The Experts below are selected from a list of 497724 Experts worldwide ranked by ideXlab platform
V.s. Ivanov - One of the best experts on this subject based on the ideXlab platform.
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three dimensional numerical simulation of a continuously rotating detonation in the annular combustion chamber with a wide gap and separate delivery of fuel and oxidizer
Progress in Propulsion Physics, 2016Co-Authors: S M Frolov, A V Dubrovskii, V.s. IvanovAbstract:The possibility of integrating the Continuous Detonation Chamber (CDC) in a gas turbine engine (GTE) is demonstrated by means of three-dimensional (3D) numerical simulations, i. e., the feasibility of the Operation Process in the annular combustion chamber with a wide gap and with separate feeding of fuel (hydrogen) and oxidizer (air) is proved computationally. The CDC with an upstream isolator damping pressure disturbances propagating towards the compressor is shown to exhibit a gain in the total pressure of 15% as compared with the same combustion chamber operating in the deflagration mode.
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erratum to three dimensional numerical simulation of the Operation Process in a continuous detonation combustor with separate feeding of hydrogen and air
Russian Journal of Physical Chemistry B, 2015Co-Authors: A V Dubrovskii, V.s. Ivanov, SERGEY MIHAYLOVICH FROLOVAbstract:To verify the predictability of a computational technology developed at the Semenov Institute of Chemical Physics, Russian Academy of Sciences, three-dimensional calculations of the Operation Process in a hydrogen-air continuous detonation combustor (CDC) of the Lavrent’ev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences have been conducted with the reproduction of the geometrical dimensions of all the elements of the experimental combustor and the main operating conditions. The calculation results are in good agreement with the experiment data on all the measured characteristics. The problem of the applicability of a planar two-dimensional approximation with periodic boundary conditions to the simulation of the physicochemical Processes in an annular CDC has been specifically studied. It has been shown that the distributions of density, temperature, Mach number, and axial velocity component in the different sections of the combustor are substantially three-dimensional, whereas the static pressure distribution approaches a two-dimensional pattern with increasing distance from the bottom of the CDC. The three-dimensional calculations have shown that the conventional assumption of a supersonic discharge at the outlet of a two-dimensional computational domain is not always correct: extensive zones of a subsonic discharge of detonation products can exist in the outlet section.
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three dimensional numerical simulation of the Operation Process in a continuous detonation combustor with separate feeding of hydrogen and air
Russian Journal of Physical Chemistry B, 2015Co-Authors: A V Dubrovskii, V.s. Ivanov, S M FrolovAbstract:To verify the predictability of a computational technology developed at the Semenov Institute of Chemical Physics, Russian Academy of Sciences, three-dimensional calculations of the Operation Process in a hydrogen-air continuous detonation combustor (CDC) of the Lavrent’ev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences have been conducted with the reproduction of the geometrical dimensions of all the elements of the experimental combustor and the main operating conditions. The calculation results are in good agreement with the experiment data on all the measured characteristics. The problem of the applicability of a planar two-dimensional approximation with periodic boundary conditions to the simulation of the physicochemical Processes in an annular CDC has been specifically studied. It has been shown that the distributions of density, temperature, Mach number, and axial velocity component in the different sections of the combustor are substantially three-dimensional, whereas the static pressure distribution approaches a two-dimensional pattern with increasing distance from the bottom of the CDC. The three-dimensional calculations have shown that the conventional assumption of a supersonic discharge at the outlet of a two-dimensional computational domain is not always correct: extensive zones of a subsonic discharge of detonation products can exist in the outlet section.
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three dimensional numerical simulation of Operation Process in rotating detonation engine
Progress in Propulsion Physics, 2013Co-Authors: S M Frolov, A V Dubrovskii, V.s. IvanovAbstract:The aim of this work was to create an e©cient tool for transient threedimensional (3D) numerical simulation of the Operation Process in a Rotating DetonationEngine (RDE) with the particularemphasis to the design issues of the combustion chamber and isolators, thermal management and Operation control. The governing equations are unsteady Reynolds-Averaged NavierStokes (URANS) equations coupled with a turbulence model and with the continuity and energy equations for a multicomponent reactive mixture. The algorithm used is the combinationofFiniteVolumeMethodandParticleMethodrecentlydevelopedat ICPtotreatsimultaneouslyfrontalandvolumetriccombustion. ThecapabilitiesofthenewnumericaltoolhavebeendemonstratedfortheannularcylindricalRDEoperatingonhomogeneousstoichiometrichydrogen air mixture with a detonation rotationfrequency of about 126,000rpm. The calculations revealed considerable temperature and pressure pulsations at RDE inlet and outlet; however,special design adaptations were shown to allow their reduction.
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numerical simulation of the Operation Process and thrust performance of an air breathing pulse detonation engine in supersonic flight conditions
Russian Journal of Physical Chemistry B, 2011Co-Authors: V.s. Ivanov, SERGEY MIHAYLOVICH FROLOVAbstract:Multidimensional simulations of the unsteady gasdynamic flow in the duct of an air-breathing pulse detonation engine (ABPDE) operating on propane gas and the flow around it in supersonic flight at Mach numbers M of 3.0 and an altitude of 9.3 and 16 km are performed. It is shown that, at a length and diameter of the duct of 2.12 m and 83 mm, respectively, an ABPDE with an air intake and a nozzle can operate in a cyclic mode at a repetition frequency of 48 Hz, with a rapid deflagration-to-detonation transition (DDT) occurring at a distance of 5–6 combustion chamber diameters. To determine the thrust performance of the ABPDE in flight conditions, a series of working cycles were simulated with consideration given to the external flow around the engine. Calculations showed that the specific impulse of the ABPDE is approximately 1700 s. This value is much higher than the specific impulse typical of ramjet engines operating on conventional combustion (1200–1500 s) and substantially lower than the specific impulse obtained for the atmospheric conditions at sea level at zero flight velocity (∼2500 s).
S M Frolov - One of the best experts on this subject based on the ideXlab platform.
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flow structure in rotating detonation engine with separate supply of fuel and oxidizer experiment and cfd
2018Co-Authors: S M Frolov, V S Aksenov, Vladislav S Ivanov, Sergey N Medvedev, I O ShamshinAbstract:The experimental and computational investigations of detonation liquid rocket engine (DLRE) operating on natural gas (NG) – oxygen mixture have been performed to examine the impact of the DLRE configuration and fuel supply parameters on the Operation Process and thrust performance. In experiments, the absolute pressures of NG and oxygen supply were up to 30 and 15 atm, respectively; the mass flow rate of the reactive mixture was varied from 0.05 to 0.7 kg/s; the overall mixture composition was varied from fuel lean (with equivalence ratio 0.5) to fuel rich (with equivalence ratio 2.0). The maximum thrust and the maximum specific impulse obtained in this experimental series was 75 kgf and 160 s, respectively, at the maximum average pressure in the combustor of about 10 atm. It is shown that the increase of static pressure in the combustor results in the increase of both engine thrust and specific impulse. With the growth of the specific mass flow rate of reactive mixture, the Operation Process, on the one hand, becomes more stable, and on the other hand, the number of detonation waves simultaneously rotating in one direction in the combustor annulus increases. The results of DLRE fire tests were used to explore the predictive capabilities of the Semenov Institute of Chemical Physics (ICP) computational technology designed for full-scale simulation of the Operation Process in continuous-detonation combustors. Comparison of the predicted results with measurements proved that the calculations accurately predict the number of detonation waves circulating in the tangential direction of the annular DLRE combustor and the chaotic near-limiting Operation mode resembling the mode with longitudinally pulsating detonation in the DLRE with CD nozzle extension. Calculations predict with reasonable accuracy both the detonation propagation velocity and detonation rotation frequency. In addition, calculations correctly predict the trends in the variation of DLRE Operation parameters in an engine of a particular design. As in the experiments, the use of nozzle extension increases thrust. As for the thrust values, the calculations were shown to systematically overestimate them by at least 27% compared with measurements.
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three dimensional numerical simulation of a continuously rotating detonation in the annular combustion chamber with a wide gap and separate delivery of fuel and oxidizer
Progress in Propulsion Physics, 2016Co-Authors: S M Frolov, A V Dubrovskii, V.s. IvanovAbstract:The possibility of integrating the Continuous Detonation Chamber (CDC) in a gas turbine engine (GTE) is demonstrated by means of three-dimensional (3D) numerical simulations, i. e., the feasibility of the Operation Process in the annular combustion chamber with a wide gap and with separate feeding of fuel (hydrogen) and oxidizer (air) is proved computationally. The CDC with an upstream isolator damping pressure disturbances propagating towards the compressor is shown to exhibit a gain in the total pressure of 15% as compared with the same combustion chamber operating in the deflagration mode.
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three dimensional numerical simulation of the Operation Process in a continuous detonation combustor with separate feeding of hydrogen and air
Russian Journal of Physical Chemistry B, 2015Co-Authors: A V Dubrovskii, V.s. Ivanov, S M FrolovAbstract:To verify the predictability of a computational technology developed at the Semenov Institute of Chemical Physics, Russian Academy of Sciences, three-dimensional calculations of the Operation Process in a hydrogen-air continuous detonation combustor (CDC) of the Lavrent’ev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences have been conducted with the reproduction of the geometrical dimensions of all the elements of the experimental combustor and the main operating conditions. The calculation results are in good agreement with the experiment data on all the measured characteristics. The problem of the applicability of a planar two-dimensional approximation with periodic boundary conditions to the simulation of the physicochemical Processes in an annular CDC has been specifically studied. It has been shown that the distributions of density, temperature, Mach number, and axial velocity component in the different sections of the combustor are substantially three-dimensional, whereas the static pressure distribution approaches a two-dimensional pattern with increasing distance from the bottom of the CDC. The three-dimensional calculations have shown that the conventional assumption of a supersonic discharge at the outlet of a two-dimensional computational domain is not always correct: extensive zones of a subsonic discharge of detonation products can exist in the outlet section.
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three dimensional numerical simulation of Operation Process in rotating detonation engine
Progress in Propulsion Physics, 2013Co-Authors: S M Frolov, A V Dubrovskii, V.s. IvanovAbstract:The aim of this work was to create an e©cient tool for transient threedimensional (3D) numerical simulation of the Operation Process in a Rotating DetonationEngine (RDE) with the particularemphasis to the design issues of the combustion chamber and isolators, thermal management and Operation control. The governing equations are unsteady Reynolds-Averaged NavierStokes (URANS) equations coupled with a turbulence model and with the continuity and energy equations for a multicomponent reactive mixture. The algorithm used is the combinationofFiniteVolumeMethodandParticleMethodrecentlydevelopedat ICPtotreatsimultaneouslyfrontalandvolumetriccombustion. ThecapabilitiesofthenewnumericaltoolhavebeendemonstratedfortheannularcylindricalRDEoperatingonhomogeneousstoichiometrichydrogen air mixture with a detonation rotationfrequency of about 126,000rpm. The calculations revealed considerable temperature and pressure pulsations at RDE inlet and outlet; however,special design adaptations were shown to allow their reduction.
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experimental demonstration of the Operation Process of a pulse detonation liquid rocket engine
Russian Journal of Physical Chemistry B, 2011Co-Authors: S M Frolov, V S Aksenov, V.s. IvanovAbstract:A low-frequency demonstrator of the Operation Process of a pulse-detonation liquid-fuel rocket engine, intended for shaping the future design of a new type of rocket engines for spacecraft control, is for the first time developed and tested. As a result, the conditions are determined under which the demonstrator provides reliable deflagration-to-detonation transition (DDT) in a single-pulse or repetition mode. Because DDT occurs within a very short distance (less than 10 bores of the detonation tube), the operating frequency of the demonstrator can be substantially increased.
Jianji Wang - One of the best experts on this subject based on the ideXlab platform.
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ionic liquid promoted multi component reaction novel and efficient preparation of pyrazolo 3 4 b pyridinone pyrazolo 3 4 b quinolinone and their hybrids with pyrimidine nucleoside
Molecular Diversity, 2010Co-Authors: Xinying Zhang, Xuesen Fan, Xia Wang, Jianji WangAbstract:The utilization of an ionic liquid, [bmim][BF4] as both reaction medium and promoter for a multi-component reaction of aldehyde (1) and 5-amino-3-methyl-1-phenylpyrazole (2) with Meldrum acid (3) or dimedone (5) is studied. From this reaction, pyrazolo[3,4-b]pyridinone (4) and pyrazolo[3,4-b]quinolinone (6) derivatives were prepared in high yields. This novel procedure showed such advantages as environmentally benign nature, enhanced efficiency, simple Operation Process, and mild reaction conditions. As an application, the procedure was successfully used in the preparation of a set of pyrimidine nucleoside–pyrazolo[3,4-b]pyridine and pyrazolo[3,4-b]quinolinone hybrids with potential biological activities.
SERGEY MIHAYLOVICH FROLOV - One of the best experts on this subject based on the ideXlab platform.
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erratum to three dimensional numerical simulation of the Operation Process in a continuous detonation combustor with separate feeding of hydrogen and air
Russian Journal of Physical Chemistry B, 2015Co-Authors: A V Dubrovskii, V.s. Ivanov, SERGEY MIHAYLOVICH FROLOVAbstract:To verify the predictability of a computational technology developed at the Semenov Institute of Chemical Physics, Russian Academy of Sciences, three-dimensional calculations of the Operation Process in a hydrogen-air continuous detonation combustor (CDC) of the Lavrent’ev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences have been conducted with the reproduction of the geometrical dimensions of all the elements of the experimental combustor and the main operating conditions. The calculation results are in good agreement with the experiment data on all the measured characteristics. The problem of the applicability of a planar two-dimensional approximation with periodic boundary conditions to the simulation of the physicochemical Processes in an annular CDC has been specifically studied. It has been shown that the distributions of density, temperature, Mach number, and axial velocity component in the different sections of the combustor are substantially three-dimensional, whereas the static pressure distribution approaches a two-dimensional pattern with increasing distance from the bottom of the CDC. The three-dimensional calculations have shown that the conventional assumption of a supersonic discharge at the outlet of a two-dimensional computational domain is not always correct: extensive zones of a subsonic discharge of detonation products can exist in the outlet section.
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numerical simulation of the Operation Process and thrust performance of an air breathing pulse detonation engine in supersonic flight conditions
Russian Journal of Physical Chemistry B, 2011Co-Authors: V.s. Ivanov, SERGEY MIHAYLOVICH FROLOVAbstract:Multidimensional simulations of the unsteady gasdynamic flow in the duct of an air-breathing pulse detonation engine (ABPDE) operating on propane gas and the flow around it in supersonic flight at Mach numbers M of 3.0 and an altitude of 9.3 and 16 km are performed. It is shown that, at a length and diameter of the duct of 2.12 m and 83 mm, respectively, an ABPDE with an air intake and a nozzle can operate in a cyclic mode at a repetition frequency of 48 Hz, with a rapid deflagration-to-detonation transition (DDT) occurring at a distance of 5–6 combustion chamber diameters. To determine the thrust performance of the ABPDE in flight conditions, a series of working cycles were simulated with consideration given to the external flow around the engine. Calculations showed that the specific impulse of the ABPDE is approximately 1700 s. This value is much higher than the specific impulse typical of ramjet engines operating on conventional combustion (1200–1500 s) and substantially lower than the specific impulse obtained for the atmospheric conditions at sea level at zero flight velocity (∼2500 s).
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combustion explosion and shock waves numerical simulation of the Operation Process and thrust performance of an airbreathing pulse detonation engine in supersonic flight conditions
2011Co-Authors: V.s. Ivanov, SERGEY MIHAYLOVICH FROLOVAbstract:Multidimensional simulations of the unsteady gasdynamic flow in the duct of an airbreathing pulse detonation engine (ABPDE) operating on propane gas and the flow around it in supersonic flight at Mach numbers M of 3.0 and an altitude of 9.3 and 16 km are performed. It is shown that, at a length and diameter of the duct of 2.12 m and 83 mm, respectively, an ABPDE with an air intake and a nozzle can oper� ate in a cyclic mode at a repetition frequency of 48 Hz, with a rapid deflagrationtodetonation transition (DDT) occurring at a distance of 5-6 combustion chamber diameters. To determine the thrust performance of the ABPDE in flight conditions, a series of working cycles were simulated with consideration given to the external flow around the engine. Calculations showed that the specific impulse of the ABPDE is approximately 1700 s. This value is much higher than the specific impulse typical of ramjet engines operating on conven� tional combustion (1200-1500 s) and substantially lower than the specific impulse obtained for the atmo� spheric conditions at sea level at zero flight velocity (~2500 s).
A V Dubrovskii - One of the best experts on this subject based on the ideXlab platform.
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three dimensional numerical simulation of a continuously rotating detonation in the annular combustion chamber with a wide gap and separate delivery of fuel and oxidizer
Progress in Propulsion Physics, 2016Co-Authors: S M Frolov, A V Dubrovskii, V.s. IvanovAbstract:The possibility of integrating the Continuous Detonation Chamber (CDC) in a gas turbine engine (GTE) is demonstrated by means of three-dimensional (3D) numerical simulations, i. e., the feasibility of the Operation Process in the annular combustion chamber with a wide gap and with separate feeding of fuel (hydrogen) and oxidizer (air) is proved computationally. The CDC with an upstream isolator damping pressure disturbances propagating towards the compressor is shown to exhibit a gain in the total pressure of 15% as compared with the same combustion chamber operating in the deflagration mode.
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erratum to three dimensional numerical simulation of the Operation Process in a continuous detonation combustor with separate feeding of hydrogen and air
Russian Journal of Physical Chemistry B, 2015Co-Authors: A V Dubrovskii, V.s. Ivanov, SERGEY MIHAYLOVICH FROLOVAbstract:To verify the predictability of a computational technology developed at the Semenov Institute of Chemical Physics, Russian Academy of Sciences, three-dimensional calculations of the Operation Process in a hydrogen-air continuous detonation combustor (CDC) of the Lavrent’ev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences have been conducted with the reproduction of the geometrical dimensions of all the elements of the experimental combustor and the main operating conditions. The calculation results are in good agreement with the experiment data on all the measured characteristics. The problem of the applicability of a planar two-dimensional approximation with periodic boundary conditions to the simulation of the physicochemical Processes in an annular CDC has been specifically studied. It has been shown that the distributions of density, temperature, Mach number, and axial velocity component in the different sections of the combustor are substantially three-dimensional, whereas the static pressure distribution approaches a two-dimensional pattern with increasing distance from the bottom of the CDC. The three-dimensional calculations have shown that the conventional assumption of a supersonic discharge at the outlet of a two-dimensional computational domain is not always correct: extensive zones of a subsonic discharge of detonation products can exist in the outlet section.
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three dimensional numerical simulation of the Operation Process in a continuous detonation combustor with separate feeding of hydrogen and air
Russian Journal of Physical Chemistry B, 2015Co-Authors: A V Dubrovskii, V.s. Ivanov, S M FrolovAbstract:To verify the predictability of a computational technology developed at the Semenov Institute of Chemical Physics, Russian Academy of Sciences, three-dimensional calculations of the Operation Process in a hydrogen-air continuous detonation combustor (CDC) of the Lavrent’ev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences have been conducted with the reproduction of the geometrical dimensions of all the elements of the experimental combustor and the main operating conditions. The calculation results are in good agreement with the experiment data on all the measured characteristics. The problem of the applicability of a planar two-dimensional approximation with periodic boundary conditions to the simulation of the physicochemical Processes in an annular CDC has been specifically studied. It has been shown that the distributions of density, temperature, Mach number, and axial velocity component in the different sections of the combustor are substantially three-dimensional, whereas the static pressure distribution approaches a two-dimensional pattern with increasing distance from the bottom of the CDC. The three-dimensional calculations have shown that the conventional assumption of a supersonic discharge at the outlet of a two-dimensional computational domain is not always correct: extensive zones of a subsonic discharge of detonation products can exist in the outlet section.
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three dimensional numerical simulation of Operation Process in rotating detonation engine
Progress in Propulsion Physics, 2013Co-Authors: S M Frolov, A V Dubrovskii, V.s. IvanovAbstract:The aim of this work was to create an e©cient tool for transient threedimensional (3D) numerical simulation of the Operation Process in a Rotating DetonationEngine (RDE) with the particularemphasis to the design issues of the combustion chamber and isolators, thermal management and Operation control. The governing equations are unsteady Reynolds-Averaged NavierStokes (URANS) equations coupled with a turbulence model and with the continuity and energy equations for a multicomponent reactive mixture. The algorithm used is the combinationofFiniteVolumeMethodandParticleMethodrecentlydevelopedat ICPtotreatsimultaneouslyfrontalandvolumetriccombustion. ThecapabilitiesofthenewnumericaltoolhavebeendemonstratedfortheannularcylindricalRDEoperatingonhomogeneousstoichiometrichydrogen air mixture with a detonation rotationfrequency of about 126,000rpm. The calculations revealed considerable temperature and pressure pulsations at RDE inlet and outlet; however,special design adaptations were shown to allow their reduction.
