Further Aspects of the UK Engine Technology Demonstrator Programme

In 1987, a paper entitled ‘The United Kingdom Engine Technology Demonstrator Programme’ (ASME 87-GT-203) was presented at the Gas Turbine Conference in Anaheim. That paper postulated that a programme of engine technology demonstration ahead of commitment to full-scale development was essential if past problems of cost overrun and inadequate performance at service entry were to be avoided. The paper concluded that the UK had established a balanced programme of technology demonstration, emphasising that Industry and Government must invest this activity with the same commitment traditionally given to projects if the full benefits were to be realised. This follow-up paper presents an expanded view of future programme objectives and how the programme elements formulated for their achievement are to be managed.

1000 Hour Qualification Test of the Textron Lycoming TF40B Marine Gas Turbine Engine for the U.S. Navy LCAC Craft

This paper describes the qualification testing of the TF40B marine gas turbine in accordance with the duty cycle as specified in MIL-E-17341C, but with modifications that reflect the specific engine application to the U.S. Navy LCAC vehicle. Among the particular requirements of the 1000 hour test are continuous operation in a salt-laden environment of given concentration and humidity, and frequent shutdowns from relatively high power with an ensuing soakback interval. The narrative discusses the method of test, the duty cycle, and the results which were obtained. In an epilogue which focuses on posttest activities, a description is given of the corrective actions taken to resolve certain problems that arose during the course of the test. One such problem, namely the occurrence of carbon erosion upon certain hot section components, was eliminated by modification to the combustor, in a very successful posttest test development program.

Organic Fluid Turbines for Various Engine Power Level Turbochargers

Engine exhaust thermal power can be recovered with bottoming Rankine cycle turbine used to drive the engine charging compressor. This paper describes the turbine design concepts and performance analysis of organic fluid turbines for various size turbochargers to be employed with diesel engines of different power levels. Such designs result in monostage full admission turbines with supersonic exit stator nozzles and low degrees of reaction. Turbine expansion efficiencies from 77% to 79% and overall organic fluid turbocharger efficiencies from 53% to 63% are projected with engine power levels ranging from 100 kW to 20 MW. Design problems such as sealing are discussed.

Developing the Rolls-Royce Tay

Description & Application The paper traces the evolution of the Tay engine, launched in response to the requirement for an engine suitable for powering a FAR Part 36 Stage 3 noise compliant aircraft in the 70–100 seat range. The engine, which is derived from the Spey (RB183) MK 555 installed in the Fokker F28 aircraft, incorporates several latest technology features a number of which are already in service in large turbofan engines. Modularity and maintainability are key areas which have been addressed in the design of the engine; these are discussed in regard to operation in service. Results, Conclusions & General Observations The eight engine/two year development programme from first engine run to Type Approval by the United Kingdom Civil Aviation Authority is reviewed with detail description of some of the more important and interesting tests. Certification by the US Federal Aviation Administration was subsequently achieved under reciprocal cross-validation procedures. Flight certification of the two lead aircraft applications is now complete. With completion of type certification of the baseline engine and production deliveries now underway, attention is being turned to growth derivative versions of the engine: an uprated version, due to come on stream late 1988 in an increased weight version of the Fokker 100 has now commenced its certification programme — and further growth capabilities are being explored.

AGT 100 Project Summary

The Allison Gas Turbine Division of General Motors Corporation (GMC) completed the Advanced Gas Turbine Technology Project under contract to the National Aeronautics and Space Administration (NASA) Lewis Research Center (LeRC) using funding received from the Heat Engine Propulsion Division, Office of Transportation Systems in the Conservation and Renewable Energy Group of the Department of Energy (DOE) in the summer of 1987. This advanced, high risk work was initiated in the fall of 1979 under charter from the U. S. Congress to promote an engine for transportation that would provide an alternative to reciprocating spark-ignition (SI) engines for the U. S. automotive industry and simultaneously establish the feasibility of advanced ceramic materials for hot section components to be used in an automotive gas turbine (AGT).

Gas Turbine Training in the Royal Navy

This paper discusses the training given to the personnel of the Marine Engineering Branch of the Royal Navy to enable them to maintain and operate the main propulsion gas turbines fitted in the new generation of warships. Concentrating on the aspects appertaining to gas turbines, the paper describes the training given to both officers and enlisted men during their initial career training both ashore and at sea, and also outlines the training undertaken by personnel to prepare them for appointments to specific ships. Finally, the methods of validating this training to ensure that it meets the requirements of the Fleet are described.

Brushes as High Performance Gas Turbine Seals

Brush seals are the first simple and practical alternative, to the finned labyrinth, for gas turbine air system seals. Their use has been made possible by a combination of innovative design features, combined with advanced materials and manufacturing techniques. Due to the very high rubbing speeds and temperatures, existing in gas turbine air system seal positions, finned labyrinths have been used almost exclusively since the invention of the gas turbine. Development over the years has reduced their leakage flow to the ultimate, but leakage is very much dependent on clearance. A brush seal, replacing the best possible finned labyrinth seal, needing a clearance of 0.7mm, can reduce the flow to approximately 10% of that of the finned seal. The main advantages of brush seals, therefore, are their dramatic improvement in sealing performance. This is combined, however, with their ability to maintain this performance even during and after transient differential movements. These advantages have been developed and demonstrated after many hours rig and engine running. Back to back engine tests, with brush seals, replacing finned labyrinths in key air system seals, have demonstrated a significant improvement in thrust for a given stator outlet temperature (SOT). Flight trials are in progress, on an engine fitted with brush seals, as a further step to their in service use.

Salt Ingestion Test of the AGT 1500 Recuperated Automotive Gas Turbine

A salt ingestion test was performed on the AGT 1500 recuperated automotive gas turbine engine at the Naval Ship Systems Engineering Station (NAVSSES) for the U.S. Marine Corps. The Marine Corps was concerned about the AGT 1500’s ability to tolerate their amphibious and maritime environments. The AGT 1500 was operated for two 450 hour endurance runs burning Navy diesel fuel and ingesting aerosol salt. It suffered no failures or significant loss of power as a result of the ingested salt or operations with Navy diesel fuel.

Thermomechanical Advances for Small Gas Turbine Engines: Present Capabilities and Future Direction in Gas Generator Designs

Performance requirements of tomorrow’s gas turbines demand major improvements in specific fuel consumption and thrust to weight ratio. These stringent requirements, in turn, drive the need for higher operating temperatures and lighter weight engines. Such technical improvements impose severe thermal, structural, and metallurgical demands upon turbine components. A broad spectrum of technology programs is underway at Textron Lycoming to address these challenging requirements. This paper outlines the thermal, structural, and materials research needed for achieving the goals of the small gas turbines of tomorrow.

Technical Approach for a MultiPurpose Small Power Unit

This paper describes the technical approach used to select the engine configuration and performance cycle for a small gas turbine engine. The work was done during the preparation of a proposal to the U.S. Army for an advanced gas-turbine-based MultiPurpose Small Power Unit (MPSPU) in the 50–75 SHP class. Uprating to 100 hp (74.6 kw) with the fewest possible component changes was also desired and will be demonstrated. The proposal was successful, and the resultant engine offering, the T-100 MPSPU, is currently under development. The performance analyses used to quantify the T-100 MPSPU cycle were unique in that component efficiency correlations were used interactively when estimating performance at high levels of work (or pressure ratio per stage) with relatively small size components. The MPSPU program goal is to verify gas turbine technology advancements in small engine components, materials and design techniques that will lead to significant reductions in fuel consumption for this size class engine. Successful incorporation of these technologies will lead to significant savings in fuel usage and logistic requirements.