bluuebunny/crossref_metadata_2025_split huggingface dataset:
Malignant mesenchymoma with widespread metastasis including bone marrow involvement in a dog
Authors: Weishaar Kristen M. , Edmondson Elijah F. , Thamm Douglas H. , Olver Christine S. 
Published: July 2014

AbstractA male castrated Golden Retriever was presented for evaluation of a large mass over the left shoulder extending to the lower part of the neck that had been present for an extended period of time, but had a recent history of rapid growth. Previous aspirates of the mass were consistent with a lipoma. The mass was surgically excised and was diagnosed as an extraskeletal osteosarcoma based on histopathology. After surgery, the dog was initiated on a chemotherapy protocol with carboplatin and metronomic cyclophosphamide. He became neutropenic, anemic, and thrombocytopenic 14 days after the carboplatin treatment was administered. The neutropenia resolved, but the anemia and thrombocytopenia progressed. A bone marrow aspirate revealed erythroid hypoplasia, myeloid hyperplasia with a predominance of early precursors, and a subset of cells that made up 20% of the total population that were reported as bizarre and unclassifiable. These cells were discrete in nature and were thought to be hematopoietic in origin. The dog was euthanized due to deterioration of the clinical condition. On postmortem examination, widespread metastasis involving the lungs, liver, kidney, heart, and bone marrow was found. Histopathology of the tumor lesions determined 2 distinct malignant populations of liposarcoma and osteosarcoma, consistent with malignant mesenchymoma. However, the possibility of 2 separate neoplastic processes cannot be definitively excluded. This is the first report of bone marrow metastasis of a malignant mesenchymoma in a dog.
Revisiting the Inhibition of Vanadium-Induced Hot Corrosion in Gas Turbines
Authors: Rocca Emmanuel , Steinmetz Pierre , Moliere Michel 
Published: July 2014

Since the 70’s, nothing substantially new has been published in the Gas Turbine Community about the hot corrosion by vanadium and its inhibition, after the “inhibition orthodoxy” based on the formation of magnesium vanadate, was established. However, the experience acquired since the late 80’s with Heavy Duty Gas Turbines burning ash-forming fuels in Southern China, shows that the combustion of very contaminated fuels does not entail corrosion nor abundant ash-deposit on gas turbines buckets. Analyses of deposits collected from gas turbines fired with these crude oils showed that the ash-deposit contains a large amount of nickel.
These new facts led to revisit the role played by nickel and envisage its possible inhibiting action against the vanadium-induced hot corrosion. A thorough review of the literature on the vanadium-induced corrosion have been carried out, and the study of the nickel effects with respect to magnesium effects on the ash deposit have been performed
Results show that nickel presents an interesting way to substitute magnesium for the inhibition of vanadium-induced hot corrosion. The advantages of nickel with respect to magnesium are to be efficient at a low Ni/V ratio, to produce less abundant, less adherent ash and to act, to some extent, as a self-cleaning agent for the blades of the turbine.
Materials Compatibility With Pyrolysis Biofuel
Authors: Kirk D. W. , Li Z. R. , Fuleki D. , Patnaik P. C. 
Published: July 2014

The conversion of biomass such as wood and wood byproducts via pyrolysis into a liquid fuel is important in maximizing the use of material resources and in providing alternative and renewable sources of energy. Pyrolysis oils (or biofuels) have good combustion characteristics but are compositionally different from conventional diesel fuels. This difference requires that materials in contact with the biofuel be tested for compatibility. Three types of biofuels were tested for compatibility with a variety of polymeric materials and metal alloys. The test temperatures were set at 80°C to represent aggressive field usage conditions. The tests were conducted using coupons, which were fully immersed in the fluid for periods up to 15 days.
These tests revealed that the metals 304L stainless steel, 316L stainless steel, 430 stainless steel and 20M04 stainless steels had corrosion rates of less than 0.007 mm/y and are suitable for use with the oils tested. A non-traditional low chromium alloy steel, MASH, was also examined and was found to be highly susceptible to all fuels at the high temperature tested and corroded at rates up to 3.7 mm/y. At room temperature, the alloy showed good resistance with a corrosion rate less than <0.009 mm/y.
The polymeric materials showed a wide range of properties in the oils tested. Non-elastomers such as polytetrafluoroethylene, polypropylene and high-density polyethylene in general showed little swelling or staining in the oils. The elastomeric materials were much more susceptible to swelling, weight gain and change of surface properties. The attack on elastomeric materials was quite rapid with significant volume expansion seen within 24 hours. Viton, Buna-N and EPDM had volume changes up to 100% during a 10-day test and were not considered suitable seal materials for these oils.
Multiple day tests for the low alloy steel at 80°C revealed that the corrosion attack was linear in nature leaving a corrosion scale, which slowed but did not prevent further attack. Details of the material degradation will be discussed.
Simulation of the WR-21 Advanced Cycle Engine
Authors: Biraud Benoit , Despierre Arnaud , Gayraud Stephane 
Published: July 2014

Representative simulation of gas turbine operation has to be performed by engine manufacturers during engine development programs for a number of reasons, including technical risk mitigation, safety analysis and cycle optimisation.
Minimisation of Specific Fuel Consumption (SFC) is the main challenge faced by the WR-21 engine, an intercooled and recuperated gas turbine which is at the forefront of future naval propulsion systems. Steady state simulation tools need to be developed to accurately predict engine performance under any set of environmental conditions. The methodology used involves an integrated “analysis-synthesis” simulation technique where extensive test data analysis is built into a full thermodynamic model of the engine.
Simulation of the gas turbine behaviour under transient conditions is also required to ensure maximum operability through optimised control, and gas turbine stability under any circumstances. For the WR-21 engine this simulation capability has been developed in both Real Time (RT) and Non-Real Time (NRT) modes. This process is particularly challenging for such an advanced cycle gas turbine where the number of components, and their thermodynamic interaction, is far greater than for a simple cycle prime mover.
This paper examines how these challenges have been successfully overcome by the WR-21 project. It describes the tools and techniques that have been developed in the project, and exemplifies their application through demonstration of significant technical achievements.
It also expands on the strategic issue of model flexibility and connectivity, and elaborates on future developments in simulation techniques, that will drive the naval gas turbine industry towards continual process improvement, ever closer to its customers.
Code-in-the-Loop Simulation for Embedded Software Development
Authors: Jaw Link C. , Wu Dong N. 
Published: July 2014

Control or monitoring logic development typically follows the process of model building, analysis, design, and (nonlinear) simulation. After the logic is verified in computer simulation, the corresponding embedded control or monitoring code is generated and downloaded to the controller’s microprocessor. Then a hardware-in-the-loop (HITL) simulation is conducted to verify the logic and the controller interface. Although this process is well established, the requirements for real-time simulation and hardware/software integration often pose a high risk in the embedded software development process. This risk can be mitigated by the code-in-the-loop (CITL) simulation methodology presented in this paper.
This CITL simulation methodology has been applied to a software update of the full-authority digital engine control (FADEC) unit for the Honeywell (formerly AlliedSignal) Universal Jet Air Starter Unit (UNIJASU), which is a gas turbine engine packaged as an auxiliary power unit to jump start aircraft engines on the ground. The CITL simulation, although non-real time, successfully predicted the effects of several control logic options and facilitated the implementation of software update. Hence we recommend that the CITL simulation be incorporated in the embedded control software development process to shorten software update time. We further recommend that CITL be a necessary step in the process if HITL simulation is not feasible.
Performance of a Dry Low-NOx Gas Turbine Combustor Designed With a New Fuel Supply Concept
Authors: Wakabayashi Tsutomu , Ito Seiichi , Koga Shonosuke , Ippommatsu Masamichi , Moriya Koji , Shimodaira Kazuo , Kurosawa Yoji , Suzuki Kazuo 
Published: July 2014

This paper describes the performance of a dry low-NOx gas turbine combustor designed with a new fuel supply concept. This concept uses automatic fuel distribution achieved by an interaction between the fuel jet and the airflow. At high loads, most of the fuel is supplied to the lean premixed combustion region for low-NOx, while at low loads, it is supplied to the pilot combustion region for stable combustion.
A numerical simulation was carried out to estimate the equivalence ratio in the fuel supply unit. Next, through the pressurized combustion experiments on the combustor with this fuel supply unit using natural gas as fuel, it was confirmed that NOx emissions were reduced and stable combustion was achieved over a wide equivalence ratio range.
Autoignition Characteristics of Gaseous Fuels at Representative Gas Turbine Conditions
Authors: Goy C. J. , Moran A. J. , Thomas G. O. 
Published: July 2014

The autoignition properties of gas turbine fuels have been studied for many years and by numerous researchers. The advent of ultra low emission industrial gas turbines using lean premixed technologies has given rise to premixer designs with longer residence times. This, in conjunction with the ever-increasing pressure ratios of aeroderivative machines, leads to the potential for autoignition within premix ducts, and has therefore renewed the interest in this field. Although much has been published, data in the region of interest to high pressure ratio gas turbines is extremely sparse. Similarly, modelled autoignition delay times are not very accurate, as most reaction mechanisms were not generated to cover this range of conditions. Hence the uncertainties of autoignition delay times at gas turbine conditions are significant, thereby either imposing over-stringent design limitations or introducing risks of ignition occurrence in the early design process.
A series of experiments have been carried out for methane and simulated natural gas fuels in the region of interest, using shock tubes as the test vehicle. The experimental technique was chosen to isolate only the chemical kinetic component of the autoignition delay time, without any additional delays due to mixing and heating of the test gases. Predictive correlations and a chemical kinetic model (the GRI mechanism) have also been used to predict autoignition delay times at the same conditions. The correlation between experiment and prediction has been shown to be poor at representative temperatures. This paper discusses some of the possible explanations for this poor agreement.
Scaling From Atmospheric Pressure Rig to Full-Scale Pressure for the Emission Measurements From a Gas Turbine Combustor
Authors: Martelli F. , Riccio G. , Benelli G. , Cecchini D. , Carrai L. 
Published: July 2014

Investigating the pressure scalability of pollutant emissions from a heavy-duty diffusion flame type, natural gas fuelled gas turbine combustor a two steps approach is presented in the current paper. First a theoretical viewpoint is established using similitude theory to characterize the operation conditions chosen for atmospheric tests in relation to the real gas turbine pressurized conditions. Then the corresponding experimental tests are presented for the full-scale gas turbine combustor in the original version both under atmospheric and pressurized gas turbine conditions at the ENEL test facilities.
The results from the theoretical study indicate, that similitude cannot be maintained rigorously between the atmospheric and pressurized tests. However the experimentally determined NOx-emissions obtained under the reduced similarity test conditions provide a pressure scaling relation that can be maintained between the original and the retrofitted version of the combustor.
Carbon Deposits in Gas Turbine Injectors
Authors: Tidjani N. , Martin G. H. , Ropital F. , Grienche G. , Verdier H. 
Published: July 2014

The formation of carbon deposits in gas turbines is a recurring problem to which a lot of important work has been dedicated. These deposits cause a lot of problems and have a direct impact on the performance of gas turbines both from an environmental point of view and on the energetic efficiency and on hot parts life. In the combustion chambers of gas turbines, two different types of deposits may appear, one inside the fuel injectors and the other in the flame tube. The understanding of the formation of these deposits as well as their characterization is of up most importance for the design of the combustion chambers of gas turbines.
The study presented in this paper summarizes the recent work carried out in IFP (Institut Français du Pétrole) on the formation of these deposits on the materials currently used in the design of the combustion chambers and injectors of gas turbines. A micro-pilot thermogravimetric unit operating at cracking temperatures to the order of 900°C allows us to define the parameters influencing the formation of these deposits. Thus, the influence of the nature of the material, of the composition of the charge and of the operating conditions (temperature, flow rate,…) on the formation of the deposits and their morphology was shown. This work was carried out by testing a turbine injector during several hours on a test bench reproducing the working conditions of medium power industrial gas turbine. Different physico-chemical characteristics of common turbine fuels have been tested in an inert atmosphere. The characterization of the deposits (obtained with an electronic microscope), shows their morphology, as well as their elementary composition.
For different fuels and various operating conditions, this work allows also to compare different types of materials used in the construction of gas turbines.
Coke Removal in Fuel-Cooled Thermal Management Systems
Authors: Huang He , Spadaccini Louis J. 
Published: July 2014

The extent to which the benefits of hydrocarbon fuel cooling technology can be realized depends on our ability to manage coke deposits. The coke deposits, which may form in heat exchangers, reactors and on inside surfaces of fuel system components, degrade heat transfer, catalyst activity, and fuel flow characteristics and can lead to system failure. Therefore, in situ regeneration of fouled surfaces was investigated as a practical approach for reducing the impact of coke formation on aircraft thermal management systems.
Thermogravimetric analysis (TGA) was used to evaluate various surface regeneration techniques (such as carbon burnoff in air or oxygen and carbon gasification using CO2 or steam) and to compile a database for kinetics analysis. The most practical technique for in situ surface regeneration of heat exchangers and reactors is the carbon burnoff method. Although the burnoff method is simple and cost-effective, care must be taken to control strong exothermic reactions. For this reason, a kinetics model and a computer simulation have been developed to guide the selection of the key operating variables (i.e., temperature, pressure, and time) for the in situ regeneration method. A surface regeneration simulator was constructed and used to assess the effectiveness of the in situ regeneration techniques and validate the kinetics model. Use of the computer simulation tool in a real application to specify the conditions for removing coke deposits from a fouled heat-exchanger/reactor panel from a scramjet test engine is discussed in the paper.
Tempest Dual Fuel DLE Development and Commercial Operating Experience and Ultra Low NOx Gas Operation
Authors: Cramb D. J. , McMillan R. 
Published: July 2014

Following on from the experience gained on the Typhoon generator set, ALSTOM Power’s generic dual fuel Dry Low Emissions (DLE) combustion system has been successfully developed for operation on the Tempest generator set. The first engine fitted with the full DLE dual fuel system entered service in October 2000.
NOx emissions levels of less than 30vppm at 15% O2 have been demonstrated on distillate fuel. Low levels of combustion dynamics and pilot burner tip temperatures have been demonstarted on both fuels as well as gas fuel emission levels remaining less than 20vppm at 15% O2, the same as the gas only DLE version.
This paper describes the development of the dual fuel DLE system on the Tempest at ALSTOM’s test facilities in Lincoln, England as well as the commercial operating experience gained to date on both the full dual fuel DLE and liquid standby DLE systems. The commercial operating experience will cover areas such as operating concept, liquid starting reliability, and site issues encountered.
The lead Tempest gas only DLE units have successfully completed 22000 hours operation without any issues and will be discussed in the paper.
Steam–Gas Condensing Turbine System for Power and Heat Generation
Authors: Chodkiewicz Ryszard , Porochnicki Jerzy , Kaczan Bazyli 
Published: July 2014

This study deals with new internal combustion turbine power systems in which a steam-gas mixture is the working medium. Heat is delivered to the system by injecting gaseous fuel and steam into the combustion chamber. Unlike in STIG systems, the fluid expansion in the turbine is much deeper (much below the atmospheric pressure) and the exhaust gas is cooled in a heat exchanger-condenser in such a manner that a significant amount of water can be recovered. The non-condensing gases (CO2 + N2 + rest of O2) from the exhaust fluid are compressed, after additional cooling, and discharged into the atmosphere.
If a cheap or waste fuel is available, the steam to be injected into the combustor can be produced in a waste fuel-burning boiler or in conventional coal boiler. In this case the heat exchanger between the turbine and condenser can deliver significant amounts of useful (process or district) heat or / and preheated feedwater for the boiler.
The efficiency analysis of this new energy system shows a growth by more than 10 percent points in comparison with the conventional STIG engine, at the same pressure ratio and turbine inlet temperature.
The Impact of Thermodynamic Properties of Air-Water Vapor Mixtures on Design of Evaporative Gas Turbine Cycles
Authors: Dalili Farnosh , Andrén Martin , Yan Jinyue , Westermark Mats 
Published: July 2014

Reliable thermodynamic property data for air-water vapor mixtures are lacking for the design of evaporative gas turbine cycles (EvGT). Due to high working pressures and temperatures of gas turbines, considerable error would occur when applying the ideal models instead of the real gas mixture models.
This paper presents an extensive literature study regarding models for computing thermodynamic property data of gas mixtures. The Hyland and Wexler model is found to be the best available despite the limited temperature range. However, experimental data are needed to verify the extrapolation.
Furthermore, this paper evaluates the impact of thermodynamic properties of air-water vapor mixtures on the design of EvGT cycles. A suggested EvGT configuration, with results based on ideal gas mixture model and steam tables, is selected as a reference. The real properties of the working fluid mixture are recalculated by the means of the Hyland and Wexler model and applied in the cycle calculation. The results based on real data are compared to those based on ideal.
The results show that the real gas model predicts higher saturation humidity at a given temperature. The higher volatility of water improves the humidification performance. In the case studied here, the flue gas temperature is lowered by about 3°C and the cycle efficiency is improved only marginally. The real gas model predicts higher heat duty for superheating of moist air by about 10 percent, or 2 MW.
Finally, it can be concluded that thermodynamic property data mainly affect component sizing, especially the humid air superheater and to some extent the boiler.
Design Study of Part Flow Evaporative Gas Turbine Cycles: Performance and Equipment Sizing: Part 1 — Aeroderivative Core
Authors: Ågren Niklas D. , Westermark Mats O. J. 
Published: July 2014

The evaporative gas turbine cycle is a new high efficiency power cycle that has reached the pilot testing stage. This paper presents calculation results of a new humidification strategy based on part flow humidification. This strategy involves using only a fraction of the compressed air for humidification. Thermodynamically, it can be shown that not all the air needs to be passed through the humidification system to attain the intrinsic good flue gas heat recovery of an EvGT cycle. The system presented also includes live steam production and superheating by heat from the hottest flue gas region. The humidifier only uses the lower temperature levels flue gas heat, where it is best suited. The analyzed system is based on data for the aeroderivative Rolls Royce Trent as a gas turbine core. Part 2 of this 2-part paper presents the results based on data for the industrial gas turbine ABB GTX100.
Simulation results include electric efficiency and other process datas as functions of degree of part flow. A detailed model of the humidifier is also used and described, which produces sizing results both for column height and diameter.
Full flow humidification generates an electric efficiency of 51.5% (simple cycle 41%). The efficiency increases when the humidification air flow is reduced, to reach a maximum of 52.9% when air flow to the humidification amounts to around 12% of the intake air to the compressor. At the same time, total heat exchanger area is reduced by 50% and humidifier volume by 36% compared to full flow humidification. This calls for a recommendation not to use all the compressed air for humidification.