scholarly journals DESIGN AND DEVELOPMENT OF A 70 N THRUST CLASS TURBOJET ENGINE

2004 ◽  
Vol 3 (1) ◽  
Author(s):  
P. E. Trazzi
Keyword(s):  
Experimental Data ◽  
Combustion Chamber ◽  
Gas Turbines ◽  
Special Design ◽  
Design And Development ◽  
Axial Turbine ◽  
Jet Engine ◽  
Radial Compressor ◽  
Final Configuration ◽  
Turbojet Engine

Small turbojet engines are being used for propulsion of radio-controlled model airplanes. The design and development of the model 505 small jet engine are reviewed. Small size gas turbines present special design and construction difficulties, some of which are addressed; design choices leading to the final configuration are discussed. Aero-thermodynamic aspects are covered along with experimental data when available. The unit is comprised of a radial compressor, an annular combustion chamber, and an axial turbine plus accessories; details on these components and on production aspects are presented.

scholarly journals DESIGN AND DEVELOPMENT OF A 70 N THRUST CLASS TURBOJET ENGINE

2004 ◽  
Vol 3 (1) ◽  
pp. 09 ◽  
Author(s):  
P. E. Trazzi
Keyword(s):  
Experimental Data ◽  
Combustion Chamber ◽  
Gas Turbines ◽  
Special Design ◽  
Design And Development ◽  
Axial Turbine ◽  
Radial Compressor ◽  
Final Configuration ◽  
Turbojet Engine

Small turbojet engines are being used for propulsion of radio-controlled model airplanes. The design and development of the model 505 small jet engine are reviewed. Small size gas turbines present special design and construction difficulties, some of which are addressed; design choices leading to the final configuration are discussed. Aero-thermodynamic aspects are covered along with experimental data when available. The unit is comprised of a radial compressor, an annular combustion chamber, and an axial turbine plus accessories; details on these components and on production aspects are presented.

Design Analysis of a Micro Gas Turbine Combustion Chamber Burning Natural Gas

2012 ◽  
Author(s):  
André Perpignan V. de Campos ◽  
Fernando L. Sacomano Filho ◽  
Guenther C. Krieger Filho
Keyword(s):  
Experimental Data ◽  
Natural Gas ◽  
Combustion Chamber ◽  
Gas Turbines ◽  
Low Cost ◽  
Mixture Fraction ◽  
Combustion Model ◽  
Inlet Temperature ◽  
Gas Combustion ◽  
Micro Turbine

Gas turbines are reliable energy conversion systems since they are able to operate with variable fuels and independently from seasonal natural changes. Within that reality, micro gas turbines have been increasing the importance of its usage on the onsite generation. Comparatively, less research has been done, leaving more room for improvements in this class of gas turbines. Focusing on the study of a flexible micro turbine set, this work is part of the development of a low cost electric generation micro turbine, which is capable of burning natural gas, LPG and ethanol. It is composed of an originally automotive turbocompressor, a combustion chamber specifically designed for this application, as well as a single stage axial power turbine. The combustion chamber is a reversed flow type and has a swirl stabilized combustor. This paper is dedicated to the diagnosis of the natural gas combustion in this chamber using computational fluid dynamics techniques compared to measured experimental data of temperature inside the combustion chamber. The study emphasizes the near inner wall temperature, turbine inlet temperature and dilution holes effectiveness. The calculation was conducted with the Reynolds Stress turbulence model coupled with the conventional β-PDF equilibrium along with mixture fraction transport combustion model. Thermal radiation was also considered. Reasonable agreement between experimental data and computational simulations was achieved, providing confidence on the phenomena observed on the simulations, which enabled the design improvement suggestions and analysis included in this work.

CFD Simulation of a Microturbine Annular Combustion Chamber Fuelled With Methane and Biomass Pyrolysis Syngas: Preliminary Results

2009 ◽  
Author(s):  
Francesco Fantozzi ◽  
Paolo Laranci ◽  
Michele Bianchi ◽  
Andrea De Pascale ◽  
Michele Pinelli ◽  
...  
Keyword(s):  
Experimental Data ◽  
Natural Gas ◽  
Combustion Chamber ◽  
Gas Turbines ◽  
Cfd Simulation ◽  
Combustion Process ◽  
Calorific Value ◽  
Methane Combustion ◽  
Pollutant Emissions ◽  
Preliminary Results

Micro gas turbines could be profitably used, for distributed energy production, also exploiting low calorific value biomass-derived fuels, obtained by means of integrated pyrolysis and/or gasification processes. These synthesis gases show significant differences with respect to natural gas (in terms of composition, low calorific value, hydrogen content, tar and particulate matter content) that may turn into ignition problems, combustion instabilities, difficulties in emission control and fouling. CFD simulation of the combustion chamber is a key instrument to identify main criticalities arising when using these gases, in order to modify existing geometries and to develop new generation combustion chambers for use with low calorific value gases. This paper describes the numerical activity carried out to analyze the combustion process occurring inside an existing microturbine annular combustor. A CFD study of the combustion process performed with different computational codes is introduced and some preliminary results are reported in the paper. A comparison of results obtained with the different codes is provided, for the reference case of methane combustion. A first evaluation of the pollutant emissions and a comparison with the available experimental data is also provided in the paper, showing in particular a good matching of experimental data on NOx emissions at different load conditions. Moreover, the carried out investigation concerns the case of operation with a syngas fuel derived from pyrolysis of biomass and finally the case of syngas and natural gas co-firing. This combustion condition is simulated with a simple reduced chemical kinetic scheme, in order to assess only the key issues rising with this fuel in comparison with the case of methane combustion. The analysis shows that in case of syngas operation the combustor internal temperature hot spots are reduced and the primary zone flame tends to stabilize closer to the injector, with possible implications on the emission release.

DETERMINATION OF THE TYPE OF A SINGLE-USE GRENADE LAUNCHER BASED ON ITS COMPOSITE PARTS AND FRAGMENTS OF REACTIVE GRENADE FOUND AT THE PLACE OF ACCIDENT

2017 ◽  
Vol 17 ◽  
pp. 245-252
Author(s):  
V. V. Somov
Keyword(s):  
Combustion Chamber ◽  
Structural Features ◽  
Outlet Section ◽  
Technical Expertise ◽  
Jet Engine ◽  
Size Ofthe ◽  
Single Use ◽  
Nozzle Block ◽  
Considerable Damage

In carrying out an investigation into the explosion, among others, the investigative version of the use of a single-use reactive grenade launcher is being considered. The most common for criminal explosions are applied grenade launchers RPG-18, RPG-22, RPG-26. Their use is due to a number of such properties as small size and weight, which makes it possible to transfer them covertly, the range of the shot significantly exceeding the range of the hand grenade throw, the high detonating effect of the rocket grenade explosion. The single-use rocket launchers are generally of the same design. Their differences are in the features of the components construction and dimensional characteristics, which are given in the article. On the basis of expert practice, details ofgrenade launchers that remain at the site of the explosion and have the least damage are determined. These details are the objects of investigation of the explosion technical expertise. These objects include launchers of grenade launchers and rocket parts ofjet grenades. The design features of the launchers, their dimensional characteristics and marking symbols make it possible to determine their belonging to a specific type of jet grenade launchers. Missile parts of jet grenades differ in the form of the combustion chamber of the jet engine, nozzle, in the size ofthe outlet section of the nozzle, in the form and size of the stabilizerfeathers. To determine the belonging of the rocket part of the grenade to a specific type ofjet grenade launcher, it’s necessary to establish a set of structural features and dimensional characteristics. At considerable damage of the combustion chamber of the jet engine, as a rule, the nozzle block remains intact that allows to define diameter of critical section of a nozzle, and on it to establish type of the used single-use grenade launcher.

Numerical investigation of non-uniform flow in twin-silo combustors and impact on axial turbine stage performance

2021 ◽  
pp. 095765092199394
Author(s):  
Hafiz M Hassan ◽  
Adeel Javed ◽  
Asif H Khoja ◽  
Majid Ali ◽  
Muhammad B Sajid
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Internal Flow ◽  
Large Temperature ◽  
Clear Understanding ◽  
Gas Temperature ◽  
Turbine Stage ◽  
Flow Angle ◽  
Axial Turbine ◽  
Stage Performance

A clear understanding of the flow characteristics in the older generation of industrial gas turbines operating with silo combustors is important for potential upgrades. Non-uniformities in the form of circumferential and radial variations in internal flow properties can have a significant impact on the gas turbine stage performance and durability. This paper presents a comprehensive study of the underlying internal flow features involved in the advent of non-uniformities from twin-silo combustors and their propagation through a single axial turbine stage of the Siemens v94.2 industrial gas turbine. Results indicate the formation of strong vortical structures alongside large temperature, pressure, velocity, and flow angle deviations that are mostly located in the top and bottom sections of the turbine stage caused by the excessive flow turning in the upstream tandem silo combustors. A favorable validation of the simulated exhaust gas temperature (EGT) profile is also achieved via comparison with the measured data. A drop in isentropic efficiency and power output equivalent to 2.28% points and 2.1 MW, respectively is observed at baseload compared to an ideal straight hot gas path reference case. Furthermore, the analysis of internal flow topography identifies the underperforming turbine blading due to the upstream non-uniformities. The findings not only have implications for the turbine aerothermodynamic design, but also the combustor layout from a repowering perspective.

Transformation of an Aviation Turboshaft Engine Into a Experimental Jet Engine for Laboratory Testing Unstable Radial Compressor Work

2014 ◽  
Author(s):  
Marián Hocko ◽  
Jiri Polansky
Keyword(s):  
Gas Turbine ◽  
Experimental Testing ◽  
Thermodynamic Characteristics ◽  
Power Generator ◽  
Jet Engine ◽  
Radial Compressor ◽  
Laboratory Device ◽  
Research And Education ◽  
Turboshaft Engine ◽  
Electronic Elements

The article deals with the use of a small aviation turboshaft engine for laboratory purposes. This study describes its transformation into an experimental device for research and education. Various constructional, technological and controlling modifications and settings of the gas turbine test stand were carried out and tested on a stationary configuration. The stationary system can be used as a small backup power generator or as a drive unit for a compressor, pump, etc. New control systems, electronic elements and methods of measuring rotations, pressure and temperature are tested for educational and research purposes. The study includes a schematic description of modelling measurements and subsequent numerical evaluation of the thermodynamic characteristics of the cycle in an experimental gas turbine. The laboratory device presented here is, thanks to technological, material and thermodynamic research, suitable for educating and testing the knowledge of future aviation and mechanical engineers. The content of the article is a description of the use of transformed small turboshaft engine into small jet engine by means of experimental testing of unstable work of the radial compressor under laboratory conditions.

Development and Validation of a Three-Dimensional Multiphase Flow CFD Analysis for Journal Bearings in Steam and Heavy Duty Gas Turbines

2012 ◽  
Author(s):  
Stephan Uhkoetter ◽  
Stefan aus der Wiesche ◽  
Michael Kursch ◽  
Christian Beck
Keyword(s):  
Experimental Data ◽  
Multiphase Flow ◽  
Gas Turbines ◽  
High Speed ◽  
Three Dimensional ◽  
Air Entrainment ◽  
Journal Bearings ◽  
Heavy Duty ◽  
Present Contribution ◽  
Two Phase

The traditional method for hydrodynamic journal bearing analysis usually applies the lubrication theory based on the Reynolds equation and suitable empirical modifications to cover turbulence, heat transfer, and cavitation. In cases of complex bearing geometries for steam and heavy-duty gas turbines this approach has its obvious restrictions in regard to detail flow recirculation, mixing, mass balance, and filling level phenomena. These limitations could be circumvented by applying a computational fluid dynamics (CFD) approach resting closer to the fundamental physical laws. The present contribution reports about the state of the art of such a fully three-dimensional multiphase-flow CFD approach including cavitation and air entrainment for high-speed turbo-machinery journal bearings. It has been developed and validated using experimental data. Due to the high ambient shear rates in bearings, the multiphase-flow model for journal bearings requires substantial modifications in comparison to common two-phase flow simulations. Based on experimental data, it is found, that particular cavitation phenomena are essential for the understanding of steam and heavy-duty type gas turbine journal bearings.

Practical Bypass Mixing Systems for Fan Jet Aero Engines

1966 ◽  
Vol 17 (2) ◽  
pp. 141-160 ◽  
Author(s):  
T. H. Frost
Keyword(s):  
Gas Turbines ◽  
Minimum Weight ◽  
Jet Engines ◽  
Metal Interface ◽  
Combustion Chambers ◽  
Propulsion Systems ◽  
Jet Engine ◽  
Aero Engines ◽  
Corrugated Metal ◽  
Constant Static Pressure

SummaryMixing systems have many applications in gas turbines and aircraft jet propulsion, e.g. mixing zones in combustion chambers, ejectors for jet lift thrust augmentors and supersonic propulsion systems. A further application similar to that of combustion chamber mixing is that of mixing the cold and hot exhausts of a bypass jet engine. These are both characterised by mixing at constant static pressure and approximately constant total pressure as opposed to the more general case of unequal pressures in ejector systems (Fig. 1).The exhaust mixing process as used in Rolls-Royce bypass jet engines, e.g. Spey and Conway, enables the potential of the bypass principle, in terms of minimum weight and fuel consumption, to be exploited by a simple practical device.This is achieved by mixing the two streams in a common duct of fairly short dimensions with a corrugated metal interface on the inlet side. The consideration of these practical systems forms the main topic of this paper.

scholarly journals Parametric diagnostics of the condition of a dual-flow turbojet engine using neural network simulation of the operating process

2018 ◽  
Vol 224 ◽  
pp. 02057
Author(s):  
Anas S. Gishvarov ◽  
Julien Celestin Raherinjatovo
Keyword(s):  
Neural Network ◽  
High Pressure ◽  
Combustion Chamber ◽  
Early Stage ◽  
Low Pressure ◽  
Similarity Criteria ◽  
Ann Model ◽  
Turbojet Engine ◽  
Operating Process ◽  
Pressure Compressor

The article presents a method of parametric diagnostics of the condition of a dual-flow turbojet engine (DFTE). The method is based on the identification (determination) of the condition of the DFTE components (the compressor, combustion chamber, turbine) with application of a mathematical model of the operating process which is presented as an artificial neural network (ANN) model. This model describes the relation between the monitored parameters of the DFTE (the air temperatures (Tlpc*, Thpc*) beyond the low pressure compressor (LPC) and the high pressure compressor (HPC), the pressure beyond the LPC (Plpc), the fuel consumption rate (Gf), the gas temperatures (Thpt*, Tlpt*) beyond the high pressure turbine (HPT) and the low pressure turbine (LPT)) and the parameters of the condition of its components (the efficiencies of the LPC and the HPC (ηlpc*, ηhpc*), the stagnation pressure recovery factor in the combustion chamber (σcc), the efficiencies of the HPT and the LPT (ηhpt*, ηlpt*)). The parameters of the condition of the engine components (ηlpc*, ηhpc*, σcc, ηhpt*, ηlpt*) are the similarity criteria (integral criteria) which enable to identify the condition of the DFTE components to a high degree of reliability. Such analysis enables to detect defects at an early stage, even if the values of the monitored parameters (Тlpc*, Тhpc*, Plpc, Gf, Тhpt*, Тlpt*) are within the permissible limits. We provide the sequence for development of the ANN model and the results of its performance study during the parametric diagnostics of the condition of the DFTE.

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