Showing papers on "Afterburner published in 2012"

Study on a novel solid oxide fuel cell/gas turbine hybrid cycle system with CO2 capture

Abstract: SUMMARY A novel solid oxide fuel cell (SOFC)/gas turbine (GT) hybrid cycle system with CO2 capture is proposed based on a typical topping cycle SOFC/GT hybrid system. The H2 gas is separated from the outlet mixture gas of SOFC1 anode by employing the advanced ceramic proton membrane technology, and then, it is injected into SOFC2 to continue a new electrochemical reaction. The outlet gas of SOFC1 cathode and the exhaust gas from SOFC2 burn in the afterburner 1. The combustion gas production of the afterburner1 expands in the turbine 1. The outlet gas of SOFC1 anode employs the oxy-fuel combustion mode in the afterburner 2 after H2 gas is separated. Then, the combustion gas production expands in the turbine 2. To ensure that the flue gas temperature does not exceed the maximum allowed turbine inlet temperature, steam is injected into the afterburner 2. The outlet gas of the afterburner 2 contains all the CO2 gas of the system. When the steam is removed by condensation, the CO2 gas can be captured. The steam generated by the waste heat boiler is used to drive a refrigerator and make CO2 gas liquefied at a lower temperature. The performance of the novel quasi-zero CO2 emission SOFC/GT hybrid cycle system is analyzed with a case study. The effects of key parameters, such as CO2 liquefaction temperature, hydrogen separation rate, and the unit oxygen production energy consumption on the new system performance, are investigated. Compared with the other quasi-zero CO2 emission power systems, the new system has the highest efficiency of around 64.13%. The research achievements will provide the valuable reference for further study of quasi-zero CO2 emission power system with high efficiency. Copyright © 2011 John Wiley & Sons, Ltd.

Control method of gas-turbine engine with afterburner, and system used for its implementation

Abstract: FIELD: engines and pumps. ^ SUBSTANCE: control of gas-turbine engine (GTE) with afterburner is performed as per one of three control loops; individual control programme is specified on each loop and corrected as per certain group of sensors the readings of which are the most essential for operation exactly in that mode. ^ EFFECT: invention allows improving operating reliability and safety of GTE with afterburner of airborne vehicle due to reducing the time of augmented and full acceleration of GTE and expansion of safe startup area of afterburner, and providing GTE operation in wide range in optimum modes. ^ 2 cl, 1 dwg

Geometrical variable flame stabilizing device

Abstract: The invention discloses a geometrical variable flame stabilizing device and belongs to the technical field of afterburner flame stabilization of aircraft engines. The geometrical variable flame stabilizing device disclosed by the invention utilizes a V-shape as a basic bluff body structure and consists of a main body part and a transmission power part, wherein the main body part is vertically installed in an afterburner cartridge receiver, the afterburner cartridge receiver comprises a front streamline head part, a blade A with a rotating shaft A, a blade B with a rotating shaft B, a rotating shaft supporting plate and a mounting seat, and the two ends of the streamline head part are fixedly connected between the mounting seat and the rotating shaft supporting plate. The geometrical shape of the flame stabilizing device provided by the invention can be changed to effectively reduce the flow resistance of the flame stabilizing device if necessary, or the flow resistance is increased within a short time to improve the ignition success rate, or the geometrical shape of the flame stabilizing device is adjusted to consistently keep the flame stabilizing device at the optimal combination point of the flame stabilization and flow resistance loss so as to obtain the maximal thrust performance of the afterburner.

GOJETT: A Supersonic Unmanned Aerial Flight System

Abstract: The University of Colorado at Boulder has been researching improvements to small turbojet engines designed for unmanned aerial system for the past three years. The GOJETT (Graduate Organization Jet Engine Technology Team) team continued this work, focusing on designing a supersonic (Mach 1.4) unmanned aerial system to be used as a flight test bed for research such as sonic boom minimization, storm penetration, thrust vectoring, control algorithms, and other system level tests. The current goal, with the addition of an afterburner, a variable area nozzle, and fluidic injection thrust vectoring system, the team seeks to build the world's fastest 50kg UAS in accordance with Federation Aeronautique Internationale guidelines. The current aircraft and propulsion system design details are presented. The vehicle has been through preliminary design review and wind tunnel testing at the US Air Force Academy. Along with ongoing propulsion system test, the team is preparing for integrated vehicle and thrust-vectoring system tests.

Demonstration of an Afterburner and Nozzle in a mini- Turbojet Engine (DANTE)

Abstract: The Busemann Advanced Concepts Lab at the University of Colorado Boulder has been researching improvements to small turbojet engines designed for unmanned aerial vehicles for the past three years. The goal of the DANTE project is to design, fabricate, integrate, and test an afterburner on a mini-turbojet engine and increase the thrust of the engine by at least 50%. The project team is working with a US Microjet AT-450 engine that, without any modifications to the manufacturer’s design, is capable of producing 200 N (45 lbf) of static thrust at sea level. The afterburner design incorporates a variable-area convergent nozzle which allows the engine to operate with a choked nozzle when the afterburner is in operation as well as when the afterburner is off, allowing for the greatest performance from the engine in both modes of operation. The performance of the modified engine was assessed through a series of tests at both the component and the system level. The designs of the afterburner and its components, as well as the test results are presented.

Gas Turbine Engines: Fundamentals

Abstract: The gas turbine engine and its conventional variants (turbojet, turbofan, turboprop, and turboshaft) provide an effective means for thrust and power delivery for a wide number of atmospheric flight applications. In this chapter, the design and performance analysis of gas turbine engines will be introduced, with the turbojet engine as the primary focus (detailed analyses of other gas turbine variants are introduced in subsequent chapters). The principal components of a conventional gas turbine engine are examined in some detail (intake, compressor, combustor, turbine, exhaust nozzle). Other components that are sometimes utilized by turbojet engines (and other variants), such as an afterburner placed between the turbine section and exhaust nozzle, are also discussed.

Numerical simulation on thrust correction of an aero-engine in indoor engine test cell

Abstract: The thrust aerodynamic correction of an aero-engine in an indoor engine test cell is researched under the rating state,the maximum power state and the full afterburner state.The work is based on a 3D computational fluid dynamic(CFD) method with NUMECA software and it includes a preliminary validation about calculation accuracy.The results demonstrate that the flow of air in the indoor engine test cell is predicted successfully,and the thrust correction terms are reasonable and reliable in the trend and range of values.Under high engine mass-flow conditions,Inlet Momentum Drag has significant impact on thrust correction.At the same time,Additive Drag and Suction Drag also affect the thrust correction to some extent.

Method and arrangement for determining enthalpy change of a fuel cell system

Abstract: An object of the invention is an arrangement, which comprises means (125) for measuring temperature in the afterburner (123) or substantially near the afterburner (123) to form afterburner temperature change information, means (127) for determining information on consumed fuel amount in the fuel cells (103) on the basis of the current information, means for determining information on air amount in the afterburner (123), means (133) for determining residual enthalpy change information on the basis of said afterburner temperature change information, said information on air amount in the afterburner, and on the basis of said information on consumed fuel amount in the fuel cells. The means (120) for obtaining at least one of fuel input enthalpy information and fuel input concentration information on the basis of the determined residual enthalpy change information, said means (120) being configured to determine methane content information of the fuel feed (117) by utilizing said obtained at least one of fuel input enthalpy information and fuel input concentration information.

Miniature solid propellant engine

Abstract: FIELD: engines and pumps. ^ SUBSTANCE: proposed engine comprises casing with charge. Igniter with pyro composition enclosed in thin-wall tight envelopment is arranged on grid located nearby charge end face. Pyrocartridge with afterburner tube is arranged in casing cover. Afterburner tube edge is spaced apart from igniter envelopment. Igniter envelopment has cylindrical recess made on the side of afterburner tube and aligned with the latter that feature the following relations of recess height h and diameter D of recess from afterburner tube inner diameter d: denhen2d and 3denDen5d. ^ EFFECT: higher reliability and efficiency. ^ 4 dwg

A cooled afterburner

Abstract: An afterburner 2 with a bypass air flow 4 wherein the afterburner comprises a conical guide or vane 1 which is used to spin air which enters from around the outside of the afterburner. The spun air forms an insulating jacket 6 around the combustion 7 of the fuel in the afterburner. The conical guide or vanes may be movable such that the angle between the afterburner and the bypass air flow may be variable thus altering the amount of air which is received into an engine for different speeds. The angle of the spun air may be between 0 degrees and 45 degrees. The conical guide or vanes may be movable with hydraulics.

Method of using an afterburner to reduce high velocity jet engine noise

Abstract: A system and method of reducing noise caused by jet engines is provided. The method comprises the steps of using the afterburner to heat the exhaust gas flow while simultaneously reducing power to the core engine. Together these two operations reduce the pressure of the exhaust gas in the nozzle area while holding the exhaust gas velocity constant, which maintains engine thrust while decreasing engine noise. The method may be supplemented by altering the location of the afterburner flames to create an inverted exhaust velocity profile, thereby decreasing engine noise even further.

Solid-propellant rocket engine nozzle

Abstract: FIELD: engines and pumps.SUBSTANCE: proposed nozzle comprises case, subsonic and supersonic parts and seal-and-start device with afterburner tube and support. Flat swirler is arranged in said afterburner tube perpendicular to its axis at a distance from outlet cross-section at rigid mounts. Lengthwise axes of the latter are located in planes extending through afterburner tube axis. Flat swirler is provided with one or several bores and lining with low ablation temperature fitted at its front end surface.EFFECT: decreased scatter of internal ballistic parameters at acceleration.3 cl, 1 dwg

A parametric study using two design methodologies for pressure jet and swirl injectors

Abstract: One of the most important subsystems in the air-breathing engines is the atomizers, which break the fuel into many droplets. It is well known that atomization quality has a significant influence on combustion characteristics such as stability limits, efficiency, and pollutant emission. Both jet and swirl injectors are applicable in gas turbine engines. The latter have been widely used for combustion chambers and the former are usually employed for fuel injection in the afterburner part. Since experimental and numerical study of atomizers could be complex and costly, a design methodology of atomizers based on empirical relations is still very advantageous and effective in reducing experimental efforts. We describe the design algorithm for both jet and swirl injectors, for which it is inevitable to use empirical relations. Detailes of the design algorithm are presented to determine the injector dimensions. The final dimensions are also a function of fuel properties and surrounding conditions. For instance, in liquid jet injectors, the type of the inlet and its length to diameter ratio are very important in term of instability aspects. Therefore, the effect of five type of inlets are considered and compared. Loss effects are also taken into account in this study, including loss of energy related to vortices generated due to fluid contraction, loss of energy related to vortices generated due to expansion after contraction and loss of energy due to friction. Using the methodology of design presented here for both types of injectors, the influence of different parameters on atomizer dimensions as well as spray characteristics of both types are finally compared and discussed.

Wake Flow Control on the Afterburner behind Fuel Injection and Flame Holding Strut for Hypersonic Vehicle

Abstract: JAXA’s test model of Pre-Cooled Turbojet Engine, which is called S-engine, for hypersonic vehicle is now under experimental phase. A Series of ground combustion test showed that the combustion efficiency of S-engine’s afterburner was low. To improve the combustion efficiency, breakdown control of Karman vortex sheet behind fuel injection and flame holding strut was proposed. It aims to convert the large scale vortices into smaller scale vortices to enhance the mixing. Several types of struts with zigzag shaped cutouts were investigated in the cold flow field, which simulate the afterburner’s one. The results show that zigzag shaped struts introduced the smaller scale vortices than that of normal strut and induced streamwise vortices in the wake flow.

Rocket power plant with non-sensitive arming and multiple operating modes, and its operating method

Abstract: FIELD: engines and pumps. ^ SUBSTANCE: rocket power plant includes liquid oxidiser and solid fuel in separate compartments, main nozzle, afterburner, liquid oxidiser injectors and air intake supplying the air to afterburner. The main nozzle is located downstream of solid fuel compartment and receives exit gas enriched with fuel after combustion of liquid oxidiser and solid fuel. Afterburner is located downstream of the main nozzle and has the inner part covered with rocket fuel rich in oxidiser. Liquid oxidiser injector located upstream includes the first valve supplying the liquid oxidiser to the end of solid fuel, which is located upstream. Liquid oxidiser injector located downstream includes the second valve acting irrespective of the first valve and supplying the liquid oxidiser before the main nozzle. At operation of the above power plant there mixed are combustion products of liquid oxidiser and solid fuel, which are rich in fuel, and solid rocket fuel rich in oxidiser for acceleration in afterburner, creation of draft and provision of translation movement as hybrid rocket engine. ^ EFFECT: inventions allow increasing the safety of rocket power plant. ^ 9 cl, 15 dwg

Large eddy simulations of separated flow at the casing tongue of an afterburner fuel pump

Abstract: To solve the uncommon cavitation damage problem near the casing tongue of an afterburner fuel pump on a certain type of aero-engine,the unsteady flow field inside the pump at different flow rates was studied by large eddy simulations with the dynamic subgrid-scale stress model.The separated flow characteristics and pressure fluctuations around the casing tongue were analyzed to find the conditions causing the cavitation.The results show unsteady separating eddies near the casing tongue.At full afterburner conditions,with the periodic growth and shedding of the separation eddies,the monitoring pressure fluctuation amplitude at the casing tongue reaches 14%,while the amplitude is only 3% downstream.At low flow conditions,the blocked fuel in the diffuser flows over the casing tongue back to the annular chamber,which triggers serious separation.The shedding of the separated vortex lowers the static pressure at the casing tongue to less than zero with the separation point in accord with the cavitation damage core region.Thus,at full afterburner conditions there is no cavitation near the casing tongue,while at low flow conditions the separated flow induces cavitation and damage.

Control method of jet turbine double-flow engine with afterburner

Abstract: FIELD: machine building. ^ SUBSTANCE: control of jet turbine double-flow engine with afterburner in augmented modes consists in the following: as measured values there used is fuel consumption (GF mcc) characterising the fuel consumption to the main combustion chamber (MCC), rotation frequency (nr) characterising the rotation frequency of low pressure shaft, pressure (pc*) characterising total air pressure after compressor; as control value there used is temperature (tin*) characterising total inlet air temperature of engine and angle (tl) characterising the position of throttle lever (TL). In order to influence the actuating element determining the fuel supply to the afterburner, fuel consumption Gta supplied to afterburner in augmented conditions is used as the value characterising the control signal, and it is determined in compliance with the programme as per the law (GF mcc + Gta) / (Pc*nr) = f(TinCe*, tl). ^ EFFECT: invention allows supporting the required thrust in augmented conditions at deterioration of characteristics of the engine components with operating time. ^ 1 dwg

Analysis of non-reacting and reacting flow inside a jet engine afterburner and parametric studies

Abstract: The objective of the present investigation is to analyse the non-reacting and reacting flow inside a gas turbine engine afterburner. The geometry consists of a diffuser with struts, a V-gutter for flame stabilisation, a combustion chamber and a C-D nozzle. Finite Volume Method-based software is used. Considering the geometrical symmetry of the configuration, a 180° sector is considered for analysis. The turbulence has been modelled using the RNG version of the k-e model and the presumed PDF model is used for reacting flow. The influence of the V-gutter location and variations of the core inlet mass flow rate are examined for the non-reacting flow case. The influence of air-fuel ratio is examined for the reacting flow case.

Incinerator having afterburner grate

Abstract: The invention relates to an incinerator (1) having a combustion chamber (2) that is at least partially enclosed by a housing (3), wherein the combustion chamber (2) has at least one ash outlet (4), to which at least one afterburner gate (5) for unburned components of ash (6) is allocated.

Nonlinear Dynamic Simulation of Turbomachinery Components and Systems

Abstract: The following chapters deal with the nonlinear transient simulation of turbomachinery systems. Power generation steam and gas turbine engines, combined cycle systems, aero gas turbine engines ranging from single spool engines to multi-spool high pressure core engines with an afterburner for supersonic flights, rocket propulsion systems and compression systems for transport of natural gas with a network of pipeline systems are a few examples of systems that heavily involve turbomachinery components.

Afterburner fuel-feed arrangement

Abstract: PROBLEM TO BE SOLVED: To extend operational life of a fuel spraybar device by minimizing vibration though an afterburner of a turbo-combustion engine is subjected to engine vibration under high temperatures.SOLUTION: A spraybar 28 of the afterburner fuel-feed arrangement 26 has a longitudinal axis and includes a spray head 34 in fluid communication with a plurality of elongate fuel pipes 38 surrounded by an elongate, aerodynamic-shaped shroud. The spray head 34 is mounted in a casing 16 and projects the surrounded fuel pipes 38 into an interior through-core of the engine in cross-wise orientation to a gas flow 20 thereof. The shroud has an interior lateral sidewall that includes a pipe-receiving portion configured to abuttingly engage a corresponding shroud-engaging portion of an exterior surface of the fuel pipe 38. The fuel pipes 38 are supported along their length, and when the pipes 38 are abuttingly engaged with the shroud, a braced configuration is stiffened which raises the eigenfrequencies into ranges higher than frequencies of the engine.