2.5-MWe Coal-Fired, Atmospheric Fluidized Bed, Recuperated Closed Gas Turbine Electrical Power Generating Plant

The ability of small utilities to meet future customer requirements for fairly priced and reliable electric power will depend on their capability either to purchase inexpensive electric power from larger utilities or to produce power from their own high-efficiency generating systems. In the not too distant future, small utilities will also be faced with the reality of burning coal. In order to help meet these future needs, The Garrett Corporation, in conjunction with the Electric Power Research Institute (EPRI), conducted a conceptual design study to evaluate the suitability of high-efficiency gas turbine engines for external firing with a multifuel (including coal) combustion heat source. A primary goal was to synthesize a system that could be placed on the market by 1985 with normal (but not accelerated) R&D funding.

Future Trends in Subsonic Transport Energy Efficient Turbofan Engines

Details of the NASA sponsored General Electric Energy Efficient Engine (E3) technology program are presented along with a description of the engine, cycle and aircraft system benefits. Opportunities for further performance improvement beyond E3 are examined. Studies leading to the selection of the E3 cycle and configuration are summarized. The advanced technology features, cycle and component performance levels are also presented. An evaluation of the benefits of the fully developed Flight Propulsion System (FPS) is made relative to the NASA program goals by comparing the FPS with the CF6-50C where both are installed in advanced subsonic transport aircraft. Results indicate that a mission fuel saving from 15 to 23 percent is possible depending on mission length.

Gas Turbine Propulsion Systems for Small Naval Ships

Analysis of gas turbine-powered naval ships of 500- to 4000-ton size has been performed for ocean escort and patrol missions with performance levels appropriate to gas turbines of both current and advanced technology. The use of gas turbine systems allows the realization of high mission effectiveness with relatively small ships. For advanced marine gas turbines, the most significant ship benefit would result from increased thermal efficiency of cruise engines by means of regenerative cycles. A secondary improvement, particularly for high dash speeds, would be the reduction of specific weight for dash engines. With such advanced gas turbines, ship sizes may be further reduced for given mission capabilities.

Light Weight Gas Turbine Drivers: Newest Trend in LNG Plant Design

During recent years, the use of gas turbine driven compressors for natural gas liquefaction has been getting increased attention. This paper will describe the application of lightweight Modular Industrial Turbines to conventional liquefaction processes.

The Compound Heat Pump Gas Turbine: An Approach to Energy Conservation for Process Industries

Operating on a combined Brayton and reversed Brayton cycle, this single-shaft engine, utilizing a single compressor for both parts of the cycle, develops simultaneously shaft power, process heat, and refrigeration in prescribed ratios. The engine is described here in terms of a schematic diagram and of analytical performance data covering a range of engine cycle parameters. An illustrative example shows the potential fuel savings obtainable with such an engine in a medium-size meat packing plant.

Digital Control for V/Stol Powerplants

The author describes the evolution of his company’s digital control approach to the Pegasus engine as applied to a single engined VTOL aircraft. The paper describes the digital control system being built by Dowty and Smiths Industries Controls Limited (DSIC). The design is based on extensive engine evaluation of different control configuration with electronic and hydromechanical back-up system. The paper describes the mechanical design, installation on the engine and the cooling of the system including the choice of basic packaging concept. It also discusses the rationale for the particular choice of back-up system and the reliability/safety of flight trade-offs involved.

Experience in Extending the Life of Gas Turbine Blades

This paper presents the effects of deterioration of gas turbine blade life with prolonged service exposure. This deterioration is primarily due to internal microstructural changes and the formation of creep voids or cavitation. Methods of evaluating residual blade life or life trend curves are presented along with a documentation of the creep damage observed. The extension of blade life by Hot isostatic pressing versus reheat treatment is discussed and data is presented to show that complete recovery of properties can be achieved even after the material has suffered extensive internal creep damage. As a result, the time between overhauls for blades can be significantly extended, and the need for replacement blades can be minimized.

A Gas Turbine Maintenance Information System for the Saudi Arabian East-West Crude Oil Pipeline

The 747-mile East-West Crude Oil Pipeline across Saudi Arabia employs 60 gas turbines for pumping and power generation. Mainline pump drives are three United Technologies Corporation FT4A-9 modular industrial gas turbines at each of 11 pumping stations. Two of the three mainline gas turbines are required for maximum throughput, while the third is an operational spare. High reliability and availability constraints and the remote unmanned station concept underscore the need for a modern maintenance information system. This paper describes an independent multiple-fault diagnostic/prognostic system, employing a patented gas path analysis technique.

Effect of Sodium, Potassium, Magnesium, Calcium, and Chlorine on the High Temperature Corrosion of IN-100, U-700, IN-792, and MAR M-509

The effects of potential impurities, such as Na, K, Mg, Ca, and Cl, in coal-derived liquid fuels on accelerated corrosion of IN-100, U-700, IN-792, and Mar M-509 were investigated using a Mach 0.3 burner rig for times to 200 hours in one hour cycles. These impurities were injected in combination as aqueous solutions into the combustor. Other variables were time, temperature, and fuel-to-air ratio. The experimental matrix was a central composite fractional factorial design divided into blocks to allow modification of the design as data was gathered. The extent of corrosion was determined by metal consumption, τ.

Gas Turbine Engine Disk Retirement-for-Cause: An Application of Fracture Mechanics and NDE

Historically, gas turbine engine disks are retired when they accrue an analytically determined lifetime where the first fatigue crack per 1000 disks could be expected. By definition then, 99.9 percent of these components are being retired prematurely. Retirement-for-Cause (RFC) is a procedure, based on Fracture Mechanics, which would allow safe utilization of the full life capacities of each individual disk. Since gas turbine disks are among the most costly of engine components, adopting a RFC philosophy could result in substantial systems life cycle cost savings. These would accrue from reduced replacement costs, conservation of strategic materials such as cobalt, and energy savings.