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This paper aims to develop a dynamic performance model of three-shaft gas turbine for electricity generation and to study a multi-loop control strategy of three-shaft gas turbine for electricity generation.

In this paper, the dynamic performance model of the three-shaft gas turbine is established and developed. A novel approach, variable partial differential coefficient deviation linearization method is used to simulate the dynamic performance of the three-shaft gas turbine. Single-loop control system, feed-forward feedback control system and cascade system are assessed to control the engine during transient operation.

A novel approach, variable partial differential coefficient deviation linearization method is used to simulate the dynamic performance of the three-shaft gas turbine. According to the results shown, the cascade control system is most satisfactory due to its fastest response and the best stability and robustness.

The method of variable partial linearization is adopted to make the dynamic simulation of the model achieve higher precision, better steady state and less computation time. This paper provides a theoretical study for the multi-loop control system of a marine three-shaft gas turbine.

IT is nearly fifteen years since the introduction into civil operations of the Dart turboprop in the Vickers Viscount and the Ghost turbojet in the dc Havilland Comet. For many years it was thought that the turboprop would remain dominant in the short and medium haul classes, but the continued demand for higher cruising speeds and the passenger appeal of the jet have been largely responsible for the turboprop aircraft being superseded by the new generation of turbofan aircraft.

THE Rolls‐Royce RB.211 turbofan engine in various ratings is on firm offer for the proposed large three‐engined transport aircraft such as the McDonnell Douglas DC‐10 and the Lockheed 1011 now being designed in the United States. First certificated engines will be available in December 1970, at a basic price of around $½ million varying according to the rating chosen. The engine is also offered for 200‐seat twin engine transports. A typical specification is as follows:

With a delivery of 9,000 kW at 59 deg.F./30 in. Hg. and an overall efficiency of 24.5 per cent at full load, a new gas turbine power plant has been developed by Svenska Turbinfabriks AB. Ljungström, of Finspång, Sweden. The three‐shaft design incorporates two axial‐flow compressors in series, two turbines each driving one of these compressors, and a power turbine directly driving the alternator. All components have been placed in a straight line with the combustor located between the high pressure compressor and the high pressure turbine and with the low‐pressure rotor arranged coaxially with the high pressure rotor.

This paper seeks to evaluate the potential of heat exchanged aeroengines for future Unmanned Aerial Vehicle (UAV), helicopter, and aircraft propulsion, with emphasis placed on reduced emissions, lower fuel burn, and less noise.

Aeroengine performance analyses were carried out covering a wide range of parameters for more complex thermodynamic cycles. This led to the identification of major component features and the establishing of preconceptual aeroengine layout concepts for various types of recuperated and ICR variants.

Novel aeroengine architectures were identified for heat exchanged turboshaft, turboprop, and turbofan variants covering a wide range of applications. While conceptual in nature, the results of the analyses and design studies generally concluded that heat exchanged engines represent a viable solution to meet demanding defence and commercial aeropropulsion needs in the 2015‐2020 timeframe, but they would require extensive development.

As highlighted in Parts I and II, early development work was focused on the use of recuperation, but this is only practical with compressor pressure ratios up to about 10. For today's aeroengines with pressure ratios up to about 50, improvement in SFC can only be realised by incorporating intercooling and recuperation. The new aeroengine concepts presented are clearly in an embryonic stage, but these should enable gas turbine and heat exchanger specialists to advance the technology by conducting more in‐depth analytical and design studies to establish higher efficiency and “greener” gas turbine aviation propulsion systems.

It is recognised that meeting future environmental and economic requirements will have a profound effect on aeroengine design and operation, and near‐term efforts will be focused on improving conventional simple‐cycle engines. This paper has addressed the longer‐term potential of heat exchanged aeroengines and has discussed novel design concepts. A deployment strategy, aimed at gaining confidence with emphasis placed on assuring engine reliability, has been suggested, with the initial development and flight worthiness test of a small recuperated turboprop engine for UAVs, followed by a larger recuperated turboshaft engine for a military helicopter, and then advancement to a larger and far more complex ICR turbofan engine.

Rolls‐Royce Ltd. designs, develops and manufactures gas turbine engines for aircraft and marine industrial purposes and in 1971 the gas turbine business was reconstructed to continue independently of the motor car and other piston engine manufacture. The British Government is the sole shareholder, but the Company determines its own commercial policy.

THE aircraft gas turbine is intriguing in that there were early attempts at its development not only by the established aero engine companies and research establishments in many countries, but also by manufacturers of marine and industrial turbines and — most successfully — by individuals. The aero engine companies failed because in virtually every instance they attempted to produce a power unit of comparable or lower specific fuel consumption to the traditional piston engine. This led to unduly complex designs involving unattainably high component efficiencies and turbine temperatures at far too early a stage in the development of the new prime mover.

Accles & Pollock Ltd. of Oldbury, Worcestershire, a TI Steel Tube Division company, will be exhibiting a comprehensive range of precision steel tube and tubular products, including plain, annularly convoluted and thin wall tube, at Farnborough.

THE ROLLS‐ROYCE RB 211 three‐shaft turbofan was certificated by the Air Registration Board and the Federal Aviation Administration in February. This advanced engine, rated at 42,0001b take‐off thrust, is now being delivered in quantity to Lockheed for installation in TriStar airliners, 22 of which are scheduled for delivery in 1972. The first operators of this new RB 211‐powered airliner are Eastern Air Lines and Trans World Airlines.

IT is usually supposed that the designer of a gas turbine engine has considerable freedom in choosing the pressures, temperatures and other features. Indeed this apparent flexibility has been claimed as an inherent advantage of the gas turbine, which enables it to be tailor‐made for any prescribed duty.