THE Tsing Hua 15‐ft. wind tunnel, with interchangeable 18‐ft. section for full scale engine and airscrew tests, was recently erected in Central China. It was planned as the…
Abstract
THE Tsing Hua 15‐ft. wind tunnel, with interchangeable 18‐ft. section for full scale engine and airscrew tests, was recently erected in Central China. It was planned as the central organ for aerodynamic research in China and, as such, was subject to interesting design conditions. The main features of the tunnel design, as well as the considerations underlying their choice, are described in this article.
THE 5‐ft. wind‐tunnel of the National Tsing Hua University in Peiping was the first wind‐tunnel to operate in China. The erection of the tunnel was a project of the Aeronautical…
Abstract
THE 5‐ft. wind‐tunnel of the National Tsing Hua University in Peiping was the first wind‐tunnel to operate in China. The erection of the tunnel was a project of the Aeronautical Institute, established in 1933 as a division of the Mechanical Engineering Department. The organisation of the Institute at that time was carried out under the direction of Dr. Y. H. Ku, Dean of Engineering, and Prof. C. T. Chwang, in charge of the Mechanical Engineering Department.
THE Fourth International Congress for Applied Mechanics was held this year at Cambridge from July 3rd to July 9th, under the Presidency of Professor C. E. Inglis, O.B.E., F.R.S…
Abstract
THE Fourth International Congress for Applied Mechanics was held this year at Cambridge from July 3rd to July 9th, under the Presidency of Professor C. E. Inglis, O.B.E., F.R.S. At a conversazione at the Engineering Laboratory, by invitation of Professor Inglis and the staff of the University Engineering Department, members of the Congress were enabled to exhibit their own apparatus. A visit to the Cavendish Laboratory was also arranged for those especially interested in Atomic Physics.
Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory…
Abstract
Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued
THIS paper aims at giving the most important results of modern German research upon the motion of incompressible fluids. Before dealing with the latest developments, I have…
Abstract
THIS paper aims at giving the most important results of modern German research upon the motion of incompressible fluids. Before dealing with the latest developments, I have thought it advisable to give a short account of the older researches upon which the present work is based. It is hoped that this résumé will give a fairly complete survey of the methods that have led to the present insight into the hydrodynamical mechanism.
Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Notes of the United States National…
Abstract
Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Notes of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued
TODAY aviation is a most influential factor in our lives and Brooklyn a most influential factor in aviation. This was clear to all who attended the very successful conference on…
Abstract
TODAY aviation is a most influential factor in our lives and Brooklyn a most influential factor in aviation. This was clear to all who attended the very successful conference on High Speed Aeronautics organized as a feature of the Centennial year by the Department of Aeronautical Engineering and Applied Mechanics of the Institute. Over 600 research workers and technicians assembled at the Engineering Societies Building, New York, to hear and to discuss papers by scientists and engineers from America, England, France, Germany, Italy and Sweden.
J.C. de C. Henderson and W.G. Bickley
A SKELETAL structure is defined as one which can be ideally represented by linear (one‐dimensional) members appropriately connected at point nodes. The members are not necessarily…
Abstract
A SKELETAL structure is defined as one which can be ideally represented by linear (one‐dimensional) members appropriately connected at point nodes. The members are not necessarily straight or in one plane. The term structure will be used to denote a skeletal structure.
The term ‘hypersonic flow’ was first used by Tsien in 1946 to denote a (low for which the main stream Mach number was large compared with unity, and he demonstrated that such…
Abstract
The term ‘hypersonic flow’ was first used by Tsien in 1946 to denote a (low for which the main stream Mach number was large compared with unity, and he demonstrated that such flows displayed characteristic features which justified the use of a special name. Tsien confined his considerations to a perfect gas with constant specific heats but since 1946 interest has widened to the flow of real fluids at high Mach numbers, this interest being mainly stimulated by the problems of the re‐entry at high speeds into the earth's atmosphere of missiles and satellites. An essential feature of hypersonic flow is that relative to the undisturbed flow direction the inclination of the nose shock of a body immersed in the fluid is of the same order of magnitude as the mean inclination of the surface over the forward part of the body, and the region between shock and body, the so‐called ‘shock layer’, is relatively narrow there. Another characteristic feature is the high temperature that developes in this layer in problems of practical interest and the associated effects on the physical and chemical properties of the medium. Thus, not only must account be taken of the variation of the specific heats with temperature for a real fluid but the consequences of dissociation and ionization of the fluid on crossing the nose shock must be considered. The interaction of the boundary layer with the flow external to it and with the nose shock becomes of increasing importance, as well as increasingly complex, with increase of main stream Mach number. Finally, account must be taken of the molecular nature of the medium in problems where the density is sufficiently low for the mean free path of the molecules to be a significant ratio of a typical dimension of the body or of its boundary layer thickness.
THE extensive series of investigations to be discussed in the present paper has its origin in an attempt to clarify the reason for certain discrepancies, which have long plagued…
Abstract
THE extensive series of investigations to be discussed in the present paper has its origin in an attempt to clarify the reason for certain discrepancies, which have long plagued aerodynamicists, between the results of tests on similar aerofoils carried out in different wind tunnels. It has been well known for many years that the Reynolds number has an important influence on aerofoil characteristics. It is therefore highly desirable that aerofoil tests, to be useful for full‐scale predictions, be made at as large a value of the Reynolds number as possible. For several years the variable density wind tunnel of the National Advisory Committee for Aeronautics has been able to employ Reynolds numbers considerably higher than were attainable in any other wind tunnel. Its results have, therefore, very properly been generally accepted as furnishing the standard aerofoil data for aeroplane designers in the United States, and to some extent also in Europe. It appears from the present investigation that another factor, turbulence, may be of the same order of importance as the Reynolds number in determining certain aerofoil characteristics. In discussing the possible effects of this factor, it is desirable that as wide variations in its magnitude as can be obtained should be considered. The turbulence characteristics of the N.A.C.A. variable density tunnel and of the wind tunnel at the Guggenheim Aeronautics Laboratory at the California Institute of Technology (referred to in the figures as Galcit) are as different as those of any two large contemporary wind tunnels. It is for this reason that in the following discussion results obtained in these two tunnels are compared.