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The latest gas turbine development being undertaken by the Royal Navy is the ACL technology demonstrator programme. The aim of the project is to design and demonstrate a GTA of around 2MW that will have reduced whole life costs when compared to a conventional diesel generator. The project is being managed for the MoD by the Marine Propulsion Systems IPT and being procured through the prime contractor - Turbomeca. The prime contract was awarded in December 2000 and is scheduled to run for five years. This paper describes the main aims and objectives of the project. The paper also gives a detailed overview of the GTA system, describes the key technologies and discusses the outline development programme.

This paper provides a high level overview of why the Royal Navy is seeking to procure a 1–2MW Gas Turbine Alternator as part of a full electric propulsion system. It describes the Royal Navy requirements of marine gas turbines and highlights the reasons for the adoption of Integrated Full Electric Propulsion. The paper also describes the major technical and commercial requirements of the 1–2MW gas turbine alternator and the procurement process that was used to select the prime contractor.Copyright © 2000 by ASME

This paper describes the design concepts and object-oriented architecture of Onyx, an extensible domain framework for computational simulation of gas turbine engines. Onyx provides a flexible environment for defining, modifying and simulating the component-based gas turbine models described in Part 1 of this paper. Using advanced object-oriented technologies such as design patterns and frameworks, Onyx enables users to customize and extend the framework to add new functionality or adapt simulation behavior as required. A customizable visual interface provides high-level symbolic control of propulsion system construction and execution. For computationally-intensive analysis, components may be distributed across heterogeneous computing architectures and operating systems. A distributed gas turbine engine model is developed and simulated to illustrate the use of the framework.Copyright © 1999 by ASME

Two primary topics are addressed in this paper: 1. A brief record of the evolution of U. S. Navy (USN) gas turbine qualification and testing requirements that helped produce the successful engines now in service and 2. Examination of these requirements in light of current and projected defense budgets resulting from changes in the world over the past twenty-five years. The paper proposes changes in the current methods the USN employs in qualifying its gas turbines for surface ship applications. The proposed alternate methods consider commercial testing and service experience as well as testing based on MIL-E-17341 requirements. Finally, the marine gas turbine community is invited to begin a dialogue on the feasibility of these alternate methods.

The paper highlights on-going studies and design efforts by a team of several specialists in aspects related to a type of power generation installation, which consists of a directly coupled closed-cycle gas turbines (the Light Water Reactors have a double loupe energy transfer system coupled by a heat exchanger) to an inherently safe nuclear heat source. In particular the NEREUS installation will be discussed. NEREUS is the God for shipping in Greek mythology, but in this case it stands for: a Naturally safe, Efficient, Reactor, Easy to operate, Ultimately simple and Small. This describes very well the aims of the design team. This part will explain the inherently safe character of the nuclear heat source, the way the energy production in the heat source is controlled, the type of nuclear fuel and the treatment of the nuclear waste, the refuelling, the weight, the dimensions and the construction of the nuclear part of the NEREUS installation. Part two will describe the non-nuclear part of the installation, the possible applications, its potential markets and the technical and financial indications from the on-going study. This paper should be read in conjunction with the paper “The NEREUS installation — the Non-Nuclear part (GT)”.

Development of the Northrop Grumman / Rolls-Royce WR21 Intercooled Recuperated (ICR) Gas Turbine, begun in 1992, is now well advanced and system testing has been completed on eight engine builds at the Royal Navy’s Admiralty Test House located at the Defence Evaluation and Research Agency, Pyestock in the United Kingdom. Test activity is shortly to move to the US Navy’s Test Site at the Naval Surface Warfare Center, Carderock Division – Ship Systems Engineering Station in Philadelphia, PA, where a new test facility has been built to carry out some final development testing and an endurance test. A previous paper on this subject (94-GT-186) defined a test program leading to a design review and the beginning of Qualification Testing. The development program has since evolved and it is the aim of this paper to summarize engine testing to date and set out the plan for conclusion of development testing. The paper will describe the development of the Philadelphia Test Site, as a combined site for the US Navy’s Integrated Power System (IPS) and ICR testing. This will include a description of the advanced, high-accuracy Data Acquisition System (DAS). Finally, the test program and the development and endurance test objectives will be outlined.

The Machinery and Engine Technology (MET) Program of the National Research Council of Canada (NRCC) has established a program for the evaluation of sensors to measure gas turbine engine performance accurately. The precise measurement of fuel flow is an essential part of steady-state gas turbine performance assessment. Prompted by an international engine testing and information exchange program, and a mandate to improve all aspects of gas turbine performance evaluation, the MET Laboratory has critically examined two types of fuel flowmeters, Coriolis and turbine. The two flowmeter types are different in that the Coriolis flowmeter measures mass flow directly, while the turbine flowmeter measures volumetric flow, which must be converted to mass flow for conventional performance analysis. The direct measurement of mass flow, using a Coriolis flowmeter, has many advantages in field testing of gas turbines, because it reduces the risk of errors resulting from the conversion process. Turbine flowmeters, on the other hand, have been regarded as an industry standard because they are compact, rugged, reliable, and relatively inexpensive. This paper describes the project objectives, the experimental installation, and the results of the comparison of the Coriolis and turbine type flowmeters in steady-state performance testing. Discussed are variations between the two types of flowmeters due to fuel characteristics, fuel handling equipment, acoustic and vibration interference and installation effects. Also included in this paper are estimations of measurement uncertainties for both types of flowmeters. Results indicate that the agreement between Coriolis and turbine type flowmeters is good over the entire steady-state operating range of a typical gas turbine engine. In some cases the repeatability of the Coriolis flowmeter is better than the manufacturers specification. Even a significant variation in fuel density (10%), and viscosity (300%), did not appear to compromise the ability of the Coriolis flowmeter to match the performance of the turbine flowmeter. Copyright © 1993 by ASME., ASME 1993 International Gas Turbine and Aeroengine Congress and Exposition, GT 1993, 24 May 1993 through 27 May 1993

The paper describes a general program which has been developed for the prediction of the transient performance of gas turbines. The program is based on the method of continuity of mass flow. It has been applied successfully to a wide range of aero gas turbines, ranging from single to three-spool and from simple jet to bypass types with or without mixed exhausts. The results for three of these engine types are illustrated. Computing times are reasonable, increasing with the complexity of the engine. A parallel paper describes the inclusion of thermal effects in the prediction program.

This paper aims to discuss the factors which led to the selection of the Spey as a marine gas turbine, and the market forces which have made an uprating of the simple cycle unit necessary, and which are now leading to the conception of an advanced cycle version of the gas turbine at even higher power and efficiency. The operational characteristics of warships using these Spey units are compared with those of ships using other propulsion systems. While this paper stands on its own, it can also be regarded as the first part of a series of two; the second part, to be published in Beijing during the September 1985 ASME Gas Turbine Exposition, will deal with that further possible uprating of the Spey to about 22 MW using intercooling and heat exchange to improve its thermal efficiency to about 43%.Copyright © 1985 by ASME

Real-time simulation of gas turbine engine performance is used in a variety of aerospace applications. For simulation of propulsion system performance in flight-simulators, fidelity requirements become increasingly stringent. Significant improvements in simulation fidelity can be obtained when using thermodynamic models instead of the customary (piece-wise) linear real-time models. However, real-time thermodynamic models require sophisticated methods to efficiently solve the model equations on a real-time basis with sufficient speed. NLR has developed the ‘Turbine Engine Real-Time Simulator’ (TERTS) generic real-time engine simulation environment for full thermodynamic simulation of various gas turbine engine configurations. At NLR’s National Simulator Facility (NSF), research is performed on pilot-in-the-loop simulation of complex aircraft and helicopter configurations such as thrust-vectoring and Integrated Flight Propulsion Control (IFPC) concepts. For this application, high-fidelity real-time gas turbine models are required. TERTS has an efficient method for solving the engine model equations real-time. The system is implemented in Matlab-Simulink®, which offers advantages in terms of control system modeling flexibility. With TERTS, detailed thermodynamic real-time engine models can easily be implemented in NSF providing an excellent means to analyze a variety of engine effects on pilot-in-the-loop aircraft performance. In this paper the TERTS modeling environment will be described including the numerical solutions used to comply with the real-time requirements. A TERTS model of a military afterburning turbofan will be presented including simulation results.

Today’s marine gas turbines are started using pneumatic or hydraulic systems. The weight, space, and reliability drawbacks of these systems is well known to ship systems designers who increasingly look to new technology for better solutions. It is not surprising then that the push towards an all-electric ship platform would eventually prompt the development of a suitable electric motor to replace fluid based systems. Lately, research efforts sponsored by the U.S. Navy have intensified to do exactly that. This paper will discuss the background and current efforts to introduce an electric start system for future marine gas turbines.Copyright © 2001 by ASME

The Intercooled Recuperated Gas Turbine Engine System (ICR) is being developed by the United States Navy (USN) for shipboard application as a prime mover. The major development goal of the program is reduced fuel consumption relative to the LM2500, the current fielded gas turbine prime mover. This paper describes a 500-hour endurance test of the ICR system. The test was conducted at Naval Surface Warfare Center Carderock Division (NSWCCD), Philadelphia, in accordance with USN requirements which mimicked the qualification requirements for the system. Data to assess the capability of the ICR to pass the qualification test was collected. Overall, the ICR has demonstrated a readiness to commence qualification testing. The ICR completed the test with a total accumulated operating time of 457 hours and total endurance time of 322 hours. Achievement of the planned 500 endurance hours was precluded by persistent facility waterbrake problems.

Over the years, the word stealth has been used more and more when discussing design and operational characteristics in military applications. New and more challenging techniques are constantly being applied to minimize signatures and thus hinder or delay detection and identification. The Visby Class Corvette is a multipurpose combat ship with 600 tons displacement. The hull is a sandwich construction of a PVC core with carbon fiber/vinyl laminate. The propulsion system consists of two identical CODOG machinery systems, each driving a KaMeWa 125 size Water Jet Unit. The Ship has special requirements for all signatures, i.e. Radar-, Hydro acoustics-, IR- and Magnetic Signature. The High Speed Machinery is twin Honeywell TF50A Gas Turbines, cantilever mounted side by side on the Main Reduction Gearbox housing. The Main Reduction Gearbox is a dual input high performance marine Gearbox designated MA - 107 SBS, designed and manufactured by Cincinnati Gear Co. The Low Speed Machinery is a MTU 16 V 2000 TE90 Diesel Engine connected to the MRG by a power take in shaft. Combustion Air for the Gas Turbines is ducted from the shipside Air Inlet Screen (radar screen) via 3-stage separating filters. The Exhausts from the twin Gas Turbines are combined into one Exhaust Pipe and ducted to the ship transom above the Water Jet stream. Very little can be changed in the Gas Turbine, but high quality such as well balanced rotating part contributes to reduce the signatures. However, the main work has to be accomplished by the building shipyard in cooperation with the Gas Turbine manufacturer. The Main Reduction Gearbox is more available for changes to reduce signatures, but even for the Gearbox the building shipyard has to take design and installation measures. The HSM installation consist mainly of the Gas Turbine Engine, the Main Reduction Gear, Water Jets Unit and surrounding equipment such as main shaft, bearings and so on. The emphasis in this paper is on the GT, MRG and their effect on some of the more well known signatures i.e. RCS, IR, Hydro acoustics and Magnetic. Also some design measures are discussed.

The US Navy along with Textron Marine & Land Systems (TM&LS) is qualifying and field testing the ETF40B gas turbine engine along with Full Authority Digital Engine Control (FADEC) system as possible upgrades to the current TF40B engine and analog control system currently installed on the Landing Craft Air Cushion (LCAC). The ETF40B engine and FADEC control system are of interest due to: increased power, proposed increase in Mean Time Between Overhauls (MTBO), and proposed increase in engine reliability. The primary topics presented in this paper are: 1. The design, development, and qualification of the ETF40B engine and FADEC control system 2. Integration of the ETF40B engine and FADEC into the LCAC 3. Field test data from two LCACs, follow-up testing and implementation

The United States Navy uses the General Electric LM2500 gas turbine engine for main propulsion on its newest surface combatants including the OLIVER HAZARD PERRY (FFG 7) class frigates, SPRUANCE (DD 963) class destroyers, TICONDEROGA (CG 47) class cruisers, ARLIEGH BURKE (DDG 51) class destroyers and SUPPLY (AOE 6) class oilers. Currently, the Navy operates a fleet of over 400 LM2500 gas turbine engines. This paper discusses the ongoing efforts to characterize the availability of the engines aboard ship and pinpoint systems/components that have significant impact on engine reliability. In addition, the program plan to upgrade the LM2500’s standard configuration to improve reliability is delineated.

Gas turbine packagers and end users find themselves today faced with the problem of identifying optimal gas turbine enclosure fire-fighting systems in an era of evolving technology. Research over the last several years has identified water mist as one of the most promising candidates for marine gas turbine enclosures. This paper will discuss the background and implementation of such a system in a military marine gas turbine enclosure.Copyright © 2000 by ASME

U.S. Navy and Rolls -Royce Allison have conducted a fleet evaluation of the Redundant Independent Mechanical Start System (RIMSS) and Full Authority Digital Control (FADC) installed aboard USS Porter (DDG 78), No. 2 Ship Service Gas Turbine Generator (SSGTG). The fleet evaluation has resulted in design, production and operational improvements, which would not have been quickly realized under normal implementation programs. A critical objective of the fleet evaluation demonstrated the system configuration and operational compatibility with existing shipboard environments over the course of a one-year period. This process evaluated the usability of the RIMSS and FADC interface by ships force and the performance of functions related to operation and troubleshooting. It also provided feedback from Navy users for improvements. This paper describes RIMSS and FADC fleet evaluation elements and the benefits derived from performing a fleet evaluation. Fleet evaluation findings aboard USS Porter have resulted in system improvements that were achieved prior to production. Cost savings to the U.S. Navy and the original equipment manufacturer will be realized through out the life cycle of the ships.Copyright © 2000 by ASME

The LM2500 gas turbine has been used on Italian Navy (ITN) ships for more than twenty years. The first engines were installed onboard the “Lupo” class Frigates during the second half of the 1970’s. These gas turbines are operated by means of a Hydro-Mechanical Fuel Control (HMFC) system and started by a pneumatic starter. However, it is known that in some of the latest applications of the LM2500 gas turbines, (e.g. direct drive and water jet systems - Military Sealift Command LMSR cargo vessels and Tirrenia Ferries), electronic fuel control systems and hydraulic starters are used to improve the control and maintenance of the engine, and to reduce the number of air bottles and compressors that have to be installed. The ITN is now evaluating the convenience of using the electronic fuel control systems and hydraulic starters in future surface combatant applications (cruisers, destroyers & frigates) of FIAT GE LM2500 gas turbines. This paper describes the comparison between the different systems that have been carried out by the ITN in the following fields: operations, maintenance and cost effectiveness.

The Rolls-Royce Allison (RRA) 501-K34 serves as the prime mover for the Ship Service Gas Turbine Generator sets (SSGTGs) of the U.S. Navy’s DDG-51 Class ships. Navy experience with the 501-K34 began in 1988 with the testing of the first prototype. Experience to date includes over 700,000 fired hours on a growing fleet of engines. This paper explores that operating experience and discusses future plans to improve the engine’s operational availability while lowering life cycle costs.Copyright © 2000 by ASME

The history of Sir Frank Whittle’s invention of the jet engine is well known. Somewhat less well known is that the Royal Aircraft Establishment embarked in 1926 on developing the gas turbine as a way of driving a propeller. In 1938, A.R.Howell joined the team as a new graduate, and by 1944 he had played a major role in evolving successful axial compressor design methods, which were used in the first two generations of UK gas turbine engines. He was appointed Head of Aerodynamics Department in the National Gas Turbine Establishment when it was created in 1946, and led that team for twenty years. For many years he was a key figure in compressor design in the UK. He returned to personal research before retiring in 1980, and he died in 1988. This paper summarises his personal research contributions and some of the pioneering research he led in NGTE.Copyright © 2000 by ASME

The Integrated High Performance Turbine Engine Technology (IHPTET) is a joint Air Force, Navy, Army, DARPA, NASA, and industry initiative focused on developing higher performance turbine engines. The goal of IHPTET is to develop and demonstrate propulsion systems that would, by the turn of the century, double propulsion capability (1987 base year). For this reason, IHPTET engines are now test beds for a high number of advanced composites, intermetallics and single crystal alloys. While satisfying the performance requirements, the program has another salient objective of cost reduction. This paper will discuss an approach for cost estimating and modeling of components and sub-components, and demonstrate the benefits of employing simulations. Traditional approaches have relied on comparative techniques utilizing complexity factors or Cost Estimating Relationships (CER’s). For advanced materials, these approaches are inadequate, primarily due to non-existence of historic data. A further weakness is their inability to identify cost drivers and quantify cost avoidance potential. Process-oriented cost estimating, albeit cumbersome during build-up and requiring detailed knowledge of manufacturing and process technology, provides a stable foundation for development of a comprehensive cost modeling system. Manufacturing Process Flow Simulation (MPFS) aids in evaluating evolving manufacturing processes (in infancy), studying the impact of alternate manufacturing processes and conducting what-if studies. MPFS can then be incorporated selectively into a cost modeling architecture capable of evaluating production cost for sub-components, components, and complete engines.

Japanese Ministry of International Trade and Industry has been promoting a 300 kW Ceramic Gas Turbine (CGT) research and development program for 10 years. It was begun in 1988 as a part of the “New Sunshine Project”. The development target is to achieve thermal efficiency of over 42% at a turbine inlet temperature (TIT) of 1350°C. We have been taking a part in this project and developing a regenerative two-shaft CGT302. This project will be finished at the end of FY1998. In 1998, we confirmed 31.7 ppm NOx emission at 1350°C by engine test. This result cleared the target emission level of 70 ppm. We also achieved 40.5% of thermal efficiency at 1412°C TIT and we are working to achieve the final target and cumulating operating hours to confirm reliability of ceramic components at 1200°C TIT which is considered to be reasonable temperature for commercial use. This paper describes about ten years development summary of the CGT302.

The use of digital controls in marine gas turbine propulsion has not been as widespread as in other applications. Although these controls have been used in marine applications such as gas turbine electric and water jet drive systems, digital controls have not been applied to a gas turbine direct drive application. This paper describes the use of digital control technology in a marine direct drive application.Copyright © 1999 by ASME

The Ship Service Gas Turbine Generator sets (SSGTGs) on the U.S. Navy’s DDG-51 Class ships have experienced several gas turbine engine failures resulting from seawater contamination of the lube oil. The seawater enters the turbine lube oil system after a corrosion related failure of the lube oil cooler. This paper examines the system design, failure mechanism, and consequence of the failure. It also discusses maintenance actions intended to minimize the possibility of cooler failures, methods that have been used to clean up contaminated systems and alternate cooler designs that are being considered for backfit.Copyright © 1999 by ASME

The CGT301 ceramic gas turbine has been developed under a contract from NEDO as a part of the New Sunshine Program of MITI since 1988 to 1998. The CGT301 is a recuperated, single-shaft ceramic gas turbine. Ceramic parts are used in the hot section of the engine, such as turbine blades, nozzle vanes, combustion liners and so on. As a primary feature of this turbine, the rotors are composed of ceramic blades inserted into metallic disks (“hybrid rotor”) for the future applicability to the large gas turbine. The R & D program consists of three phases, the model metal gas turbine, the primary type ceramic gas turbine and the pilot ceramic gas turbine. The pilot ceramic gas turbine showed etable operation at TIT of 1,350°C. This paper presents the progress in the development of the pilot ceramic gas turbine of CGT301.

The maritime engine test facility at the Defence Evaluation and Research Agency (DERA) Pyestock in the United Kingdom has been involved with the testing of gas turbine engines for the Royal Navy since 1952. This testing has been aimed at proving that the already developed gas turbine can operate in the maritime environment, perform the expected duty cycles, and reach the required levels of availability, reliability, and maintainability as required. To this end, the vast amount of testing at DERA has been the endurance style where the engine is run over extended periods in arduous conditions to test the life of components and with only a minimum amount of data collection. This dramatically changed in 1994 with the beginning of the WR21 Intercooled Recuperated gas turbine (WR21 ICR) development program. The paper describes the benefits of the WR21 ICR over a simple cycle gas turbine, the methodology behind the current development testing, and the evolution of the DERA Pyestock facility. In particular facility designs, instrumentation, data handling, and testing operations to meet the growing needs of the customer to develop this complex cycle gas turbine.

Designing and developing new aerospace propulsion systems is time-consuming and expensive. Computational simulation is a promising means for alleviating this cost, but requires a flexible software simulation system capable of integrating advanced multidisciplinary and multifidelity analysis methods, dynamically constructing arbitrary simulation models, and distributing computationally complex tasks. To address these issues, we have developed Onyx, a Java-based object-oriented domain framework for aerospace propulsion system simulation. This paper presents the design of a common engineering model formalism for use in Onyx. This approach, which is based on hierarchical decomposition and standardized interfaces, provides a flexible component-based representation for gas turbine systems, subsystems and components. It allows new models to be composed programmatically or visually to form more complex models. Onyx’s common engineering model also supports integration of a hierarchy of models which represent the system at differing levels of abstraction. Selection of a particular model is based on a number of criteria, including the level of detail needed, the objective of the simulation, the available knowledge, and given resources. The common engineering model approach is demonstrated by developing gas turbine component models which will be used to compose a gas turbine engine model in Part II of this paper.Copyright © 1999 by ASME

Since 1992, advanced development of an intercooled recuperated (ICR) gas turbine engine for naval ship propulsion has been progressing under a U.S. Navy contract. This paper summarizes progress on the ICR engine development. An overview of the program plan is presented including discussion of significant changes made since contract award. The engine development status is discussed including the significant accomplishments, the recovery from an initial recuperator failure, and the remaining development work.Copyright © 1997 by ASME

The U.S. Navy has long been searching for ways to remove the piping, valves and machinery associated with High Pressure air systems on its ships. This paper discusses alternative methods of starting Ship Service Gas Turbine Generators in order to eliminate these engines as users of HP air.Copyright © 1997 by ASME

The Allison Model AG9130 Ship Service Gas Turbine Generator Set was designed to meet specifications for the DDG 51 Class destroyer of the U.S. Navy. The specifications called for a “turnkey” unit which required only fluid and electrical interfaces with the ship to operate. The fitting of all of the controls, voltage regulating and ancillary equipment on to a single foundation resulted in a cluttered and difficult to maintain set. This paper discusses the program initiated by the Navy to improve the maintainability of the AG9130. It details the changes which have already been made and those currently proposed. It also provides some insight into possible future modifications.Copyright © 1997 by ASME

The WR21 Intercooled Recuperated (ICR) Gas Turbine Engine is being developed as the prime power plant for future US and Foreign Navy ship applications. The development test program started in July 1994 and is still ongoing. One of the many challenges of the ICR design is the development of the compressors and intercooler (IC) wash system. The integration of the IC between the intermediate pressure compressor (IPC) and high pressure compressor (HPC) is unique to current US Navy applications and has introduced new design considerations from traditional wash development programs that must be addressed. Significant increase in wetted surface area of the heat exchanger (HX) matrix and the radial flow are two design aspects unique to the WR21. This paper reviews the design of the WR21 engine and the challenges it offers to developing both crank and on-line compressor/IC wash systems. The baseline design of the water wash systems are discussed, in addition to the water wash test program and its integration into the overall WR2I development program. Details are also given of the off-engine wash delivery system and salt injection systems in place at the test site. Crank wash test results to date are also presented.

The modern low emissions gas turbines operate under some of the most challenging operating conditions as more demands are exercised on their performance. For example, the future engines will have higher thrust-to-weight ratio, improved fuel efficiencies, and high overall pressure ratios. Furthermore, the environmental safety needs will dictate many of the future low emissions combustor designs to be either Lean-Premixed (LP), Lean Direct Injection (LDi), Rich-burn-Quick quench-Lean burn (RQL) or catalytic. These will impose additional demands on developing unique high temperature materials that can survive in oxidizing and reducing environments, under high temperature and pressure conditions, and have other material properties such as superior strength and stiffness. In this paper, first we discuss the salient features of advanced low-emissions gas turbines and their needs for unique material technology development. Next, we discuss the state-of-the-art material technology development as it is applied to current gas turbines. And, finally we review the material developments that will be needed for the future gas turbine engines.Copyright © 1997 by ASME

WR-21 is the designation for the Intercooled, Recuperated (ICR) Gas Turbine Engine System currently under development for the U.S. Navy (USN), with the Royal Navy (RN) and French Navy as major participants. The purpose of the program is to design, develop and qualify a fuel efficient engine system for surface ships. A key enabling technology for the ICR Engine System is the recuperator used to recover exhaust gas heat for reinsertion into the engine cycle thereby reducing specific fuel consumption. A test of a full scale, reduced capacity WR-21 recuperator core was conducted at the Naval Surface Warfare Center, Carderock Division, Ship Systems Engineering Station (NSWCCD-SSES) to determine system response to transient maneuvers typical to ship gas turbine engines. Existing Navy gas turbines located at the site were used to provide the air and gas media for the test apparatus. The test program was directed by Northrop Grumman Marine Systems, the ICR prime contractor, and Allied Signal Aerospace, the recuperator manufacturer. This paper provides a description of the core test premise, test facility, test instrumentation, test experiments and resultant test data.

Based on a ship driven by two controllable pitch propellers (CPP), one single CPP driven by one single gas turbine (GT), a mathematical model for a propulsion system is deduced, and its state-space model is established. In this paper, it is verified that the use of Phase-Linearized Discrete Simulation (PLDS) to estimate large perturbations is practicable. Especially for multivariate systems, this method appears to be rather convenient. We also present the results of simulation to the dynamic braking process of gas turbine propulsion system for a ship at the combined speed/power governing mode and the power governing mode of gas turbine.

The decade of the ’80s was ushered in with a new dimension for designers, the availability of, and the meteoric cost increases of key materials. Though cost consciousness has always been a materials selection factor, current rates of increase make selection decisions more critical. Shortages of key metals such as cobalt, titanium, tantalum, molybdenum, and columbium, as well as potential problems with chromium and aluminum force the designer to carefully weigh his decisions. Questions of basic raw materials availability, metal conversion capacity, and the increasing influence of raw materials cost upon product cost must be considered. Vehicular gas turbine engine designers must evaluate materials selection decisions based upon these factors, and accompanying manufacturing processes to minimize input material requirements., Achieving high performance, with the required durability, at an acceptance cost is a bigger challenge than ever. This paper provides a view of the critical material situation and outlook, and typical options that are available.Copyright © 1981 by ASME

Auxiliary power is often provided on combat vehicles in the U.S. Army for battery charging, operation of auxiliary vehicle equipment when the main engine is not running, or to provide assistance in starting the main engine in extreme cold weather conditions. The use of a gas turbine for these applications is particularly attractive, due to its small size and lightweight. In November 1978, the U.S. Army Tank-Automotive Research and Development Command, Warren, MI awarded a contract to the Turbomach Division of Solar Turbines International, San Diego, CA, for the development of a 10 kW 28 vdc gas turbine powered auxiliary power unit (APU) for installation in the XM1 main battle tank. This paper describes the general features of the Solar Turbomach T-20G-8 Auxiliary Power Unit, a single-shaft gas turbine driven generator set which has been developed under this contract. This APU is one of the family of Gemini powered APUs and is a derivative of the U.S. Army 10 kW gas turbine engine-driven, 60 and 400 Hz generator sets developed by Solar. The electrical components were newly developed for this particular application. Currently, the APU is in qualification testing both in the laboratory and in the XM1 main battle tank.

The Industrial Turbines International GT601 Engine has been designed and is currently being tested as a gas turbine power plant specifically intended for on-highway truck propulsion. The somewhat unique aeromechanical design reflects the uncompromising economic demands of this market in terms of reliability, performance, and cost. This paper describes some of the studies leading to the adoption of the medium-pressure recuperated cycle. The near-term goals of performance superiority relative to current diesels can be achieved with the all-metal version of this engine. The introduction of ceramic components into future high-temperature versions of the GT601 indicates supremacy over projected turbo-compound, adiabatic, bottoming cycle, and similar diesel engine developments projected for the late 1980s.Copyright © 1981 by ASME

From the early days of Navy reciprocating engines through the gas turbine designs of the 1940’s and 50’s, engine test equipment used by the Fleet was relatively simple. As gas turbines developed to higher and higher performance levels, test requirements became more stringent. Engines introduced to the Fleet in the 1970’s required high accuracy test equipment, and therefore, a new trend toward higher precision and digital readout test equipment. Engine test procedures also became increasingly complex due to the complexity of engine designs. During this same time period (early 1970’s) an event was initiated related to gas turbine engine test. NAVAIR began an engine test system standardization effort for Navy IMA’s (Intermediate Maintenance Activities). The NAVAIR standardization effort has resulted in reduced training requirements, reduced maintenance problems, improved logistics support, and sufficient engine test capability to satisfy most complex test requirements. Although the test equipment maintenance and support problems began to dwindle, the operational problems caused by some complex test procedures continued to worsen as qualified Fleet personnel became more scarce. The solution was to develop equipment that could perform the required complex engine test procedure in a fashion that minimized the expertise required by the operator; this solution presented in this paper is PATE (Propulsion Automatic Test Equipment).Copyright © 1981 by ASME

For oil wetted components of gas turbine engines, such as bearings, reduction and accessory drive gears, debris monitoring is the most successful and cost effective condition monitoring technique. However, extensive field service experience demonstrates that full-flow debris monitoring is essential. Full-flow debris monitoring devices, as opposed to chip detectors installed in sumps or lines, monitor the entire scavenge flow. The detection efficiency of properly designed systems can reach 100 percent. This paper briefly discusses models for debris generation in bearings and gears and reviews the principles of successful debris separation and incipient failure detection in gas turbine engines. Several devices are discussed which represent the state-of-the-art in this field, including a centrifugal debris separator for aircraft jet engines which has been shown to be highly effective in field service. Of particular interest to the user of stationary gas turbines is a quantitative debris monitoring system which provides a real-time read out of debris production levels and gives reliable advance warning of impending failure; thus reducing down time, secondary damage and overhaul costs.Copyright © 1981 by ASME

A gas turbine/battery hybrid system adopted as the power plant to propell a passenger car has been in development to seek a better fuel economy to drive. The gas turbine engine is a single-shaft type having 86000 rpm which is coupled directly with a generator to yield electricity. The power is used either to propell wheels and/or to charge battery depending upon the operating conditions of the system. The aim of this study is to attain a better fuel economy by operating the engine only around its rating point regardless to the driving conditions of the vehicle. The experimental vehicle has been studied to evaluate the potential of this unique system. Based on the detailed study of the components of the system and the road-load testings of the vehicle, the potential is seen for the system to be superior than a conventional vehicle. This paper will descrive the experimental results of the vehicle performances by this stage suggesting a good potential of the system when developed fully.

The KTT system is a gas turbine propulsion system designed especially for the automotive application. It’s main features are the three turbines on three different shafts and the close integration of the turbine and transmission into one unit. The first experimental engine, the MkI, based on this system is being developed by United Turbine, a subsidiary to AB Volvo, in Sweden. This paper describes some results of the development of the main components for this engine; the compressor, the turbines and the heat exchanger system. Details on test equipment are given. The results presented are not final and development continues. These results also provide a base for future engine designs.

While the radial in-flow turbine has consistently demonstrated its capability as a high-performance component for small gas turbine engines, its use has been relegated to lower turbine-inlet-temperature cycles due to insurmountable problems with respect to the manufacturing of radial turbine rotors with internal cooling passages. These cycle temperature limitations are not consistent with modern trends toward higher-performance, fuel-conservative engines. This paper presents the results of several Army-sponsored programs, the first of which addresses the performance potential for the high-temperature radial turbine. The subsequent discussion presents the results of two successful programs dedicated to developing fabrication techniques for internally cooled radial turbines, including mechanical integrity testing. Finally, future near-term capabilities are projected.Copyright © 1981 by ASME

San Fernando Laboratories (a division of Dart Industries) has been involved in the development of advanced materials and coating systems for structural use at elevated temperatures. This paper describes these activities including development of additional protection for thermal barrier materials and the development of an extremely high performance SiC coating. Problems of utilizing these and other coatings with carbon-carbon composites are also described.Copyright © 1981 by ASME