scholarly journals Экспериментальное определение вибрационных характеристик рабочих лопаток турбин помехоустойчивым цифровым спекл-интерферометром

2021 ◽  
pp. 52-61
Author(s):  
Михаил Романович Ткач ◽  
Юрий Григорьевич Золотой ◽  
Ирина Юрьевна Жук ◽  
Юрий Николаевич Галинкин ◽  
Аркадий Юрьевич Проскурин ◽  
...  
Keyword(s):  
High Efficiency ◽  
Speckle Pattern ◽  
Flaw Detection ◽  
Video Camera ◽  
Speckle Interferometry ◽  
Optical Scheme ◽  
Turbine Engine ◽  
Asymmetric Structures ◽  
Speckle Correlation ◽  
Rotary Platform

The paper notes the wide possibilities and high efficiency of vibration diagnostics of parts and assemblies of power units by the method of electronic speckle interferometry (ESI), shows the feasibility of developing and improving methods for obtaining speckle interferograms of vibrating objects. A patented by the authors' scheme of a digital speckle interferometer (DSI) for determining the dynamic parameters of products is presented. The diffuse reference wave greatly simplifies its alignment, mainly the aligned channels of propagation of interfering beams determine the resistance to mechanical and thermal disturbances, and the separate beam splitter and diffuser make it easy to optimize the optical scheme for the object under study. Speckle interferograms are obtained by speckle correlation methods and a developed method for determining the contrast of the dynamic speckle pattern. It does not impose special requirements on the parameters of the video system, does not require the use of a specialized video camera, and allows, by using a rotary platform, to organize a panoramic view of the oscillatory forms of asymmetric structures. The use of this method in combination with the proposed optical scheme provides an express analysis of products in off-bench conditions. The increased noise immunity of the installation allows the determination of the spectrum of frequencies and vibration modes (SFVM) of samples under free boundary conditions, which is rarely realized in interferometry. The paper presents examples of such speckle interferograms, the expediency of obtaining which is important in the resonance study of the elastic properties of the material and vibration resonance flaw detection. The implemented software and hardware solutions increase the resolution and visibility of the band patterns; facilitate their quantitative interpretation and the extraction of numerical information on the distribution of vibration amplitudes. The area of scientific interests and the specificity of the author's developments have determined the preferential adaptation of the proposed device with a complex of software and methodological developments for vibration testing of gas turbine engine (GTE) blades.

CHARACTERIZING DYNAMIC SPECKLE TIME SERIES WITH THE HURST COEFFICIENT CONCEPT

Fractals ◽  
2004 ◽  
Vol 12 (03) ◽  
pp. 319-329 ◽  
Author(s):  
L. I. PASSONI ◽  
H. RABAL ◽  
C. M. ARIZMENDI
Keyword(s):  
Speckle Pattern ◽  
Time History ◽  
Speckle Interferometry ◽  
Active Materials ◽  
Laser Illumination ◽  
Corn Seed ◽  
Dynamic Speckle ◽  
Hurst Coefficient ◽  
History Of ◽  
Living Tissues

We propose in this work a dynamic speckle descriptor based on a Hurst wavelet estimator. The dynamic speckle or biospeckle is a phenomenon produced by laser illumination of active materials, such as biological tissue or the drying process of paint. Dynamic speckle interferometry is a useful technique for assessing the time evolution of surfaces as also to segment the loci of different activity in living tissues. Considering previous biospeckle characterization based on the autocorrelation function and its relation with the Hurst coefficient, a wavelet-based estimator is proposed as a feature extraction of the dynamic speckle characteristic. Encouraging results of the descriptor performance are obtained via three different experiments: a time history of speckle pattern applied to the drying of painting, segmenting regions in whole field image applied to the viability test of a corn seed and also to the bruising in fruits.

scholarly journals Evaluation of the quality of the shielded metal arc welding process using speckle interferometry

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Felipe Maia Prado ◽  
Daniel José Toffoli ◽  
Sidney Leal Da Silva
Keyword(s):  
Arc Welding ◽  
Speckle Pattern ◽  
Welding Process ◽  
Time History ◽  
Speckle Interferometry ◽  
Shielded Metal Arc Welding ◽  
Metal Arc Welding ◽  
Properties Of Materials ◽  
Arc Welding Process

Speckle, which is a branch of optics that studies the interference pattern caused by the incidence of coherent light in a material’s surface, has some optical techniques and methods that can be successfully applied to determine properties of materials. In this work we used the method called THSP, Time History Speckle Pattern, in samples made of AISI 1020 carbon steel that were submitted to the shielded metal arc welding (SMAW) process, with the objective of identifying (qualitatively) the level of irregularity on its welded surface, by comparing these samples with a default sample, made with the same material. The technique of spekle by reflection was used for data collection. The results showed quantitative diferences between the default welded sample and the other samples, and there are good perspectives that speckle can be applied to determine the quality of the welding process, since the results showed more accuracy than visual inspection.  

The ultra-high efficiency gas turbine engine, UHEGT, Part II: A numerical study on reducing the stator blade surface temperature by indexing fuel injectors and using film cooling

2020 ◽  
pp. 095765092097353
Author(s):  
Seyed M Ghoreyshi ◽  
Meinhard T Schobeiri
Keyword(s):  
Surface Temperature ◽  
Gas Turbine ◽  
Film Cooling ◽  
Total Pressure ◽  
High Efficiency ◽  
Combustion Process ◽  
Blade Surface ◽  
Turbine Engine ◽  
Fuel Injectors ◽  
Stator Blade

In the Ultra-High Efficiency Gas Turbine Engine, UHEGT (introduced in our previous studies) the combustion process is no longer contained in isolation between the compressor and turbine, rather distributed within the axial gaps before each stator row. This technology substantially increases the thermal efficiency of the engine cycle to above 45%, increases power output, and reduces turbine inlet temperature. Since the combustion process is brought into the turbine stages in UHEGT, the stator blades are exposed to high-temperature gases and can be overheated. To address this issue and reduce the temperature on the stator blade surface, two different approaches are investigated in this paper. The first is indexing (clocking) of the fuel injectors (cylindrical tubes extended from hub to shroud), in which the positions of the injectors are adjusted relative to each other and the stator blades. The second is film cooling, in which cooling holes are placed on the blade surface to bring down the temperature via coolant injection. Four configurations are designed and studied via computational fluid dynamics (CFD) to evaluate the effectiveness of the two approaches. Stator blade surface temperature (as the main objective function) along with other performance parameters such as temperature non-uniformity at rotor inlet, total pressure loss over the injectors, and total power production by rotor are evaluated for all configurations. The results show that indexing presents the most promising approach in reducing the stator blade surface temperature while producing the least amount of total pressure loss.

scholarly journals 2MW Class High Efficiency Gas Turbine IM270 for Co-Generation Plants

1996 ◽  
Author(s):  
Hideo Kobayashi ◽  
Shogo Tsugumi ◽  
Yoshio Yonezawa ◽  
Riuzou Imamura
Keyword(s):  
Gas Turbine ◽  
High Efficiency ◽  
Mechanical Design ◽  
Development Program ◽  
Gas Turbine Engine ◽  
Maintenance Cost ◽  
Turbine Engine ◽  
Generation Plant ◽  
Emission Regulation ◽  
Heavy Duty Gas Turbine

IHI is developing a new heavy duty gas turbine engine for 2MW class co-generation plants, which is called IM270. This engine is a simple cycle and single-spool gas turbine engine. Target thermal efficiency is the higher level in the same class engines. A dry low NOx combustion system has been developed to clear the strictest emission regulation in Japan. All parts of the IM270 are designed with long life for low maintenance cost. It is planned that the IM270 will be applied to a dual fluid system, emergency generation plant, machine drive engine and so on, as shown in Fig.1. The development program of IM270 for the co-generation plant is progress. The first prototype engine test has been started. It has been confirmed that the mechanical design and the dry low NOx system are practical. The component tuning test is being executed. On the other hand, the component test is concurrently in progress. The first production engine is being manufactured to execute the endurance test using a co-generation plant at the IHI Kure factory. This paper provides the conceptual design and status of the IM270 basic engine development program.

scholarly journals A Model and State-Space Controllers for an Intercooled, Regenerated (ICR) Gas Turbine Engine

1992 ◽  
Author(s):  
J. W. Watts ◽  
T. E. Dwan ◽  
R. W. Garman
Keyword(s):  
State Space ◽  
Gas Turbine ◽  
High Efficiency ◽  
Linear Quadratic Regulator ◽  
Gas Turbine Engine ◽  
Linear Quadratic ◽  
Turbine Engine ◽  
Simulation Language ◽  
Linear State ◽  
High Level

A two-and-one-half spool gas turbine engine was modeled using the Advanced Computer Simulation Language (ACSL), a high level simulation environment based on FORTRAN. A possible future high efficiency engine for powering naval ships is an intercooled, regenerated (ICR) gas turbine engine and these features were incorporated into the model. Utilizing sophisticated instructions available in ACSL linear state-space models for this engine were obtained. A high level engineering computational language, MATLAB, was employed to exercise these models to obtain optimal feedback controllers characterized by the following methods: (1) state feedback; (2) linear quadratic regulator (LQR) theory; and (3) polygonal search. The methods were compared by examining the transient curves for a fixed off-load, and on-load profile.

Speckle interferometry by using virtual speckle pattern based on Carré algorithm

MAPAN ◽  
2011 ◽  
Vol 26 (4) ◽  
pp. 303-314 ◽  
Author(s):  
Yasuhiko Arai ◽  
Yasunori Tsutsumi ◽  
Marie Kikukawa ◽  
Shunsuke Yokozeki
Keyword(s):  
Speckle Pattern ◽  
Speckle Interferometry

Remote laser speckle interferometry: A speckle pattern formation model

2008 ◽  
Vol 38 (5) ◽  
pp. 477-481 ◽  
Author(s):  
N P Badalyan ◽  
V V Kijko ◽  
V I Kislov ◽  
A B Kozlov
Keyword(s):  
Pattern Formation ◽  
Speckle Pattern ◽  
Speckle Interferometry ◽  
Laser Speckle ◽  
Formation Model

scholarly journals The Use Of Microturbines as an Energy Converter For Motor Transport

2019 ◽  
Vol 8 (10) ◽  
pp. 2700-2703
Keyword(s):  
Fuel Consumption ◽  
High Speed ◽  
Internal Combustion Engines ◽  
High Efficiency ◽  
Mechanical Energy ◽  
Electrical Energy ◽  
Motor Vehicles ◽  
Turbine Engine ◽  
Range Extender ◽  
Traction Motors

At this stage of the development of vehicles with a combined power plant, one of the areas of development is the study of the introduction of a low-power gas turbine engine, the so-called microturbine, as a converter of thermal energy into mechanical. This solution has numerous positive aspects related to its fuel consumption, small dimensions, high efficiency, as well as a number of performance indicators. In this case, the vehicle is also equipped with a high-speed generator with the goal of converting the mechanical energy of the microturbine into electrical energy. This ensures the microturbine operation in a given range on the characteristic of optimal fuel consumption. The article contains an analysis of the use of microturbine generators in vehicles; some constructive solutions are considered as well. An overview of vehicles with microturbine generators and their comparison with traditional internal combustion engines is given. The movement of the vehicle is carried out by one or several traction motors. More than ten developments of motor vehicles using the microturbine as an additional source of energy for vehicles with traction electric drive are already known in the world, including MiTRE (Microturbine Range Extender). Among such vehicles, one can name the Trolza "Ecobus" buses, Delta Hypercar supercar, Isuzu NPR trucks, Mack Truck, Kenworth.

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