Recursive least squares for online dynamic identification on gas turbine engines

Online identification for a gas turbine engine is vital for health monitoring and control decisions because the engine electronic control system uses the identified model to analyze the performance for optimization of fuel consumption, a response to the pilot command, as well as engine life protection. Since a gas turbine engine is a complex system and operating at variant working conditions, it behaves nonlinearly through different power transition levels and at different operating points. An adaptive approach is required to capture the dynamics of its performance

Discretized Miller approach to assess effects on boundary layer ingestion induced distortion

The performance of propulsion configurations with boundary layer ingestion (BLI) is affected to a large extent by the level of distortion in the inlet flow field. Through flow methods and parallel compressor have been used in the past to calculate the effects of this aerodynamic integration issue on the fan performance; however high-fidelity through flow methods are computationally expensive, which limits their use at preliminary design stage. On the other hand, parallel compressor has been developed to assess only circumferential distortion. This paper introduces a discretized semi-empirical performance method, which uses empirical correlations for blade and performance calculations. This tool discretizes the inlet region in radial and circumferential directions enabling the assessment of deterioration in fan performance caused by the combined effect of both distortion patterns. This paper initially studies the accuracy and suitability of the semi-empirical discretized method by comparing its predictions with CFD and experimental data for a baseline case working under distorted and undistorted conditions. Then a test case is examined, which corresponds to the propulsor fan of a distributed propulsion system with BLI. The results obtained from the validation study show a good agreement with the experimental and CFD results under design point conditions

Integration and expression of Bluetongue VP2 gene in somatic embryos of peanut through particle bombardment method

After pre-culture and treatment of osmosis, zygotic embryos of peanut (Arachis hypogaea L.) were transformed via particle bombardment with a plasmid containing a Bluetongue VP2 gene (BTVP2) comprising neutralizing epitopes. Selection for Kanamycin resistant calluses and somatic embryos was initiated at 12th day post-bombardment on medium containing 25 mg/L Kanamycin. Under continuous selection, 12.38 Kanamycin resistant plantlets were regenerated from bombarded somatic embryos. The presence and integration of BTVP2 DNA in regenerated Kanamycin resistant plants were confirmed by southern hybridization assay using non-radioactive Digoxiginin BTVP2 probe. β-Glucuronidase (GUS) enzyme activity was detected in transgenic somatic embryos but not from control, non-transformed embryos. The expression of the BTVP2 protein was confirmed through RT-PCR (reverse transcription polymerase chain reaction) using the RNA isolated from the transgenic callus employing BTVP2-specific primers. The production of transgenic peanut was mainly focused on evaluating a newly improved somatic embryogenesis regeneration system as well as the gene transfer method and to produce the Bluetongue outer coat protein that comprises the neutralizing epitopes. © 2005 Elsevier Ltd. All rights reserved

Aero engine compressor fouling effects for short- and long-haul missions

The impact of compressor fouling on civil aero engines unlike the industrial stationary application has not been widely investigated or available in open literature. There are questions about the impact of fouling for short- and long-haul missions comparatively, given their unique operational requirements and market. The aim of this study is to quantify the effects of different levels of fouling degradation on the fan, for two different aircraft with different two-spool engine models for their respective typical missions. Firstly, the study shows the increase in turbine entry temperature for both aircraft engines, to maintain the same level of thrust as their clean condition. The highest penalty observed is during take-off and climb, when the thrust setting is the highest. Despite take-off and climb segment being a larger proportion in the short-haul mission compared to the long-haul mission, the percentage increase in fuel burn due to fouling are similar, except in the worst case fouling level were the former is higher by 0.8% points. In addition to this, for all the cases, the additional fuel burn due to fouling and its cost is shown to be small. Likewise, the increase in turbine entry temperature for both missions at take-off are similar, except in the worst case fouling level for the short-haul mission were the turbine entry temperature is 7 K higher than the corresponding long-haul mission for the same level of degradation. The study infers that the penalty due to rise in temperature is of more concern than the additional fuel burn. Hence the blade technology (cooling and material) and engine thrust rating are key factors in determining the extent to which blade fouling would affect aero engine performance in short- and long-haul missions

Techno economic and environmental assessment of Flettner rotors for marine propulsion

Wind energy is a mature renewable energy source that offers significant potential for near-term (2020) and long-term (2050) greenhouse gas (GHG) emissions reductions. Similar to all sectors of the transportation industry, the marine industry is also focused towards reduction of environmental emissions. A direct consequence of this being is a renewed interest in utilising wind as supplementary energy source for propulsion on cargo/merchant ships. This research utilises a techno economic and environmental analysis approach to assess the possibility and benefits of harnessing wind energy, with an aim to establish the potential role of wind energy in reducing GHG emissions during conventional operation of marine vessels. The employed approach enables consistent assessment of different competing traditional propulsion systems when operated in conjunction with a novel environmental friendly technology, in this instance being the Flettner rotor technology. The assessment specifically focuses on quantifying the potential and relative reduction in fuel consumption and pollutant emissions that may be accrued while operating on typical Sea Lines of Communication. The results obtained indicate that the implementation of Flettner towers on commercial vessels could result in potential savings of up to 20% in terms of fuel consumption, and similar reductions in environmental emissions

Development of Randomly Amplified Polymorphic DNA Based SCAR Marker for Identification of Ipomoea mauritiana Jacq (Convolvulaceae)

Vidari is an Ayurvedic herbal drug used as aphrodisiac, galactagogue and is also used in the preparation of Chyavanaprash. Tubers of Ipomoea mauritiana Jacq. (Convolvulaceae), Pueraria tuberosa (Roxb. ex Willd.) DC (Fabaceae), Adenia hondala (Gaertn.) de Wilde (Passifloraceae) and pith of Cycas circinalis L. (Cycadaceae) are all traded in the name of Vidari, creating issues of botanical authenticity of the Ayurvedic raw drug. DNA-based markers have been developed to distinguish I. mauritiana from the other Vidari candidates. A putative 600-bp polymorphic sequence, specific to I. mauritiana was identified using randomly amplified polymorphic DNA (RAPD) technique. Furthermore, sequence characterized amplified region (SCAR) primers (IM1F and IM1R) were designed from the unique RAPD amplicon. The SCAR primers produced a specific 323-bp amplicon in authentic I. mauritiana and not in the allied species

Locating Legal Certainty in Patent Licensing

This open access book presents global perspectives and developments within the information and communication technology (ICT) sector, and discusses the bearing they have on policy initiatives that are relevant to the larger digital technology and communications industry. Drawing on key developments in India, the USA, UK, EU, and China, it explores whether key jurisdictions need to adopt a different legal and policy approach to address the unique concerns that have emerged within the technology-intensive industries. The book also examines the latest law and policy debates surrounding patents and competition in these regions. Initiating a multi-faceted discussion, the book enables readers to gain a comprehensive understanding of complex legal and policy issues that are beginning to emerge around the globe

Complications and Quandaries in the ICT Sector: Standard Essential Patents and Competition Issues

With technology standards becoming increasingly common, particularly in the information and communications technology (ICT) sector, the complexities and contradictions at the interface of intellectual property law and competition law have emerged strongly. This book talks about how the regulatory agencies and courts in the United States, European Union and India are dealing with the rising allegations of anti-competitive behaviour by standard essential patent (SEP) holders. It also discusses the role of standards setting organizations / standards developing organizations (SSO/SDO) and the various players involved in implementing the standards that influence practices and internal dynamics in the ICT sector. This book includes discussions on fair, reasonable and non-discriminatory (FRAND) licensing terms and the complexities that arise when both licensors and licensees of SEPs differ on what they mean by “fair”, “reasonable” and “non-discriminatory” terms. It also addresses topics such as the appropriate royalty base, calculation of FRAND rates and concerns related to FRAND commitments and the role of Federal Trade Commission (FTC) in collaborative standard setting process. This book provides a wide range of valuable information and is a useful tool for graduate students, academics and researchers

Installed performance assessment of an array of distributed propulsors ingesting boundary layer flow

Conventional propulsion systems are typically represented as uninstalled system to suit the simple separation between airframe and engine in a podded configuration. However, boundary layer ingesting systems are inherently integrated, and require a different perspective for performance analysis. Simulations of boundary layer ingesting propulsions systems must represent the change in inlet flow characteristics which result from different local flow conditions. In addition, a suitable accounting system is required to split the airframe forces from the propulsion system forces. The research assesses the performance of a conceptual vehicle which applies a boundary layer ingesting propulsion system - NASA's N3-X blended wing body aircraft - as a case study. The performance of the aircraft's distributed propulsor array is assessed using a performance method which accounts for installation terms resulting from the boundary layer ingesting nature of the system. A `thrust split' option is considered which splits the source of thrust between the aircraft's main turbojet engines and the distributed propulsor array. An optimum thrust split for a specific fuel consumption at design point is found to occur for a thrust split value of 94.1%. In comparison, the optimum thrust split with respect to fuel consumption for the design 7500 nmi mission is found to be 93.6%, leading to a 1.5% fuel saving for the configuration considered