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One of the most critical gas turbine engine components, the rotor blade tip and casing, is exposed to high thermal load. It becomes a significant design challenge to protect the turbine materials from this severe situation. The purpose of this paper is to study numerically the effect of turbine inlet temperature on the tip leakage flow structure and heat transfer.

In this paper, the effect of turbine inlet temperature on the tip leakage flow structure and heat transfer has been studied numerically. Uniform low (LTIT: 444 K) and high (HTIT: 800 K) turbine inlet temperature, as well as non‐uniform inlet temperature have been considered.

The results showed the higher turbine inlet temperature yields the higher velocity and temperature variations in the leakage flow aerodynamics and heat transfer. For a given turbine geometry and on‐design operating conditions, the turbine power output can be increased by 1.33 times, when the turbine inlet temperature increases 1.80 times. Whereas the averaged heat fluxes on the casing and the blade tip become 2.71 and 2.82 times larger, respectively. Therefore, about 2.8 times larger cooling capacity is required to keep the same turbine material temperature. Furthermore, the maximum heat flux on the blade tip of high turbine inlet temperature case reaches up to 3.348 times larger than that of LTIT case. The effect of the interaction of stator and rotor on heat transfer features is also explored using unsteady simulations. The non‐uniform turbine inlet temperature enhances the heat flux fluctuation on the blade tip and casing.

The increase of turbine inlet temperature is usually proposed to achieve the higher turbine efficiency and the higher turbine power output. However, it has not been reported how much the heat transfer into the blade tip and casing increases with the increased turbine inlet temperature. This paper investigates the heat transfer distributions on the rotor blade tip and casing, associated with the tip leakage flow under high and low turbine inlet temperatures, as well as non‐uniform temperature distribution.

THE Bristol Theseus unit is designed primarily as a power plant suitable for long‐range aircraft. The fundamental features of such power plants are as follows:

Many power generation steam turbine generators today are required in service well beyond their intended lifetimes. Dismantling for inspection is expensive, and owners need to consider all relevant information in making the decision. Application of condition monitoring in all the applicable methods is justified, with each showing different degradation modes. Performance analysis is less well publicised, yet unlike vibration analysis and oil debris analysis, it will show conditions which reduce machine efficiency and output, such as deposits on blades and erosion of internal clearances. Data obtained from tests before and after overhaul also reveal whether any restorative work achieved the expected improvements in performance. The paper outlines, with examples, some condition monitoring techniques that have contributed to retaining some large fossil machines in service for up to 17 years without opening high‐pressure sections.

In an aeroplane, two primary structural sections, the sections having confronting ends with a cavity therebetween, a turbo powerplant supported in the cavity, means hingedly connecting the sections at said ends whereby the sections may be hinged apart to expose the powerplant, and releasable means for holding the sections against such hinging.

TWENTY‐FIVE years ago, the gas turbine was successfully applied to aircraft propulsion for the first time and it was not long after this event that powerful engines of reasonable efficiency appeared. In strong contrast with the early success of large engines, the evolution of equally efficient small engines has proved both difficult and protracted. That few of the major manufacturers have persisted with their development may be surprising but is also indicative of the technical problems involved. Thus it reflects great credit upon Turboméca that they have produced the first turbines to offer a serious challenge to piston engines for small aircraft installations. In this connection, the Astazou occupies a significant position as the first small propeller turbine to achieve any real measure of success, and it has been developed progressively to maintain its early lead over competitors. Consequently this engine was the obvious choice to power the Turbo‐Skyvan.

THE M 45H‐01 is a twin spool turbofan engine being jointly developed by Rolls‐Royce (1971) Limited and SNECMA of France. Its initial application, where it is designated the M 45H Mk 501, is in the VFW Fokker, VFW 614 short haul airliner which started its flight development programme in July 1971 fig 1.

During recent years many outstanding papers have been given on the subject of steam turbine lubrication with particular reference to the development of modern inhibited turbine oils. This series of articles will supplement this work. Particular attention is paid to practical aspects such as descriptions of typical oil systems, their cleaning and maintenance, and also interpretation of laboratory test results.

WITH record attendances during the first days of the Motor Show this year, Exhibitors are asking if it would not be possible to have certain times, or days, reserved for trade buyers. The promoters are obviously concerned with any possible loss of gate money, but it is very true that at times, when stands are crowded with mere sight‐seers it is very difficult for genuine potential buyers and trade personnel to see what they want in the short time that may be at their disposal. These record attendances may not be repeated always; this year is the first time for a long time that anyone can order any car with a reasonable delivery date, and most cars with only a few weeks wait.

In selecting the power plant for the Belfast it was considered imperative that the engine and propeller should each have an appreciable background of experience behind them at the in‐service date and should have extensive development lives ahead of them. Shorts did not relish participating in the teething troubles of new engines and were prepared to make small performance concessions to avoid this possibility. Thus a Stage 2 development of the Rolls‐Royce Tyne engine was chosen in preference to Stage 3 which also met the time scale requirements, and the 4/7000/6 de Havilland propeller of 16 ft. diameter was adopted. Though many civil power plants embody the fruits of military experience with broadly similar engines, the Tyne range springs directly from civil stock. In particular, the service experience which Shorts sought for the Belfast engine has been gained on the T.C.A. Vanguard and the Canadair CL‐44.

In a supersonic aircraft, the combination of a fuse‐lage, and air‐consuming power‐plant in said fuselage, a wing‐structure comprising a wing on cither side of said fuselage each of which wings Has a root joining it to said fuselage, said wings each comprising an upper surface‐member to provide an upper defining surface and a lower surface‐member to provide a lower defining‐surface, said surfaces being joined together at a trailing edge common to both of them, and each of said surface‐members having a forward edge spaced from the other surface‐member over substantially the whole length of the edge, and an air‐passage in each of said wings extending from said forward edges to said power‐plant which air passages are of divergent cross‐section from said forward edges.