At present, there is considerable interest in supercritical wing technology for the development of aircraft designed to fly near the speed of sound. The basic principle is the suppression of boundary layer separation by shifting the shock waves that occur on the wing toward the trailing edge and making them as weak as possible. The purpose of this report is to make available to the engineering public mathematical methods for the design of supercritical wings. These methods depend on the numerical solution of the partial differential equations of two-dimensional gas dynamics. The main contribution is a computer program for the design of shockless transonic airfoils using the hodograph transformation and analytic continuation into the complex domain. Another contribution is a program for the analysis of transonic flow with shocks past an airfoil at off-design conditions. In our design work we include a turbulent boundary layer correction. Part I of the paper is devoted to a description of the mathemati cal theory and need not be studied by those primarily concerned with running the programs. Part II is a manual for users of our programs which is independent of the theoretical part. In Part III and in Appendices II and III we give numerical examples and discuss computa tional results. The main substance of the report, however, is contained in the listing of the computer programs themselves in Appendix IV. We have used the Fortran language throughout and we have included numerous comment cards in the listing.
The short period since the publication of Volume 1 of Methods in Membrane Biology has been a time of momentous progress. Calorimetry, electron spin and nuclear magnetic resonance, X-ray diffraction, and freeze-cleavage electron microscopy, reinforced by biochemical analyses and enzymatic studies, have led to universal acceptance of a generalized membrane model. All membrane biologists would agree that a major element of all biological membranes is a bilayer of phospholipids which, in some instances, also contains other lipids, notably sterols and glycolipids. The fatty acid com position of the lipids of most membranes is such that the lipids are above their transition temperatures in their normal environment so that the bilayer is fluid. The microviscosity of the fatty acyl groups decreases pro gressively down the chain so that, at the hydrocarbon interior of the bilayer, the lipid phase has a viscosity approximating that of olive oil at room temperature. As a consequence of this membrane fluidity, a phospholipid molecule is very mobile within the plane of the membrane (moving a distance of about 1-2 fLm in 1 s) but the movement of a phospholipid molecule from one side of the membrane bilayer to the other (flip-flop) is very slow. The lipid bilayer is an essentially inert and rather impermeable struc ture, as shown by many studies with model systems. Proteins, of course, provide the catalytic components of the membranes. as well as playing a significant structural role.
One property common to all cells is transport. Molecules and ions must enter and leave cells by crossing membranes in a controlled manner. The process may take any of several forms: simple diffusion, carrier-mediated diffusion, active transport, or group translocation. There is more than one way to measure each. Transport kinetics, with particular reference to the red blood cell, were discussed in a previous volume. Three chapters deal with the general subject of transport in this volume. Maloney, Kashket, and Wilson summarize the appropriate methodology for studying metabolite and ion transport in bacteria, and Kimmich describes the relevant method ology for the isolated intestinal epithelial cell. The methods described in these two chapters have general application to transport studies in single cells from any source. The approach described in these two complementary articles is extended in the chapter by Hochstadt and her collaborators on the use of isolated membranes from bacterial and mammalian cells for the study of trans port phenomena. If one can prepare a suitable plasma membrane fraction (sealed, impermeable vesicles with the necessary transport components intact), it becomes possible to separate the events of transport from any subsequent metabolism that may occur in the cell. Isolated membrane vesicles are relatively easy to obtain from bacteria, and they are com paratively well studied. Work with similar preparations from cultured mammalian cells is just beginning but has much promise.
The purpose of this book is to survey computational flow research on the design and analysis of supercritical wing sections supported by the National Aeronautics and Space Administration at the Energy Research and Development Administration Mathematics and Computing Laboratory of New York University. The work was performed under NASA Grants NGR 33-016-167 and NGR 33-016-201 and ERDA Contract EY-76-C-02-3077. Computer programs to be listed and described have applications in the study of flight of modern aircraft at high sub sonic speeds. One of the codes generates cascades of shockless tran sonic airfoi~s that are expected to increase significantly the effici ency of compressors and turbines. Good simulation of physically observed flows has been achieved. This work is a sequel to two earlier books [1,2] published by Springer-Verlag under similar titles that we shall refer to as Volumes I and II. New York November 1977 TABLE OF CONTENTS I. INTRODUCTION 1 1. Shockless Airfoils and Supercritical Wing Sections 1 2. Differential Equations of Gas Dynamics 2 II. THE METHOD OF COMPLEX CHARACTERISTICS 5 1. A New Boundary Value Problem 5 2. Topology of the Paths of Integration 8 3. Iterative Scheme for the Map Function 9 III. TRANSONIC AIRFOIL DESIGN CODE 10 1. Isolated Airfoils 10 2. Compressor Cascades 12 3. Turbine Cascades 13 4. Comparison with Experiment 14 IV. TWO-DU1ENSIONAL ANALYSIS CODE 16 1. Wave Drag 16 2. A Fast Solver 19 3. Remarks about Three-Dimensional Flow 24 V. REFERENCES 26 VI.
This handbook is a sequel to an earlier volume entitled "A Theory of Supercritical Wing Sections, with Computer Programs and Examples." Since the completion of the first volume, which we shall refer to as Volume I (cf. [ll), some effort has been made to improve our airfoil design program. A number of more desirable air foils have been designed. In addition several of our wing sections have been tested in wind tunnels. We should like to make this material available here, since it is more convenient to use the design program in conjunction with data for a fairly broad range of examples. Moreover, we have developed new analysis programs that supersede our previous work. Chapter I is devoted to a brief discussion of the mathematics involved in our additions and modifications. There is only a mini mum emphasis on theory, since the representation of important physical phenomena such as boundary layer shock wave interaction and separation is partly empirical. It is our contention, however, that the computer programs provide a better simulation than might have been expected. Chapter II presents numerical results found by our new methods, as well as comparisons with experimental data. Chapter III contains a discussion of the use of the program together with Fortran listings.
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