bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of Ceramic Components for a Power Generating Gas Turbine
Authors: Hara Y. , Tsuchiya T. , Maeda F. , Tsuji I. , Wada K. 
Published: March 2015

Since 1984, TEPCO (Tokyo Electric Power Co., Inc.) has been conducting a cooperative research program to apply ceramics to power generating gas turbines with three Japanese gas turbine manufacturers (Toshiba Corporation, Mitsubishi Heavy Industries, Ltd., and Hitachi, Ltd.). The goal of the program is development of a 20MW class gas turbine with turbine inlet temperature of 1,300C (1,573K) to improve the efficiency of coal gasification combined cycle power generation.
Preliminary design of the gas turbine was conducted during 1984–1985 and basic design criteria, such as desired configuration and material properties, were established. Based on the results of the preliminary design, it was decided to apply ceramics to the liner and transition piece of the combustor, the 1st and 2nd stage nozzles and 1st stage rotor in a three stage turbine. As for the rotors, development efforts were also applied to thermal barrier coatings on conventional metal blades.
Parallel efforts have been conducted on the development of each ceramic component since 1986. This paper will review the design of ceramic components from structural and material standpoints, and present results obtained from tests conducted under various operational conditions.
Development of T-100 Multipurpose Small Power Unit
Authors: Napier James C. 
Published: March 2015

The T-100 Multipurpose Small Power Unit (MPSPU) is a small gas turbine power unit technology demonstrator. Funding has been provided by the U. S. Army for development and test demonstration of this unit. The T-100 integrates emerging component technologies into a single power unit. The technology is targeted for use in airborne, vehicular, and ground auxiliary power applications. Three power levels will be demonstrated with a family of engines derived from the baseline 50-horsepower (HP) unit and include a modified 75-HP unit and two advanced technology versions of the Uprated 100-HP unit.
The T-100 MPSPU program approach was to develop advanced component concepts with analyses and rig tests to determine total system performance in the MPSPU power units. The results of this process are summarized here. Component rig tests included the inlet protection system, compressor stage, combustor, and turbine stage. These rig tests demonstrated advances in component capabilities for small turbomachinery. Power unit testing has demonstrated achievable levels in specific fuel consumption (SFC) and overall performance for a gas turbine power unit in this class.
Design and Analysis of a High Pitch to Chord Ratio Cascade Representative of Ducted Propfans
Authors: Weber A. , Steinert W. , Starken H. 
Published: March 2015

Efforts to reduce the specific fuel consumption of a modern aero engine focus in particular on increasing the by-pass ratio beyond the current level of around 5. One concept is the counterrotating shrouded propfan operating at low overall pressure ratio and having only very few fan blades of extremely high pitch/chord ratios. The relative inlet Mach numbers cover a range from 0.7 at the hub to 1.1 at the tip section of the first rotor.
A propfan cascade was designed by taking into account two characteristic features of a propfan blade-blade section:
• a very high pitch/chord ratio of s/c = 2.25
• an inlet Mach number of M1 = 0.90 which leads to transonic flow conditions inside the blade passage
In the design process a profile generator and a quasi-3D Euler solver were used iteratively to optimize the profile Mach number distribution. Boundary layer behavior was checked with an integral boundary layer code. The cascade design was verified experimentally in the transonic cascade wind tunnel of DLR at Cologne. The extensive experimental results confirm the design goal of roughly 5 degree flow turning. A total pressure loss coefficient of less than 1.5% was measured at design conditions. This validates the very high efficiency level the propfan concept is calling for.
A 2D Navier-Stokes flow analysis code yields good results in comparison to the experimental ones.
Gas Turbines Installations for EDF’s Island Grids
Authors: Cazemajou C. , Morzelle C. 
Published: March 2015

EDF is responsible for the production and distribution of electricity on the French islands in Europe and overseas, such as:
- Corsica (in the Mediterranean),
- Martinique (in the Caribbean),
- Guadeloupe (in the Caribbean),
- Reunion (in the Indian Ocean),
- and French Guiana in South America.
Technical and economic studies revealed the viability in these regions of single cycle gas turbine technology for supplying peak demand requirements, or providing transitory means of production pending the installation of heavier production units (conventional thermal power plants, diesel generators or hydropower).
After consultations with the major European manufacturers, a list of machines with the capacity to meet the generation specifications, and their characteristics, was prepared.
On mainland France EDF had equipped its production units with 24 MW Alsthom MS 5000 and MS 5001 gas turbines. These were little used and studies showed the economic viability of transferring these units to island regions.
The program finally adopted was to install the following power generation facilities:
JARRY SUD (GUADELOUPE): 2 ALSTHOM MS 5001 – 20 MW – 40 MW
KOUROU (FRENCH GUIANA): 2 COOPER ROLLS – 13 MW – 26 MW; 1 ROLLS ROYCE – 11 MW – 11 MW
LUCCIANA (CORSICA): 2 ALSTHOM MS 5000 – 24 MW – 48 MW
LE PORT (REUNION): 2 ALSTHOM MS 5001 – 20 MW – 40 MW
POINTE DES CARRIERES (MARTINIQUE): 2 ALSTHOM MS 5001 – 20 MW – 40 MW
or total rated power of: 205 MW
The technical details, costs and scheduling of these works are described in the paper.
Finally, the authors describe the future development prospects for gas turbines in these regions, and especially certain combined cycle projects for Corsica coupled with a proposed Italy-Corsica-Sardinia natural gas link.
Numerical Study of Branched Turboprop Inlet Ducts Using a Multiple Block Grid Procedure
Authors: Tolpadi Anil K. , Braaten Mark E. 
Published: March 2015

An important requirement in the design of an inlet duct of a turboprop engine is the ability to provide foreign object damage protection. A possible method for providing this protection is to include a bypass branch duct as an integral part of the main inlet duct. This arrangement would divert ingested debris away from the engine through the bypass. However, such an arrangement could raise the possibility of separated flow in the inlet, which in turn can increase pressure losses if not properly accounted for during the design.
A fully elliptic three-dimensional body-fitted computational fluid dynamics (CFD) code based on pressure correction techniques has been developed that has the capability of performing multiple block grid calculations compatible with present day turboshaft and turboprop branched inlet ducts. Calculations are iteratively performed between sets of overlapping grids with one grid representing the main duct and a second grid representing the branch duct. Both the grid generator and the flow solver have been suitably developed to achieve this capability. The code can handle multiple branches in the flow. Using the converged flow field from this code, another program was written to perform a particle trajectory analysis. Numerical solutions were obtained on a supercomputer for a typical branched duct for which experimental flow and pressure measurements were also made. The flow separation zones predicted by the calculations were found to be in good agreement with those observed in the experimental tests. The total pressure recovery factors measured in the experiments were also compared with those obtained numerically. Within the limits of the grid resolution and the turbulence model, the agreement was found to be fairly good. In order to simulate the path of debris entering the duct, the trajectories of spherical particles of different sizes introduced at the inlet were determined.
Optimization of Gas Turbine HRSG Cycles Some Concepts
Authors: Pasha Akber 
Published: March 2015

Today the Heat Recovery Steam Generator (HRSG) has become an integral part of the combined cycle or Cogen plant because of its influence on other equipment. Therefore, the optimization of the HRSG has become one of the prime targets to improve the overall efficiency.
The paper presents recent developments and concepts used in HRSG design which improve either the efficiency or the range of performance or both. The paper discusses three major areas of a HRSG - Superheater/Reheater, Economizer, and LP Evaporator/Feedwater Preheater. Depending upon the requirement, the user can implement one or more of the concepts to improve the total performance and/or the reliability.
Further Technical Aspects and Economics of a Utility-Size Kalina Bottoming Cycle
Authors: Kalina A. I. , Leibowitz H. M. , Markus D. W. , Pelletier R. I. 
Published: March 2015

An 86 MW bottoming cycle has been designed based on the Kalina cycle principles previously reported by the authors. It is designated as Kalina Cycle System 6 (KCS6). It uses an ABB Type 13E gas turbine topping cycle to produce a 227 MW combined cycle having a heat rate (LHV) of 6460 Btu/kWh (52.8%). The working fluid is a 75% aqua ammonia mixture.
Equipment and installation costs were developed for KCS6 and a baseline two-pressure steam bottoming cycle. The KCS6 turbine was designed with input from ABB.
Compared to the two-pressure steam bottoming cycle, KCS6 provides an additional 12.1 MW (16.4%). The estimated cost of the bottoming cycle is $1,058/kW vs. $1,033/kW for the steam plant. The KCS6 heat acquisition equipment (boiler and recooler) and distillation/condensation subsystem represent the two major additions to cost over the steam plant. On the other hand, the turbine is less expensive, mostly due to the elimination of the large condensing stages.
An economic analysis of the KCS6 plant is presented using the value of the additional output as the decision-making economic variable. The analysis is based on a model which considers capital cost, heat rate and near-term world-wide fuel prices. At $4.25/106 Btu fuel, the KCS6 costs approximately $7 million less than the value of its output.
Advanced Turbine Technology Applications Project (ATTAP): Overview, and Ceramic Component Technology Status
Authors: Haley Philip J. 
Published: March 2015

The automotive gas turbine’s (AGT) significant potential payoffs in fuel economy, emissions, and alternate fuels usage continue to motivate development activities worldwide. The U.S. Department of Energy-sponsored, NASA-managed Advanced Turbine Technology Applications Project (ATTAP) focuses on developing critical AGT structural ceramic component technologies. The area of greatest challenge is that of cost-effective, near-net-shape, high-volume, high-yield manufacturing processes. Process physics modeling and Taguchi analyses are affording substantial progress, and new processes are being explored. Laboratory characterization is building a shared materials data base among Allison, Garrett, Government labs, and ceramic manufacturers. General Motors (GM) has logged over 700 test hours with ceramic components in hot gasifier rigs during ATTAP. A key ATTAP milestone was addressed by successfully demonstrating full goal temperature and speed (2500°F rotor inlet at 100% shaft speed) with ceramic components.
Fast-fracture ceramic component design tools are well correlated. Although time-dependent data and mechanistic models exist, a validated design system for such phenomena does not, and is a pressing need. Damage tolerance and impact resistance have been substantially addressed through tailored component designs, tougher monolithic ceramics, and increased ceramic strengths. Ceramic turbine rotors are now continuing to run after various substantial impacts, and after chipping damage. Ceramic-ceramic and ceramic-metal interfacing is being addressed by minimizing components’ joints, and by other DOE-sponsored work on joining models, processes, and materials.
The extruded regenerator disk is a continuing goal which requires both forming process and materials technology development. Controlling turbine tip clearances and tolerating tip rubs are key technologies. GM has demonstrated clearance control schemes, as well as rotor survivability to high speed/temperature tip rubs. Several noteworthy ceramic materials reflect the rapid progress over the past decade of monolithic ceramics, especially the Si3N4 family. GM forecasts achieving ATTAP engine cyclic durability goals.
Marine Gas Turbine Condition Monitoring by Gas Path Electrostatic Detection Techniques
Authors: Cartwright R. A. , Fisher C. 
Published: March 2015

It was discovered in 1970 that certain gas turbine failures are preceded by an increase in electrostatic activity in the exhaust gases. Joint research by the Royal Aerospace Establishment and Stewart Hughes Limited demonstrated that this characteristic could be used to provide an on-line monitor of the precursors to these failures. An extension of the research applied the theory to the detection of foreign objects ingested into engine inlets. The characteristics and performance of both the Ingested Debris Monitoring System (IDMS) and Engine Distress Monitoring System (EDMS) were examined during a recent 2000 hours endurance trial of a Rolls-Royce Marine Spey gas turbine.
The EDMS produced clear evidence of the minor combustor degradation that occurred steadily throughout the trial and also reflected the absence of other engine damage. IDMS data showed that few significant debris particles passed through the engine. Video endoscope and visual inspection confirmed these results. Debris seeding trials further explored the capability of the IDMS to identify the damaging nature of debris and to assess the EDMS signature of consequential engine damage.
The paper concludes that electrostatic monitoring at engine inlet and exhaust can identify the ingestion of debris, consequential engine damage and the onset of unexpected distresses caused by blade rubs or combustor degradation. The technique shows potential to provide early warning of certain types of engine damage to Engineer Officers at sea and development into a rugged gas path condition monitoring system continues.
Ceramic Candle Filter Performance at the Grimethorpe (UK) Pressurized Fluidized Bed Combustor
Authors: Stringer John , Leitch Alan J. 
Published: March 2015

A pilot hot gas particulate removal system based on positive porous ceramic filters has been tested on the Grimethorpe Pressurized Fluidized Bed Combustor facility. The filters are in the form of closed ended tubes, 1.5 m long: these are generally called ‘candles’. The dust accumulates on the outside of the candles, and is periodically removed by a pulse of air into the candle interior, which then flows outwards through the candle wall in the reverse direction to the normal flow of the combustion gas. The EPRI system contained a maximum of 130 candles, which is approximately equivalent to the requirement for 7 MW(e) capacity, depending on the filter operating parameters. The filter unit operated for a total of 860 hours under PFBC conditions, of which 790 hours were at defined process conditions, typically 850°C and 10 bar.
The amount of gas flowing through each filter element was varied, and the time between cleaning pulses was also varied. The pressure drop through each filter element rose as the dust accumulated on the outer wall, and recovered after the cleaning pulse. However, the post-cleaning pressure drop does not recover to the original clean candle value, but increases with time. It is believed that a steady-state value is attained, but the exposure in the Grimethorpe test series was insufficient to establish this unequivocally.
During the test, five candles failed. This appears to have been due to mechanical shock, as a result of candles lifting because of excessive pressure differentials across their support plate, and dropping back. The failures are not believed to be intrinsic to the technology. However, in addition a reduction in the strength of the candles with time of exposure was observed. This might also attain a steady state value, but this too could not be established on the basis of the tests reported in this paper. This is clearly a matter of importance, and further work will be required to determine the suitability of the clay-bonded silicon carbide medium used in these tests for this application.
A number of deficiencies in the design of the unit emerged with the operating experience, and suggestions have been made for improvements. However, it is clear that further work on design optimization is required.
The pulse cleaning air usage in the tests was greater than would be economically acceptable in a practical system. Further work needs to be done to optimize the cleaning cycle.
Overall, the test was very successful, and when operating properly the filters removed essentially all of the dust in the gas exiting from the combustor. Apart from the issues with the candle strength and the pulse cleaning air usage, the other problems were not believed to be of major importance in the further development of the technology.
This paper will summarize the test results, emphasizing the problems of candle durability and the pulse cleaning system.
Propulsion Aspects of Hypersonic Turbo-Ramjet-Engines With Special Emphasis on Nozzle/Aftbody Integration
Authors: Herrmann H. , Rick H. 
Published: March 2015

For hypersonic transport vehicles with combined turbo-ramjet engines operating in the Mach 0 to 6+ regime the exhaust nozzle/aftbody configuration is one of the most important areas. The variable and controllable hot gas single expansion ramp nozzles coupled with different bypass and boundary layer flows represent highly integrated propulsion/airframe-systems. These exhaust systems influence considerably the vectorial force and moment balance of the total aircraft.
This paper presents examples of some concept studies of generic nozzle configurations calculated by different computational fluid dynamic methods for selected flight regimes.
The following aspects are mainly discussed:
Bookkeeping system of the single expansion ramp nozzle and aircraft aftbody, the application of different CFD-codes, a critical comparison of typical examples and calculation methods and finally some considerations about future investigations and experimental correlation.
Joining of ODS-Superalloys
Authors: Hedrich H. D. , Mayer H. G. , Haufler G. , Kopf M. , Reheis N. 
Published: March 2015

A stable oxide dispersoid distribution in the metal matrix, a textured orientation and a coarse grain structure with high grain aspect ratio are characteristics of ODS-super-alloys. This grain structure is the reason for enhanced mechanical properties, oxidation and corrosion resistance at high temperature unobtainable in other superalloys. Therefore ODS-alloys are promising materials for advanced combustion engines and energy generation units. The ferritic ODS-alloy permits operating temperatures up to 1350°C.
In order to produce complex and high temperature resistant components suitable joining methods are technically and economically significant. This paper presents first results of investigations of joining the new iron-base-ODS-alloy PM 2000 developed by Metallwerk Plansee. The following joining techniques are under investigation: gas tungsten-arc welding, laser beam welding and electron beam welding as fusion welding techniques and diffusion bonding as a solid state joining technique. Joining is done in recrystallized and in unrecrystallized condition. Pre- and post-heat treatment procedures were applied and tested to improve the joint strength.
The Effect of Predeparture Training Loads on Posttour Physical Capacities in High-Performance Junior Tennis Players
Authors: Murphy Alistair P. , Duffield Rob , Kellett Aaron , Gescheit Dani , Reid Machar 
Published: March 2015

Purpose:Difficulties in preserving physical capacities while on tennis tours necessitate targeted training prescription. This study analyzed training and match loads performed before and on tour for their relationship with posttour physical-capacity changes. A secondary aim was to determine whether the presence of a strength and conditioning (S&C) coach affected the type and volume of on-tour training load.Methods:The training and match loads of 30 high-performance junior tennis players were recorded over 8 wk: 4 wk before and 4 wk during an international tour. Fitness tests were conducted pretour and posttour, including double and single-leg (dominant and nondominant) countermovement jump, speed (5, 10, and 20 m), modified 5-0-5 agility, 10 × 20-m repeated-sprint ability, and multistage fitness tests. Tour training and match loads were categorized according to whether S&C support was present or absent.Results:Total and tennis training loads were significantly greater on tour than pretour (P ≤ .05, d > 0.8). Increases in on-tour, on-court training loads were moderately correlated with decrements in speed and aerobic power (r = .31-.52). Finally, S&C presence on tour significantly increased total, on-court, and off-court training load completed (P ≤ .05, d > 0.8).Conclusions:Training loads should be carefully prescribed to ensure that sufficient total and tennis loads are completed pretour. Specifically, speed and aerobic capacities may regress with increased training on tour. Finally, a practical observation was that on-tour S&C support resulted in increased S&C training load (around match loads), potentially countering the observed regression of physical capacities. Such a finding has the capacity to alter current physical-preparation structures in high-performance tennis environments with finite resources.
Physiological Performance Determinants of a 22-km Handbiking Time Trial
Authors: Fischer Gabriela , Figueiredo Pedro , Ardigò Luca P. 
Published: March 2015

Purpose:To investigate physiological performance determinants of the partial laps and an overall 22-km handbiking (HB) time trial in athletes with high paraplegia.Methods:Seven male HB athletes with spinal cord injury (lesion levels thoracic 2-8) performed a laboratory maximal incremental test under cardiorespiratory-mechanical monitoring including respiratory-exchange ratio (RER), oxygen uptake (V̇O2), and mechanical power output (PO). Individual first and second ventilatory thresholds (V̇O2VT1 and V̇O2VT2), V̇O2peak, and POpeak were posteriorly identified. Athletes also performed a simulated HB time trial along a 4-lap bike circuit under cardiorespiratory measurement. Overall metabolic cost (C) and %V̇O2peak (ratio of V̇O2 to V̇O2peak) were calculated from race data. Race performance was defined as mean race velocity (v).Results:athletes completed the 22-km HB time trial in 45 ± 6 min, at 29.9 ± 3.6 km/h, with %V̇O2peak = 0.86 ± 0.10 and RER = 1.07 ± 0.17. V̇O2peak (r = .89, P = .01), POpeak (r = .85, P = .02), V̇O2VT1 (r = .96, P = .001), V̇O2VT2 (r = .92, P = .003), and C (2nd lap, r = .78; 3rd lap, r = .80; and 4th lap, r = .80) were significantly (P < .05) positively correlated with race performance. Within-subjects correlation coefficient revealed a large and significant (r = .68, P < .001) relationship between %V̇O2peak and v.Conclusions:V̇O2peak, POpeak, ventilatory thresholds, %V̇O2peak, and C appeared to be important physiological performance determinants of HB time trial.