present experimental results with some earlier studies conducted at the higher supersonic Mach numbers indicates that the critical ratio of dynamic pressure to bending stiffness required to induce flutter is approximately three times that found at the higher Mach numbers. Considerable disagreement was also observed between these experimental results and the results of two different theoretical analyses. (Author).

Download or read book Research Review written by and published by . This book was released on 1969-11 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Some Recent Experimental Studies on the Aeroelastic Stability on Thin Cylindrical Shells written by Philip L. Daily and published by . This book was released on 1970 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Research Review written by United States. Air Force. Office of Aerospace Research and published by . This book was released on 1969 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aeronautical Engineering written by and published by . This book was released on 1971 with total page 580 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)

Download or read book Some Recent Experimental Studies on the Aeroelastic Stability of Thin Cylindrical Shells written by Philip L. Daily and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aeroelastic Stability Characteristics of Cylindrical Shells Considering Imperfections and Edge Constraint written by Gerald W. Barr and published by . This book was released on 1968 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent wind tunnel results indicate that the existing cylindrical shell aeroelastic stability theories are generally nonconservative. Therefore, some type of destabilizing mechanism is needed in the present theory to enhance correlation with experiment. In the paper, the dynamic stability behavior of thin circular cylindrical shells subjected to a supersonic flow field is investigated theoretically and compared with existing experimental data. Combined effects of axisymmetric initial geometric imperfections, radial edge constraint, and prestability deformations are considered. The cylinder's motion is described with nonlinear Donnell type shell equations coupled with a linear 'piston theory' aerodynamic approximation. A modal type approach employing Galerkin's approximate technique is used to investigate the dynamic stability about the shell's deformed middle surface. Prestability deformations alone have been shown to have very little influence on the aeroelastic stability behavior of very thin shells. However, with the inclusion of initial imperfections, the combined effect is destabilizing. The resulting aeroelastic stability boundaries correlate quite well with existing experimental data. (Author).

Download or read book Recent Contributions to Experiments on Cylindrical Shell Panel Flutter written by W. Horn and published by . This book was released on 1971 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental studies have been carried out on the aeroelastic stability of several cylindrical shell configurations under various internal stress and supersonic flow conditions. These experiments were conducted in the AEDC Propulsion Wind Tunnel Facility over the Mach number range 1.2 to 3.5. Some of the initial experiments demonstrated that the still-air buckling characteristics of thin cylindrical shells were not significantly influenced by the supersonic air stream. The wealth of still air buckling data can consequently be employed to determine the buckling loads of cylindrical shells exposed to a supersonic flow field. (Author).

Download or read book An experimental study of the supersonic flow field over an aeroelastic ogive cylinder model with boundary layer control written by Philip Louis Daily and published by . This book was released on 1969 with total page 133 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 U S Government Research and Development Reports Index written by and published by . This book was released on 1970 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Analytical and Experimental Investigation of the Aeroelastic Stability of Cylindrical Shells at the Subsonic and Supersonic Mach Numbers written by Walter Julian Horn and published by . This book was released on 1972 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Theoretical Investigation on the Aeroelastic Stability of Isotropic Cylindrical Shells at Both the High and Low Supersonic Mach Numbers written by Larry Carter and published by . This book was released on 1966 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study includes an investigation on the aeroelastic stability of thin isotropic cylindrical shells over the Mach number range 1.2 to 3. The analysis coupled the Donnell shell equations with a linear piston theory to approximate the aerodynamic forces at the high supersonic Mach numbers while a slender body theory was used to approximate the aerodynamic forces at the low supersonic Mach numbers. The influence of the shell's structural boundary conditions and initial stresses on its aeroelastic stability was also investigated. This included a study of the shell stability around both its deformed and undeformed state, the deformed state being due to the initial stresses in the shell. The theoretical results were finally compared with recent experimental studies conducted at both the high and low supersonic Mach numbers. (Author).