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This paper aims to present the development of a highly parallel finite-difference computational fluid dynamics code in generalized curvilinear coordinates system. The objectives are to handle internal and external flows in fairly complex geometries including shock waves, compressible turbulence and heat transfer.

The code is equipped with high-order discretization schemes to improve the computational accuracy of the solution algorithm. Besides, a new method to deal with the geometrical singularities, so-called domain decomposition method (DDM), is implemented. The DDM consists of using two different meshes communicating with each other, where the base mesh is Cartesian and the overlapped one a hollow cylinder.

The robustness of the present implemented code is appraised through several numerical test cases including a vortex advection, supersonic compressible flow over a cylinder, Poiseuille flow, turbulent channel and pipe flows. The results obtained here are in an excellent agreement when compared to the experimental data and the previous direct numerical simulation (DNS). As for the DDM strategy, it was successful as simulation time is clearly decreased and the connection between the two subdomains does not create spurious oscillations.

In sum, the developed solver was capable of solving, accurately and with high-precision, two- and three-dimensional compressible flows including fairly complex geometries. It is noted that the data provided by the DNS of supersonic pipe flows are not abundant in the literature and therefore will be available online for the community.

ON Friday, March 24, 1961, the Minister of Aviation, Mr Peter Thorneyeroft, officially opened a new high supersonic speed wind tunnel at the Royal Aircraft Establishment, Bedford. This tunnel provides the final stage in the present plans for expansion of the wind tunnel facilities at Bedford, being capable of providing speeds from Mach 2.5 up to Mach 5 in a working section measuring 4x3 ft. Three other tunnels arc already in operation at Bedford—these being the 13x9 ft. working section low‐speed tunnel, the 3x3 ft. tunnel, which is transonic and supersonic to Mach 2, and the 8x8 ft. tunnel, which is subsonic and supersonic to Mach 2.8.

The paper discusses the types of singular points occurring in the first‐order ordinary differential equation which describes compressible viscous flow in a channel or stream tube of varying cross‐sectional area. The treatment is one‐dimensional, viscosity being allowed for by assuming a tangential stress acting on the circumference. The resulting patterns of the integral curves arc examined. It is shown that for convergent‐divergent channels whose profile has no point of inflexion, the singular point is a saddle point, as is the case in frictionlcss flow. However, the sonic section or the section of highest or lowest Mach number do not coincide with the throat but arc situated downstream of it in the divergent portion. The slopes of the integral curves which pass through the sonic section arc evaluated. When the convergent‐divergent channel has a point of inflexion in its profile there may be two singular points, the first being a saddle point and the second cither a spiral point or a nodal point. It is shown that spiral points are more likely to occur than nodal points and that, when they occur, there is no radical change in the Mach number variation along the channel due to friction. On the other hand, the existence of a nodal point admits the possibility of a continuous transition from supersonic to subsonic How in which the Mach number at exit may vary within certain limits, the Mach number in the second sonic section remaining always equal to unity. In all types of flow there arc portions of the channel over which the influence of friction outweighs that of area change.

A METHOD of joining pipes which does not make use of heavy bulky fittings has always been required in the aircraft industry. In addition, as aircraft speeds increase well into the supersonic range, the need for more reliable joints that will withstand even more rigorous working conditions becomes apparent.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued

TO say that the Twenty‐fourth S.B.A.C. Show was an unqualified success is perhaps to gild the lily. True there were disappointments— the delay which kept the TSR‐2 on the ground until well after the Show being one—but on the whole the British industry was well pleased with Farnborough week and if future sales could be related to the number of visitors then the order books would be full for many years to come. The total attendance at the Show was well over 400,000—this figure including just under 300,000 members of the public who paid to enter on the last three days of the Show. Those who argued in favour of allowing a two‐year interval between the 1962 Show and this one seem to be fully vindicated, for these attendance figures are an all‐time record. This augurs well for the future for it would appear that potential customers from overseas are still anxious to attend the Farnborough Show, while the public attendance figures indicate that Britain is still air‐minded to a very healthy degree. It is difficult to pick out any one feature or even one aircraft as being really outstanding at Farnborough, but certainly the range of rear‐engined civil jets (HS. 125, BAC One‐Eleven, Trident and VCIQ) served as a re‐minder that British aeronautical engineering prowess is without parallel, while the number of rotorcraft to be seen in the flying display empha‐sized the growing importance of the helicopter in both civil and military operations. As far as the value of Farnborough is concerned, it is certainly a most useful shop window for British aerospace products, and if few new orders are actually received at Farnborough, a very large number are announced— as our ’Orders and Contracts' column on page 332 bears witness. It is not possible to cover every exhibit displayed at the Farnborough Show but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

THE earlier classical treatises on aerodynamics concerned themselves with the properties of incompressible fluids. The theory developed on this basis gave an excellent theoretical background to the aeronautical engineer and made possible a scientific approach to the problems of aircraft flight. With the steady increase of aircraft speed, however, it soon became evident that the theory would have to be extended to take compressibility into account. One important result, brought out by Glauert's analysis, was the modification of the flow pattern with increasing Mach number. A more striking divergence of compressible from incompressible flow, first encountered at near sonic speeds, is the occurrence of shock waves. A shock wave, in the specialized aeronautical sense, is a pressure impulse travelling through the flow causing a sudden transition from supersonic to subsonic speeds (normal to the wave front) with an attendant increase in pressure and temperature. A brief statement of this sort, however, is of little or no value in giving an idea of the physical nature of the phenomenon. A considerable amount of attention is now focused on the repercussions of shock waves on aeroplane design. It is far easier to understand these design trends if one has a good grasp of the fundamentals underlying the problem. This article sets out to give a brief survey of these fundamentals. It is not easy also to give a complete physical picture of a shock wave but at least a discussion of their formation, propagation, etc. goes a long way towards clarifying one's ideas.

OPTIMIZATION of wing design aims at finding the best compromise between conflicting aerodynamic requirements and considerations of structure weight and stiffness. Since the profile drag of a laminarizcd aircraft is very small, the induced drag has to be correspondingly reduced for proper matching. Reduction of induced drag can only be obtained, for a given dynamic pressure at the cruise, by increasing the span, and that reflects on structure weight.

THE graphical methods of one‐dimensional gas dynamics are reviewed and developed to obtain a complete representation of adiabatic flow of perfect gases in ducts of constant cross‐section. The dimensionless charts, from which the variation of the state of the gas along the duct axis can be determined, are analysed and the methods of their construction given. The form of the charts depends only on the value of the ratio of specific heats.

THE B.A.C./Sud Concord supersonic airliner which was the subject of an official agreement signed by Mr Julian Amcry, the British Minister of Aviation, and His Excellency M. GcoiTroy dc Courccl, the French Ambassador, on November 29, 1962 , will be powered by four Bristol Siddeley Olympus Mark 593 turbojets. These engines are being developed and manufactured jointly by the Societe Nationale d'Etude et de Construction de Moteurs d'Aviation (S.N.E.C.M.A.) and Bristol Siddeley Engines Ltd. While Bristol Siddeley Engines will be responsible for the actual engines, S.N.E.C.M.A. is developing the reheat system, final nozzle and thrust rcverscr.