bluuebunny/crossref_metadata_2025 huggingface dataset:
Environmental Impact of Public Charging Facilities for Electric Two‐Wheelers
Authors: Mendoza Joan‐Manuel F. , Josa Alejandro , Rieradevall Joan , Gabarrell Xavier
Published: April 2015

The environmental characterization of the charging infrastructure required to operate electric vehicles (EVs) is usually overlooked in the literature. Only rudimentary life cycle inventories of EV charging facilities are available. This lack of information is especially noticeable in environmental studies of the environmental performance of electric two‐wheelers (E2Ws), none of which have included an analysis of charging facilities, even though they constitute the most successful electric‐drive market in the world. This article focuses on characterizing the life cycle of the global warming potential (GWP) and primary energy demand (PED) of two conventional charging facility designs that are widely implemented for charging E2Ws in public spaces. The relative environmental relevance of charging facilities per kilowatt‐hour (kWh) supplied to E2Ws is determined by considering a range of use scenarios (variability in the service ratio) and the effect of upgrading the electricity mix to include more renewable energy sources. Savings of over 3 metric tons (tonnes) of carbon dioxide equivalent emissions and 56 equivalent gigajoules can be achieved by implementing an optimized charging facility design. The internalization of the relative environmental burden from the charging facility per kWh supplied to E2Ws can increase the GWP of E2Ws’ use phase from 1% to 20% and the PED from 1% to 13%. Although the article focuses on one particular case scenario, the research is intended to provide complementary criteria for further research on the life cycle management of electric mobility systems. Thus, a series of factors that can influence the environmental performance of EV charging networks at the macro scale are discussed.
Using a Rebound Matrix to Estimate Consumption Changes from Saving and its Environmental Impact in Japan
Authors: Kawajiri Kotaro , Tabata Tomohiro , Ihara Tomohiko
Published: April 2015

We investigate the extent to which Japanese people can change their consumption and the corresponding environmental impact. We propose a new analytical framework with a rebound matrix that captures the monetary flow from potential savings to their respending (referred to as rebound). A questionnaire is used to derive the matrix. On average, respondents spent 3.4 million Yen annually, resulting in 12.4 tons of carbon dioxide (CO2) emissions in their daily lives. The survey results suggest that acceptable spending reductions would correspond to a CO2emissions reduction of nearly 6%. However, the CO2emissions would increase by nearly the same amount when the respondents respend their savable money (rebound CO2emissions). The annual CO2emissions and the annually reducible CO2emissions both increase with the increase in annual expenditure. Consequently, the net CO2emissions also increase with the increase in annual expenditure. The rebound spending is approximated using the rebound matrix. Finally, it is suggested that the net CO2emissions can be reduced through lifestyle changes whereby spending on energy items is reduced and the resulting savings are spent on telecommunication, clothes, shoes, education, and housing.
Directions of Existence: Indigenous Women Domestics in the Paris of the Tropics1
Authors: Chernela Janet M.
Published: April 2015

Enquanto a maior parte da literatura sobre populações indígenas enfatiza o apego aos lugares, tomando qualquer movimento fora dos territórios tradicionais como uma perda de identidade, o caso da mobilidade das mulheres Tukano do Alto Rio Negro para a cidade de Manaus, no Brasil, ilustra a importância da mobilidade e agilidade, mais que permanência ou territorialidade, como importantes recursos. Fugindo de condições de trabalho forçado, as mulheres Tukano encontram na cidade vários meios de subsistência através de hábeis negociações de vários tipos. Este artigo revisa suas trajetórias urbanas, a partir da formação de uma organização sem fins lucrativos, a AMARN. Com base nesta associação, as mulheres encontram agência na criação de espacialidades que utilizam ao mesmo tempo a visibilidade do centro urbano e o anonimato da periferia. Ao defrontar‐se com os desafios da vida urbana, na cidade conhecida como a “Paris dos Trópicos”, as mulheres da AMARN direcionam ativamente sua própria existência.
Cytomegalovirus‐related childhood mortality in Australia 1999–2011
Authors: Smithers‐Sheedy Hayley , Raynes‐Greenow Camille , Badawi Nadia , Khandaker Gulam , Menzies Robert , Jones Cheryl A
Published: April 2015

Aim

Cytomegalovirus (CMV) is an important cause of congenital infection, which can result in neonatal deaths or contribute to deaths in later childhood. Post‐natally acquired CMV is a less common cause of disease and mortality, and only in preterm infants or immunocompromised children. Here we sought to describe CMV as a direct or secondary contributor to childhood mortality in Australia.

Method

We searched national mortality data sets between1999 and 2011 for cases <15 years with CMV recorded as an underlying or contributing cause of death.

Results

Eighty‐three CMV‐associated deaths in children <15 years were identified (0.2 cases per 100 000 <15 years; 95% confidence interval 0.16–0.24). Childhood deaths associated with CMV were evenly distributed between males and females, and the majority (n = 57; 68%) occurred in children less than 12 months of age, with 22 cases <1 month of age. Over the 13‐year study period, the mortality rate remained stable and CMV resulted in an estimated age‐adjusted 5925 years of potential life lost.

Conclusions

CMV makes a small but important contribution to childhood mortality in Australia. Most CMV‐related deaths occurred in infants <12 months of age. These infant deaths may be an indirect marker of the burden of severe intrauterine CMV disease given the natural history of this infection.
Adjunctive traditional Chinese medicine therapy improves survival of liver cancer patients
Authors: Liao Yueh‐Hsiang , Lin Cheng‐Chieh , Lai Hsueh‐Chou , Chiang Jen‐Huai , Lin Jaung‐Geng , Li Tsai‐Chung
Published: April 2015

Background

Traditional Chinese medicine (TCM) is an alternative treatment for cancer with its effect by stimulating host immune response for cytotoxic activity against liver cancer. No studies evaluated TCM treatment on survival of liver cancer patients.

Patients and methods

This study determined whether the combination of TCM and conventional cancer treatment affects the survival of liver cancer patients. A retrospective cohort study was conducted in 127 237 newly diagnosed liver cancer patients from 2000 to 2009 in the National Health Insurance Program database.

Results

Among these patients, 30 992 (24.36%) used TCM for liver cancer care. All patients were followed up until 2011. The mean follow‐up was 5.67 years (SD 1.47) for TCM users and 5.49 years (SD 3.64) for non‐TCM users. Compared with patients without TCM use, patients with TCM use were significantly associated with a decreased risk of death [hazard ratio (HR) = 0.65, 95% confidence interval (CI) = 0.64–0.66] with multivariate adjustment. A similar significant protective effect of TCM use across various subgroups of chronic liver diseases was also observed. Jia Wei Xiao Yao San (HR = 0.89, 95% CI = 0.81–0.96) and Chai Hu Shu Gan Tang (HR = 0.86, 95% CI = 0.78–0.95) were the most effective TCM agents that improved survival.

Conclusions

This cohort study provided information that adjunctive therapy with TCM may improve the survival in liver cancer patients. Further studies are needed to confirm the potential role of TCM in HCC.
High Relapse Rates Despite Early Intervention with Intravenous Methylprednisolone Pulse Therapy for Severe Childhood Alopecia Areata
Authors: Smith Alexandra , Trüeb Ralph M. , Theiler Martin , Hauser Valérie , Weibel Lisa
Published: April 2015

Background

Previous data suggest that early application of intravenous methylprednisolone pulse therapy (IV‐MPPT) may improve the disease course of alopecia areata. The objective of this study was to investigate the outcome of IV‐MPPT in severe childhood alopecia areata, predominantly with short disease duration.

Methods

Eighteen children (10 girls, 8 boys) younger than 17 years old (median age 7.7 yrs, range 2.1–16.5 yrs) treated with IV‐MPPT for severe childhood alopecia areata in a referral center for pediatric dermatology over 3 years (median disease duration 4 mos, range 1–12 mos) were retrospectively evaluated. Five patients had alopecia areata totalis or universalis and 13 had alopecia multilocularis. The median scalp area affected by alopecia was 60% (range 30%–100%). All patients underwent two or three cycles of IV‐MPPT at monthly intervals (maximum 500 mg/day on three consecutive days).

Results

Within 7 months after the last IV‐MPPT session, 10 of 18 children had good response (≥75% of hair regrowth), with eight showing improvement within the first 4 months. Of the remaining eight patients, one had moderate response (50%–74% regrowth), three had poor response (1%–49% regrowth), and four (all with alopecia areata universalis or totalis) had no response. Seven of the initial 10 good responders experienced relapses, with marked hair loss after the last IV‐MPPT session. The estimated median time to relapse was 8 months (95% confidence interval 7, 9 mos).

Conclusion

IV‐MPPT, even early in the course of disease, did not affect long‐term outcome of alopecia areata in our group of severely affected patients.
Use of non‐pharmaceutical interventions to reduce the transmission of influenza in adults: A systematic review
Authors: Smith Sheree M.S. , Sonego Sandra , Wallen Gwenyth R. , Waterer Grant , Cheng Allen C. , Thompson Philip
Published: April 2015

During seasonal influenza epidemics and pandemics, virus transmission causes significant public health concern. Reduction of viral transmission by non‐pharmaceutical interventions (NPI) has a significant appeal and is often recommended. However, the efficacy of such interventions is unclear. A systematic literature review was undertaken to identify and evaluate the published literature on NPI efficacy to prevent human transmission of influenza virus in adults. Reviewers assessed the quality of eligible studies utilizing the Critical Appraisal Skills Programme for bias and the Scottish Intercollegiate Guidelines Network for methodological quality. Studies were assessed for risk of bias domains of random sequence generation, allocation concealment, attribution bias, selective reporting and blinding. Relevant citations of 2247 were reduced to 100 for full‐text evaluation. Only seven met all selection criteria and pooled analysis was not feasible. Of the seven studies, two were randomized controlled trials (RCT) and five were cluster RCT. The main NPI studied were disinfection and hygiene; barriers; and combined NPI. However, these seven RCT had significant design flaws. Only two studies used laboratory confirmed influenza and poor statistical power was a major problem. Positive significant interventions included professional oral hygiene intervention in the elderly and hand washing. Despite the potential for NPI in preventing influenza transmission, there is very limited data available. Hand washing and dental hygiene may be useful, but other interventions have not been fully assessed. Properly designed studies evaluating large populations including ‘at risk’ patients and in a variety of communities are needed.
Students Talk About Prime: What We Heard About Definitions
Authors: Cavey Laurie , Kinzel Margaret , Walen Sharon , Rohrig Kathleen
Published: April 2015

This study examines data from college students who worked in pairs to make decisions about a list of potential definitions of prime number. Analysis focused on the evidence each student pair cited when they decided whether or not a statement could be used as a definition for prime number. The purpose of this paper is to describe patterns in the ways students used the evidence they cited. Findings suggest that students attend to important features of mathematical definitions, with some students giving preference to usability and others giving preference to definitions that are unambiguous.
Commercial Engine Logistics Cost Projections: A Dynamic and Flexible Approach
Authors: Cavoli N. C. , Rokicki G. J.
Published: April 2015

To determine the economic impact of various airlines’ maintenance policies and mission conditions, Pratt & Whitney Aircraft has developed and is currently using a flexible forecasting system. At the heart of this system is a computer simulation program designed to project engine shop visits and maintenance costs. These projections form the basis for numerous maintenance cost and reliability guarantees prevalent throughout the commercial airline industry. The computer program mathematically simulates engine operation at the part level using Weibull frequency distributions adjusted for airline maintenance practices and mission conditions. Once an accurate assessment of future engine shop visits is determined, accurate projections of additional logistics cost elements can be obtained. These elements include spare engines and modules, initial spare part inventory provisioning, overhaul shop facilities and engine tooling requirements. The benefits of this forecasting technology can be economically advantageous to the commercial airline operator in terms of financial planning and direct operating cost reduction.
Prediction of NOx Emissions
Authors: Lewis G. D.
Published: April 2015

A procedure has been developed for predicting the formation of NOx in gas turbine combustion systems operating at various conditions and on a variety of fuels, if the NOx produced by that engine is known for any one combination of fuel and operating condition. The predictions are based on a fundamental relationship between NOx formation and flame temperature with empirical adjustments for the special cases of fuel changes and water injection. Engine data indicate that the predictions are accurate within the data scatter limits that are normally encountered in engine field measurements. This work is not intended as a new kinetic model of NOx formation but rather as a useful tool for the engineer who has to predict what his engine will do under conditions where it has not yet been tested. It divides the NOx formation process into factors measurable by the engineer, i.e., flame temperature, pressure, and fuel flow rate, and shows how each of these contributes to the overall NOx in a predictable way.
Design Analysis of High-Efficiency Low-Stress Ceramic Gas Turbines
Authors: Wilson D. G. , Wood L.
Published: April 2015

The gains which can be realized in gas-turbine cycles by lowering the pressure ratio, increasing the degree of regeneration, and utilizing multistage compressors and turbines, are much increased design-point thermal efficiency; very much higher part-load efficiency; and much reduced centrifugal stress, attachment stress, and foreign-object-damage stress. These gains, and the size penalty associated with this approach, are evaluated to a first approximation. The net benefits should be substantial for many applications where size limits are not stringent, for instance trucks and boats, and where reduced fuel consumption is of paramount importance.
Design Concepts and Equipment Selection Processes for Northern Compressor Stations
Authors: Cleveland A. , Humphries E.
Published: April 2015

Development of gas supplies in the far north has focused attention on the design and construction of transportation systems to carry this gas from these remote regions to the markets in the industrial areas of North America. The need for high reliability of operation in remote areas under extremes of climatic conditions raises many problems. Principal among these are cold weather operation, accessibility, maintenance, transportation, seismic risk and environmental considerations. It is for these and other reasons that the selection of equipment to operate in a northern environment has to be approached systematically and thoroughly to ensure that flow of gas from the fields to the markets may be maintained under all possible conditions is the most economic manner and without interruption.
A Fast Numerical Procedure to Solve the Meridional Equations of Motion in a Multistage Axial Flow Turbomachine
Authors: Kündig A.
Published: April 2015

A new numerical procedure has been developed to solve the meridional equations of motion in an axial flow turbomachine. It is based on the so-called streamline-curvature method. The primary aim of this project was to reduce the computing-time of existing programs. The procedure has been tested. The new program is coupled with a program for the calculation of end-wall-boundary layers on axial flow compressors. This combination makes the simulation of real flow conditions possible. The pitch wise deviation angles and blade-row efficiencies are generally given as input. For compressor blades of the NACA-65-family they can be called from stored empirical data as function of geometry and the upstream and downstream flow conditions. The paper presents an exact description of the numerical procedure and a computed example.
Effects of Vitiation on Axial Catalyst Bed Temperature Profiles
Authors: Osgerby I. T. , Olson B. A. , Lew H. G. , Cohn A.
Published: April 2015

Studies have been conducted at Engelhard Research Laboratories under an EPRI sponsored subcontract from Westinghouse to experimentally determine performance characteristics of Catcom* catalysts at simulated gas turbine combustion conditions using No. 2 fuel. A comparison study was carried out using a 1-in. diameter laboratory reactor and a 9-in, diameter burner. 5-in. and 6-in, catalysts lengths were tested in the laboratory reactor and the 6-in, length in the burner. Effects of vitiated versus indirect preheat were investigated together with varying adiabatic flame temperature (based on fuel/air ratios), catalyst inlet reference velocity and catalyst length. Process variable upset conditions were simulated in the 9-in, burner and over fueling was simulated in the 1-in. reactor. The temperature profiles, combustion efficiencies and pressure drop data obtained can be used to assess performance of anticipated catalytic combustor designs for gas turbine systems. These results continue to show that CATCOM catalysts and the Catathermal* mode of combustion can be applied practically to large scale gas turbine equipment.
Aerodynamic Design and Experimental Study of Marine Gas Turbine Exhaust Volutes
Authors: Xingsu Lu , Kunyuan Pan , Zuomin Wu
Published: April 2015

The aerodynamic characteristics of the exhaust system have an important bearing on the economic aspects of the marine gas turbine. The exhaust volute is an important component of the exhaust system. The design of turbine exhaust volutes must take into account the structural demands of the gas turbine, the layout of the exhaust system as a whole in the engine room and the hull as well as its overall dimension requirements. This paper discusses the design principles of exhaust volutes. Given the hub-tip ratio dl/D1 of turbine exit (volute entry), a method is developed to rationally select the axial length L and radial width B. The selection of an annular diffuser and the relevant parameters along with the coordination of diffuser and collector are analyzed. On the basis of an analysis of experimental data the basic design criteria of exhaust volutes are proposed.
A Study of External Fuel Vaporization
Authors: Szetela E. J. , Chiappetta L. , Baker C. E.
Published: April 2015

A conceptual design study was conducted to devise and evaluate techniques for the external vaporization of fuel for use in an aircraft gas turbine with characteristics similar to the Energy Efficient Engine (E3). A second purpose of the study was to select the most favorable fuel vaporization concept. In the study, three candidate concepts were analyzed from the standpoint of fuel thermal stability, integration of the vaporizer system into the aircraft engine, engine and vaporizer dynamic response, startup and altitude restart, engine performance, control requirements, safety, and maintenance. The results of the study indicate that an external vaporization system can be devised for an E3 -type engine with hardware of reasonable size. The hardware can be packaged without increasing the total engine volume and the system is not unduly complex. The selected concept offers potential gains in engine performance in terms of reduced specific fuel consumption and improved engine thrust/weight ratio. The thrust/weight improvement can be traded against vaporization system weight. However, the vaporizer is subject to fouling with deposits formed at the walls exposed to heated fuel.
The Response of a Thermal Barrier System to Acoustic Excitation in a Gas Turbine Nuclear Reactor
Authors: Betts W. S. , Blevins R. D.
Published: April 2015

A gas turbine (GT) located within a High-Temperature Gas-Cooled Reactor (HTGR) induces high acoustic sound pressure levels into the primary coolant (helium). This acoustic loading induces high cycle fatigue stresses which may control the design of the thermal barrier system. This study examines the dynamic response of a thermal barrier configuration consisting of a fibrous insulation compressed against the reactor vessel by a coverplate which is held in position by a central attachment fixture. The results of dynamic vibration analyses indicate the effect of the plate size and curvature and the attachment size on the response of the thermal barrier.
The Ruston Tornado: A 6 MW Gas Turbine for Industrial Application
Authors: Wood G. R.
Published: April 2015

The paper describes the program to design and develop an efficient 6-MW simple open cycle gas turbine for service in gas compression, mechanical drive applications and power generation systems. The design philosophy of the package, a detailed description of the gas turbine, the component development programs together with their test results are presented. Plans for the introduction of the turbine package into field service in 1981 are outlined.
LM2500 Gas Turbines for Mobil Statfjord B Platform: The North Sea
Authors: Kiernan J. G.
Published: April 2015

The gas turbine compression and power generation systems for the Statfjord B platform required custom designed systems and significant design efforts. This paper summarizes many of the studies performed and reviews the overall project scope. The engineering considerations are presented to assist other gas turbine users and designers with their application considerations.
Water-Cooled Gas Turbine Forged Bucket Development
Authors: Collins M. F. , Schilke P. W.
Published: April 2015

This paper describes the materials and process development required to fabricate the third-stage bucket as part of the HTTT Phase II Program funded by the Department of Energy. The results of this materials engineering and process development work, including alloy selection, thermal mechanical processing, and deep hole drilling using Shaped Tube Electrolytic Machining (STEM), are presented. The mechanical properties of buckets fabricated as part of this program are discussed and compared to the overall third-stage bucket component design goals.
Material, Design, and Test Aspects of Ceramic Component Development
Authors: Richerson D. W. , Dins C. R. , Kington H. L. , Lindberg L. J. , Carruthers W. D. , Lane A. D.
Published: April 2015

The paper will describe component development conducted under the DARPA/Navy/Garrett Ceramic Turbine Engine Demonstration Program. Aspects of interactive/iterative design, material processing development, and component testing will be emphasized and illustrated by examples from the program. Successful rotor design, development, and demonstration will be discussed. Successful static structure component development will also be discussed, along with contact stress problems encountered at some static structure interfaces during engine testing.
Contamination of Centrifugal Process Gas Compressor Lube Oil and Seal Oil Systems by Hydrocarbon Condensate
Authors: Cootes L.
Published: April 2015

In the wake of gas compression offshore the problem of contamination of Seal Oil and Lube Oil systems by the process gas has posed particular problems. These difficulties stem chiefly from the uniqueness of the offshore situation, viz.: The inability to “waste” contaminated seals return because of an uncertain supply situation (oil inventory bunkered by boat) and the twin constraints of weight space restrictions imposed by offshore design. “In situ” treatment of relatively large volumes of contaminated Lube Oil and Seal Oil on offshore platforms is possible using the method described in this paper.
Progress in the Development of the Marine Spey, SM1A
Authors: Williams D. E.
Published: April 2015

The product is a fully marinised propulsion module derived from the TF.41, which is an aero engine jointly developed by Rolls-Royce and the Detroit Diesel Allison Division of General Motors. The design was described in an ASME paper in 1978. The launch is funded by the UK Ministry of Defence. The status of the program has now passed the point at which the design was committed and production modules, now on order are scheduled for delivery early in 1983. The history of the development of this 12 3/4 MW propulsion module is traced and the achievement reviewed in terms of the design concept.
HTGR-GT Primary Coolant Transient Resulting From Postulated Turbine Deblading
Authors: Cadwallader G. J. , Deremer R. K.
Published: April 2015

The turbomachine is located within the primary coolant system of a nuclear closed cycle gas turbine plant (HTGR-GT). The deblading of the turbine can cause a rapid pressure equilibration transient that generates significant loads on other components in the system. Prediction of and design for this transient are important aspects of assuring the safety of the HTGR-GT. This paper describes the adaptation and use of the RATSAM program to analyze the rapid fluid transient throughout the primary coolant system during a spectrum of turbine deblading events. Included are discussions of (1) specific modifications and improvements to the basic RATSAM program, which is also briefly described; (2) typical results showing the expansion wave moving upstream from the debladed turbine through the primary coolant system; and (3) the effect on the transient results of different plenum volumes, flow resistances, times to deblade, and geometries that can choke the flow.
Engine Cycle Selection for Advanced Technology Engine Studies
Authors: Lehman C. L. , Crafa V. J.
Published: April 2015

Methodology for selecting cycle parameters using advanced technology engine data is presented. This method was developed and refined during airframe design studies which used engine data designed to reduce the cost of ownership of new engines. Conventional methods of engine cycle selection are supplemented with additional parameters which weighed engine acquisition and operational costs. Using these data, aircraft performance and size penalties could be evaluated relative to overall system cost. Study results are shown for several high performance aircraft which are being evaluated as part of the joint USAF/USN Advanced Technology Engine Studies.
Field Experience With Gas Turbine Inlet Air Filtration
Authors: Pulimood M. K.
Published: April 2015

This paper outlines the field experience gained from the modular retrofitting of four gas turbine inlet systems with a second stage high efficiency media filter to reduce gas turbine fouling conditions. The original gas turbine inlet systems were furnished with inertial filters. Within a few thousand hours of operation considerable gas turbine performance loss had occurred. Field inspection revealed excessive fouling of the gas generator axial compressor sections, and crusty dust particle build up within the gas turbine internals and thermocouples. A second-stage high efficiency media filter was retrofitted, to capture the fine dust particles that passed through the inertial filters. Follow-up inspection of the two-stage filter systems, after about 8000 hr of operation, disclosed little indication of the engine fouling conditions that were present prior to the retrofitting.
Evaluation of the Impact on CGT Operation When Converting to Crude Oil Fuel
Authors: Meyer J. H.
Published: April 2015

The present energy availability and pricing situation has caused many users to consider the use of less refined fuels for combustion gas turbines. The use of these fuels will have a definite impact on the cost of operation and unit availability. It is necessary that a user be aware of the extent of this impact prior to making the decision to convert to a lower quality fuel. This paper discusses the method employed by one user to evaluate this impact and presents the results that were obtained.
Mechanical Design of a High Efficiency 7.5 MW (10,000 HP) Gas Turbine
Authors: Van Buijtenen J. P. , Farrell W. M.
Published: April 2015

This paper describes the mechanical design features on TF-10 gas turbine. The TF-10 gas turbine features an intercooled centrifugal compressor and an annular combustor. A regenerator is added as a standard item. The ISO rating is 7.5 MW (10,000 hp) with a rotor inlet temperature (RIT) of 1116 C (2042 F) and a thermal efficiency of approximately 44 percent. Description of the combustion, rotors, stators, bearings and shafting is presented.
Theoretical Study of Flow Instabilities and Inlet Distortions in Axial Compressors
Authors: Ferrand P. , Chauvin J.
Published: April 2015

This paper describes a method of evaluation of the single and multistage compressors response to steady and unsteady inlet distortions. It allows also the evaluation of the appearance of unstable regimes and their characterization (rotating stall and surge). It is based on a linearized approach using mean line calculations. The compressor is considered as a serie of vaned and vaneless spaces, and the corresponding equations are solved by use of Fourier series for time independent variables and by Laplace’s transform for time dependent variables. An analogy between the compressor’s response and a servo-mechanism is developed, using Nyquist’s diagram. Results are compared with experimental data which prove the validity of the approach. A parametric study indicates which parameters can be modified to improve the flow stability.
The Quantitative Analysis of Three-Dimensional Displacement Fields by Single Laser Hologram
Authors: Ji-sheng Zhong , Li-cha Zhou , Shi-jie Yang , Ji-lien Ren
Published: April 2015

A new holographic interferometry which adopted a new test apparatus — JQD-1 Three-Dimensional Laser Holographic Fringe Reader — has been proposed. The variation of viewing directions and corresponding fringe order numbers could be determined accurately by this Reader and the three cartesian components of object point deformation could be determined by single laser hologram. The reliability of this holographic interferometry has been verified by an experiment. The results obtained are compared with those from finite-element analysis.
The Use of Mathematical Modeling in the Analysis of Gas Turbine Compressor Unit Test Data
Authors: Williams L. J.
Published: April 2015

A clear need exists for methods of establishing the validity of gas turbine performance test results and diagnosing the causes of performance problems. Published methods depend on the results of simulating faults in complex mathematical models of the engines and are only capable of diagnosing combinations of faults previously simulated. A very simple mathematical modelling procedure is described which allows the analyst to test his own hypothesis of engine faults and so identify instrumentation errors and discover conditions not previously considered. Application of modelling to actual test data is demonstrated.
Analytical Consideration of Fuel Economy and Dynamic Response of a Regenerative High Temperature Autombile Gas Turbine: Part II
Authors: Takeuchi T. , Itoh T. , Ishida T.
Published: April 2015

A conceptual design study of a regenerative high temperature gas turbine and the dynamic characteristics of a regenerator were discussed in Part I of this paper in 1979. (ASME Paper 79-GT-127). In order to further study the characteristics of the ceramic gas turbine, a mathematical model for a gas turbine vehicle system was constructed on a hybrid computer, and the dynamic characteristics of a two-shaft regenerative gas turbine were calculated. We also calculated the 10-mode fuel economy for various control systems.
Control System for the Mainline Gas Turbines and Crude Oil Pumps on the Saudi Arabian Petroline
Authors: Stasiowski C.
Published: April 2015

The paper presents an overview of the system employed to control the mainline gas turbines and crude oil pumps used on the 747 mile East-West Petroline. Various operating modes such as starting, stopping and fuel transfers for normal and emergency operation are discussed. Particular attention is focused on the various fuel systems as well as a review of the major design problem areas and solutions. The results of a system test and the integration of each unit into the overall pipeline control scheme are included for completeness.
Improved Jet Engine Maintenance Through Automated Vibration Diagnostic Systems
Authors: Rio R. A.
Published: April 2015

The rapidly increasing cost of maintenance, the demand for increased equipment utilization, fuel costs, and the difficulty of correctly diagnosing internal mechanical problems in fully assembled jet engines, have stressed the need for more effective engine test equipment. This paper describes the successful application of both a component (module) high-speed balancing technique and an Automated Vibration Diagnostic System (AVID) in the U.S. Air Force’s high-volume engine overhaul center at Tinker Air Force Base, Oklahoma. the AVID concept to automate troubleshooting procedures for fully assembled rebuilt engines is addressed. This system extracts high frequency vibration data from existing standard instrumentation, thereby providing meaningful mechanical information. A growing appreciation on the part of engine overhaul personnel of the power of automated test equipment has enabled these key features to be combined to reduce operating expenses at engine rebuild facilities.
High Temperature Removal of Alkali and Particulates in Pressurized Gasification Systems
Authors: Mulik P. R. , Alvin M. A. , Yannopoulos L. N. , Ahmed M. M. , Ciliberti D. F.
Published: April 2015

Extensive thermodynamic and preliminary experimental studies have identified the potential use of aluminosilicate materials to simultaneously remove volatile alkali and particulate released during pressurized gasification of coal. The gettering capacity of three selected materials have been evaluated in a bench-scale reactor operating at 1114 kPa total pressure and 1123–1173K in alkali-laden inert, and simulated fuel gas environments. At 1123 K, alkali gettering has been established to result through reaction within the amorphous acid-insoluble alumino-silicate fraction of these materials, while at 1173 K saturation of the insoluble matrix is achieved, with gettering occurring mainly through acid-soluble complexes. The gettering mechanism as either a chemical reaction or a physical adsorption phenomenon and reaction kinetics will be delineated through future thermogravimetric (TG) analyses.
Streamwise Flow and Heat Transfer Distributions for Jet Array Impingement With Crossflow
Authors: Florschuetz L. W. , Truman C. R. , Metzger D. E.
Published: April 2015

Two-dimensional arrays of circular jets of air impinging on a heat transfer surface parallel to the jet orifice plate are considered. The air, after inpingement, is constrained to exit in a single direction along the channel formed by the surface and the jet plate. The downstream jets are subjected to a crossflow originating from the upstream jets. Experimental and theoretical results obtained for streamwise distributions of jet and crossflow velocities are presented and compared. Measured Nusselt numbers resolved to one streamwise hole spacing are correlated with individual spanwise row jet Reynolds numbers and crossflow-to-jet velocity ratios. Correlations are presented for both inline and staggered hole patterns including effects of geometric parameters: streamwise hole spacing, spanwise hole spacing, and channel height, normalized by hole diameter. The physical mechanisms influencing heat transfer coefficients as a function of flow distribution and geometric parameters are also discussed.
Three-Dimensional Aerodynamic Characteristics of Oscillating Supersonic and Transonic Annular Cascades
Authors: Namba M. , Ishikawa A.
Published: April 2015

A lifting surface theory is developed for unsteady three-dimensional flow in rotating subsonic, transonic and supersonic annular cascades with fluctuating blade loadings. Application of a finite radial eigenfunction series approximation not only affords a clear insight into the three-dimensional structures of acoustic fields but also provides mathematical expressions advantageous to numerical work. The theory is applied to oscillating blades. Numerical examples are presented to demonstrate three-dimensional effects on aerodynamic characteristics. Three-dimensional effects in supersonic cascades are generally small and strip theory predicts local aerodynamic forces as well as total aerodynamic forces with good accuracy. In transonic flow, however, the strip theory approximation breaks down near the sonic span station and three-dimensional effects are of primary importance.
Jet-Wake Analysis for Centrifugal Compressor Static Pressure Rise and Deviation Angle
Authors: Pampreen R. C.
Published: April 2015

This paper discusses the static pressure recovery characteristics of four different centrifugal compressor impellers. Comparison is made to effectiveness values obtained with rectangular and conical diffuser data. Effectiveness levels comparable to the diffuser data occur up to the point of maximum flow path curvature. In the radial portion of the impellers, rotation affects static pressure recovery. Also presented are values of rotor exit deviation angle deduced from the jet-wake analysis of these four impellers. It was found that deviation angle is only a function of blade exit angle. The sensitivity of the value of calculated deviation angle to the magnitude of assumed aerodynamic blockage is discussed. For the jet-wake model, the deviation angle is zero for blade exit angles of thirty degrees.
Interaction of Upstream Flow Distortions With High Number Cascades
Authors: Englert G. W.
Published: April 2015

This analytical study models features of the interaction of flow distortions, such as gusts and wakes, with blade rows of advance type fans and compressors having high tip Mach numbers. A typical disturbance is described, at afar upstream location, in three orthogonal spatial coordinates by a double Fourier series. It is convected at supersonic velocity relative to a linear cascade described as an unrolled annulus. Details of interaction of the disturbance with an in-passage shock are discussed. Influences of amplitude, wave length, and phase of the disturbance on lifts and moments of cascade configurations are presented.
Experimental Study and Theoretical Prediction of Secondary Flows in a Transonic Axial Flow Compressor
Authors: Leboeuf F. , Bario F. , Boris G. , Papailiou K. D.
Published: April 2015

Detailed time-mean measurements have been realized on a transonic axial flow compressor. Flow quantities in the secondary flow regions have been obtained. The purpose of this paper is to present some essential features which drive the secondary following development in axial compressor among others, the strong influence of secondary vortex motion on the energy transfer between the flow and the blading is displayed. Also, we study the effect of tip clearance and axial distance between blade row. A secondary flow model is used for comparisons with theoretical computations. Very good comparisons have been obtained which show the validity of the theoretical model, in particular, the decomposition of the secondary flow into a viscous part and a vortical part, using an inviscid flow as a basis.
The Use of Optimization Techniques to Design Controlled Diffusion Compressor Blading
Authors: Sanger N. L.
Published: April 2015

A method is presented for automating compressor blade design using numerical optimization, and is applied to the design of a controlled diffusion stator blade row. A general purpose optimization procedure is employed, which is based on conjugate directions for locally unconstrained problems and on feasible directions for locally constrained problems. Coupled to the optimizer is an analysis package consisting of three analysis programs which calculate blade geometry, inviscid flow, and blade surface boundary layers. The optimization concepts are briefly discussed. Selection of design objective and constraints is described. The procedure for automating the design of a two-dimensional blade section is discussed, and design results are presented.
A Method for Inverse Aerofoil and Cascade Design by Surface Vorticity
Authors: Lewis R. I.
Published: April 2015

Surface vorticity theory, normally considered as an analysis tool, has been modified to operate as a design tool whereby the shapes of components may be found to produce a prescribed surface velocity in incompressible flow. The basis of the method is presented and checked against classical solutions for cylindrical and diamond shaped struts with fully attached flow. A procedure for turbomachine blade or aerofoil design is outlined and illustrated with back checks via Martensen’s method. The method allows specification of velocity distribution on either or both surfaces of the body. If only one surface of an aerofoil or blade is prescribed, the user is allowed to specify profile thickness also.
Ruhrchemie/Ruhrkohle’s Technical Version of the Texaco Coal Gasifier as Part of a Combined Cycle Plant
Authors: Cornils B. , Hibbel J. , Ruprecht P. , Dürrfeld R. , Langhoff J.
Published: April 2015

The Ruhrchemie/Ruhrkohle variant of the Texaco Coal Gasification Process (TCGP) has been on stream since 1978. As the first demonstration plant of the “second generation” it has confirmed the advantages of the simultaneous gasification of coal: at higher temperatures; under elevated pressures; using finely divided coal; feeding the coal as a slurry in water. The operating time so far totals 9000 hrs. More than 50,000 tons of coal have been converted to syn gas with a typical composition of 55 percent CO, 33 percent H2, 11 percent CO2 and 0.01 percent of methane. The advantages of the process — low environmental impact, additional high pressure steam production, gas generation at high pressure levels, steady state operation, relatively low investment costs, rapid and reliable turn-down and load-following characteristics — make such entrained-bed coal gasification processes highly suitable for power generation, especially as the first step of combined cycle power plants.
HC and CO Emission Abatement via Selective Fuel Injection
Authors: Bahr D. W.
Published: April 2015

The results of investigations to develop carbon monoxide (CO) and unburned hydrocarbons (HC) abatement methods for use in aircraft turbofan engines are reviewed. Specifically, the use of selective fuel injection patterns at ground idle operating conditions in CF6 engines was assessed and evolved in combustor and engine tests. These fueling patterns were obtained by valving fuel to selected combinations of fuel nozzles at idle, rather than to the full complement of engine fuel nozzles, and were intended to provide localized fuel-air ratio enrichment within the combustor annulus. In addition to the effects of such fueling patterns on HC and CO levels, their effects on engine performance at starting, sub-idle, and idle conditions were determined. The use of repetitive clusters of fueled nozzles around the combustor annulus was determined to provide the best overall emission abatement, performance, and operational characteristics.
Status Report of the USAF’s Engine Model Derivative Program
Authors: Coalson M. S.
Published: April 2015

An investment strategy, known as the Engine Model Derivative Program has resulted in the prototype development of a new fighter engine, a new turboprop engine and promises the future development of a second fighter engine. The rationale for prototype, rather than full-scale development is presented and a brief overview of the F101 Derivative Fighter Engine, XT56-100 and F100 Advanced Derivative is described.
Fired Heater Versus CCGT/Cogeneration Cycle Parameters
Authors: Campbell J. , Lee J. C.
Published: April 2015

The coal-fired, closed-cycle gas turbine (CCGT) heat engine cycle is being developed for the cogeneration of process heat and power. The coal burning heater that provides the heat input to the gas turbine cycle is one of the more costly and technically challenging components of such systems. This paper discusses the interrelationships between the technical and economic feasibility of the heater and the CCGT cycle parameters, i.e., temperature, pressure ratio, working fluid, pressure level, etc. A mathematical relationship between the cycle parameters and the heaters’ working fluid side heat transfer coefficient is presented. Conclusions are presented regarding the zones of applicability of the available heater concepts to the spectrum of possible CCGT cycle parameters.
An Assessment of Erosion in PFBC Power Plant Turbines
Authors: Wenglarz R. A. , Schneider S. J.
Published: April 2015

Using a turbine erosion damage model and data from PFBC (pressurized fluidized bed combustion) pilot plant/cascade experiments, combustion turbine blade erosion rates and maintenance intervals for blade replacements are projected for a PFBC power plant system. The power plant includes a 10 atmosphere PFBC boiler with a matching 10:1 pressure ratio turbine and a gas cleanup system to remove particulates from combustor product gases before entering the turbine. Effects on turbine erosion of three alternative particle cleanup systems are evaluated. Blade replacement intervals due to erosion are found for the alternative gas cleanup systems.
Adaptive Fuel Control Feasibility Investigation for Helicopter Applications
Authors: Morrison T. , Howlett J. J. , Zagranski R. D.
Published: April 2015

A United States Army-sponsored, computer-aided study of a twin engine helicopter is being conducted to determine the feasibility of incorporating into the engine microprocessor-based control system, airframe signals and control strategies that improve helicopter capability. Investigations are considering on-line changes to the control characteristics which adapt to abnormal engine operation due, for example, to engine deterioration, surge or failure. The anticipation of power recovery from a split needle condition is accomplished with rotor speed feedback which allows increased transient load factors and improved handling qualities in maneuvering flight. For minimum fuel consumption in cruise, the control will seek the optimum rotor speed. An improvement in torsional damping is achieved with software filters which reduce the dependability of the drive train stability on the blade lag dampers. Studies to date indicate that there may be substantial payback in implementing these new control features.
Gas and Steam Turbines for District Heating
Authors: Oliker I.
Published: April 2015

Technical and economic aspects of utilization of steam and gas turbine plans for district heating are presented and discussed. Combined use of these plants for heat and electrical generation is considered. Advantages of flexible and combined operation, wide load variation and increase of the district heating supply temperature are presented and discussed.