The two-phase volume-averaged model with the detailed chemistry reaction mechanism GRI 3.0 was adopted in the quasi-steady-state simulation of hydrogen production by CH4-rich filtration combustion in an alumina foam u...The two-phase volume-averaged model with the detailed chemistry reaction mechanism GRI 3.0 was adopted in the quasi-steady-state simulation of hydrogen production by CH4-rich filtration combustion in an alumina foam under fully developed conditions. The relations among the combustion wave velocity, the inlet gas velocity and the equivalence ratio were discussed, and their influences on the distributions of temperature and species in the alumina foam and on H2 yield, CH4 conversion, H2 selectivity and CO selectivity were analyzed in detail. The results show that the combustion wave velocity increases with the increase of equivalence ratio or inlet gas velocity. The H2 yield exceeded 50% with equivalence ratio between 2.0 and 3.0 and combustion wave velocity larger than 0.4 mm/s. The H2 selectivity exceeded 50% with equivalence ratio larger than 2.0 and CO selectivity exceeded 80% with equivalence ratio between 1.8 and 2.0 and combustion wave velocity larger than 0.4 mm/s.展开更多
In this study, kerosene fuel-rich gas produced by the combustion in the gas generator was used as the fuel and oxygen-rich air was used as the oxidant to investigate the propagation characteristics of the rotating det...In this study, kerosene fuel-rich gas produced by the combustion in the gas generator was used as the fuel and oxygen-rich air was used as the oxidant to investigate the propagation characteristics of the rotating detonation wave (RDW). The initiation of the kerosene fuel-rich gas and propagation process of the RDW were analyzed. The influences of the oxygen content in the oxidizer, kerosene mass flow rate of the gas generator, and temperature of the kerosene fuel-rich gas on the propagation process of the RDW were studied. The experimental results revealed that the propagation velocity of the RDW could be improved by increasing the three parameters mentioned above with the kerosene mass flow rate as the strongest factor. The minimum oxygen content that could successfully initiate and maintain the stable propagation of the RDW was 32%, achieving the RDW velocity of 1141.9 m/s. The RDW mainly propagated as two-counter rotating waves and a single wave when the equivalent ratios were 0.62–0.79 and 0.85–0.87, respectively. The highest RDW velocity of 1637.2 m/s was obtained when the kerosene mass flow rate, oxygen content, and equivalent ratio were 74.6 g/s, 44%, and 0.87, respectively.展开更多
The mathematical property of one-dimensional steady solution for reverse smolder waves in the context of a model that permits both fuel-rich and fuel-lean has been studied using the method of analysis. Based on the eq...The mathematical property of one-dimensional steady solution for reverse smolder waves in the context of a model that permits both fuel-rich and fuel-lean has been studied using the method of analysis. Based on the equations and the boundary conditions some asymptotic properties of the solution at infinity are proved. It is shown that the value of oxygen or the mass of fuel （corresponding to the fuel-rich case and the fuel-lean case, respectively） tends to zero, and the temperature approaches to a fixed value. This is confirmed by other authors using large activation energy asymptotic methods.展开更多
A design method for a kerosene fuel-rich gas-generator of a liquid rocket engine using turbopumps to supply propellant was performed at a conceptual level. The gas-generator creates hot gases, enabling the turbine to ...A design method for a kerosene fuel-rich gas-generator of a liquid rocket engine using turbopumps to supply propellant was performed at a conceptual level. The gas-generator creates hot gases, enabling the turbine to operate the turbopumps. A chemical non-equilibrium analysis and a droplet vaporization model were used for the estimation of the burnt gas properties and characteristic chamber length. A premixed counter-flow flame analysis was performed for the prediction of the burnt gas properties, namely the temperature, the specific heat ratio and heat capacity, and the chemical reaction time. To predict the vaporization time, the Spalding model, using a single droplet in convective condition, was used. The minimum residence time in the chamber and the characteristic length were calculated by adding the reaction time and the vaporization time. Using the characteristic length, the design methods for the fuel-rich gas-generator were established. Finally, a parametric study was achieved for the effects of the O/F ratio, mass flow rate, chamber pressure, initial droplet temperature, initial droplet diameter and initial droplet velocity.展开更多
基金Supported by the China Postdoctoral Science Foundation (Grant No. 20080440713)the National Hi-Tech Research and Development Program ("863" Project) (Grant Nos. 2007AA05Z105, 2007AA05Z236)the National Natural Science Foundation of China (Grant No. 50776036)
文摘The two-phase volume-averaged model with the detailed chemistry reaction mechanism GRI 3.0 was adopted in the quasi-steady-state simulation of hydrogen production by CH4-rich filtration combustion in an alumina foam under fully developed conditions. The relations among the combustion wave velocity, the inlet gas velocity and the equivalence ratio were discussed, and their influences on the distributions of temperature and species in the alumina foam and on H2 yield, CH4 conversion, H2 selectivity and CO selectivity were analyzed in detail. The results show that the combustion wave velocity increases with the increase of equivalence ratio or inlet gas velocity. The H2 yield exceeded 50% with equivalence ratio between 2.0 and 3.0 and combustion wave velocity larger than 0.4 mm/s. The H2 selectivity exceeded 50% with equivalence ratio larger than 2.0 and CO selectivity exceeded 80% with equivalence ratio between 1.8 and 2.0 and combustion wave velocity larger than 0.4 mm/s.
文摘In this study, kerosene fuel-rich gas produced by the combustion in the gas generator was used as the fuel and oxygen-rich air was used as the oxidant to investigate the propagation characteristics of the rotating detonation wave (RDW). The initiation of the kerosene fuel-rich gas and propagation process of the RDW were analyzed. The influences of the oxygen content in the oxidizer, kerosene mass flow rate of the gas generator, and temperature of the kerosene fuel-rich gas on the propagation process of the RDW were studied. The experimental results revealed that the propagation velocity of the RDW could be improved by increasing the three parameters mentioned above with the kerosene mass flow rate as the strongest factor. The minimum oxygen content that could successfully initiate and maintain the stable propagation of the RDW was 32%, achieving the RDW velocity of 1141.9 m/s. The RDW mainly propagated as two-counter rotating waves and a single wave when the equivalent ratios were 0.62–0.79 and 0.85–0.87, respectively. The highest RDW velocity of 1637.2 m/s was obtained when the kerosene mass flow rate, oxygen content, and equivalent ratio were 74.6 g/s, 44%, and 0.87, respectively.
文摘The mathematical property of one-dimensional steady solution for reverse smolder waves in the context of a model that permits both fuel-rich and fuel-lean has been studied using the method of analysis. Based on the equations and the boundary conditions some asymptotic properties of the solution at infinity are proved. It is shown that the value of oxygen or the mass of fuel （corresponding to the fuel-rich case and the fuel-lean case, respectively） tends to zero, and the temperature approaches to a fixed value. This is confirmed by other authors using large activation energy asymptotic methods.
基金supported by the Output-oriented Project of the Collaborative Research Program with the Higher Education Partners of the Korea Aerospace Research Institute in 2009
文摘A design method for a kerosene fuel-rich gas-generator of a liquid rocket engine using turbopumps to supply propellant was performed at a conceptual level. The gas-generator creates hot gases, enabling the turbine to operate the turbopumps. A chemical non-equilibrium analysis and a droplet vaporization model were used for the estimation of the burnt gas properties and characteristic chamber length. A premixed counter-flow flame analysis was performed for the prediction of the burnt gas properties, namely the temperature, the specific heat ratio and heat capacity, and the chemical reaction time. To predict the vaporization time, the Spalding model, using a single droplet in convective condition, was used. The minimum residence time in the chamber and the characteristic length were calculated by adding the reaction time and the vaporization time. Using the characteristic length, the design methods for the fuel-rich gas-generator were established. Finally, a parametric study was achieved for the effects of the O/F ratio, mass flow rate, chamber pressure, initial droplet temperature, initial droplet diameter and initial droplet velocity.
