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Electrostatic monitoring technology is a useful tool for monitoring and detecting component faults and degradation, which is necessary for engine health management. This paper aims to carry out online monitoring experiments of turbo-shaft engine to contribute to the practical application of electrostatic sensor in aero-engine.

Combined with the time and frequency domain methods of signal processing, the authors analyze the electrostatic signal from the short timescale and the long timescale.

The short timescale analysis verifies that electrostatic sensor is sensitive to the additional increased charged particles caused by abnormal conditions, which makes this technology to monitor typical failures in aero-engine gas path. The long scale analysis verifies the electrostatic sensor has the ability to monitor the degradation of the engine gas path performance, and water washing has a great impact on the electrostatic signal. The spectrum of the electrostatic signal contains not only the motion information of the charged particles but also the rotating speed information of the free turbine.

The findings in this article prove the effectiveness of electrostatic monitoring and contribute to the application of this technology to aero-engine.

The research in this paper would be the foundation to achieve the application of the technology in aero-engine.

The purpose of this paper is to formulate a structured approach to design an annular diffusion flame combustion chamber for use in the development of a 1,400 kW range aero turbo shaft engine. The purpose is extended to perform numerical combustion modeling by solving transient Favre Averaged Navier Stokes equations using realizable two equation k-e turbulence model and Discrete Ordinate radiation model. The presumed shape β-Probability Density Function (β-PDF) is used for turbulence chemistry interaction. The experiments are conducted on the real engine to validate the combustion chamber performance.

The combustor geometry is designed using the reference area method and semi-empirical correlations. The three dimensional combustor model is made using a commercial software. The numerical modeling of the combustion process is performed by following Eulerian approach. The functional testing of combustor was conducted to evaluate the performance.

The results obtained by the numerical modeling provide a detailed understanding of the combustor internal flow dynamics. The transient flame structures and streamline plots are presented. The velocity profiles obtained at different locations along the combustor by numerical modeling mostly go in-line with the previously published research works. The combustor exit temperature obtained by numerical modeling and experiment are found to be within the acceptable limit. These results form the basis of understanding the design procedure and opens-up avenues for further developments.

Internal flow and combustion dynamics obtained from numerical simulation are not experimented owing to non-availability of adequate research facilities.

This study contributes toward the understanding of basic procedures and firsthand experience in the design aspects of combustors for aero-engine applications. This work also highlights one of the efficient, faster and economical aero gas turbine annular diffusion flame combustion chamber design and development.

The main novelty in this work is the incorporation of scoops in the dilution zone of the numerical model of combustion chamber to augment the effectiveness of cooling of combustion products to obtain the desired combustor exit temperature. The use of polyhedral cells for computational domain discretization in combustion modeling for aero engine application helps in achieving faster convergence and reliable predictions. The methodology and procedures presented in this work provide a basic understanding of the design aspects to the beginners working in the gas turbine combustors particularly meant for turbo shaft engines applications.

This study aims to ascertain the greenest helicopters by modeling joint parameters to make sense of induced emissions effects of helicopters allocated to various categories.

Emission indexes of helicopters construct the pillars of the methodology under use. Three different parameters are derived from emission indices: the index showing grams of pollutants that an engine produces per kWh; the index comparing of pollutant mass depending on the energy content of the fuel; and the index expressing the presence of the unreacted hydrocarbon (unburned) released into the atmosphere as a result of the combustion reaction.

Various helicopters have been designated as sensitive and insensitive to the environment under various conditions and in different categories. Details are in the conclusions section.

This study includes methods that can be used to select environmentally sensitive helicopters of various categories according to specific pollutants and their combustion efficiency.

The originality of the work lies in the determination of the most sensitive and insensitive to the environment by using true flight data of helicopters operating in various categories during different flight phases. In addition, this paper with an approach to identifying green helicopters has the capability to support studies on regulations for helicopters in some countries by policymakers.

The purpose of this paper is to explore some of the challenges associated with the integration of an LH2-fuelled advanced hybrid-electric distributed propulsion system with the airframe. The airframe chosen as a case study is an ultra-high-capacity blended wing body configuration. It is designed to represent an A-380 class vehicle but in the 2025-2030 timeframe. The distributed propulsion system is a hybrid-electric concept that utilizes high-temperature superconducting technologies. The focus of the study is the application of LH2 as a fuel, with comment being given to kerosene and LCH4.

The study consists of a conceptual design developed through the preliminary design phase and part way into the detailed design phase.

The relationship between passenger capacity and fuel capacity is developed. Some remaining challenges are identified.

The study supports further conceptual design studies and more detailed system studies.

The study contributes to the development of more environmentally benign aviation technologies. The study may assist the development of solutions to the peak oil challenge.

The study explores the integration of a number of complex systems into an advanced airframe to an unusual depth of engineering detail.

Advanced facility for design development and manufacture of gas turbine electronic controls

THE future prospects for collaborative ventures were outlined recently to the Royal Aeronautical Society by Allen Greenwood of BAC who is the President of the European Association of Aerospace Manufacturers (AECMA). It is considered that the only successful course for European Aerospace is to ensure that it meets its own needs, otherwise it will become a junior partner to the American industry. Obviously, it does not make sense for a European government to finance both airlines and manufacturers and then buy the majority of its aircraft from the USA. A similar principle applies in the military field where a country's money is used for the purchase of defence equipment outside the continent.

Raytheon Co were showing their advanced‐design display console known as the plan view display, forming part of the computer display channel equipment as produced for air traffic controllers to cover a 70 mile diameter sector of air space over Boston. On the high‐resolution screen, aircraft information and movements are displayed in clear alphanumeric characters and lines. The area under control is set off by an electronic, dashed sector boundary on the screen, and the display shows airways, intersections, and geographic fixes as well as VHF omnirange stations and airport locations.

With the objective to assess potentially performant hybrid-electric architectures, this paper aims to present an aircraft performance level evaluation, in terms of range and payload, of the synergies between a hybrid-electric energy system configuration and a cryogenic fuel system.

An unmanned aerial vehicle (UAV) is modeled using an aircraft performance tool, modified to take into account the hybrid nature of the system. The fuel and thermal management systems are modeled looking to maximize the synergistic effects. The electrical system is defined in series with the thermal engine and the performance, in terms of weight and efficiency, are tracked as a function of the cooling temperature.

The results show up to a 46 per cent increase in range and up to 7 per cent gain on a payload with a reference hybrid-electric aircraft that uses conventional drop-in JP-8 fuel. The configuration that privileges a reduction in mass of the electric motors by taking advantage of the cryogenic coolant temperature shows the highest benefits. A sensitivity study is also presented showing the dependency on the modeling capabilities.

The synergistic combination of a cryogenic fuel and the additional heat sources of a hybrid-electric system with a tendency to higher electric component efficiency or reduced weight results in a considerable performance increase in terms of both range and payload.

The potential synergies between a cryogenic fuel and the electrical system of a hybrid-electric aircraft seem clear; however, at the present, no detailed performance evaluation at aircraft level that includes the fuel, thermal management and electric systems, has been published.