The partial oxidation of hydrocarbons is an important technical route to produce acetylene for chemical industry.The partial oxidation reactor is the key to high acetylene yields.This work is an experimental and numer...The partial oxidation of hydrocarbons is an important technical route to produce acetylene for chemical industry.The partial oxidation reactor is the key to high acetylene yields.This work is an experimental and numerical study on the use of a methane flame to produce acetylene.A lab scale partial oxidation reactor was used to produce ultra fuel-rich premixed jet flames.The axial temperature and species concentration profiles were measured for different equivalence ratios and preheating temperatures,and these were compared to numerical results from Computational Fluid Dynamics(CFD)simulations that used the Reynolds Averaged Navier-Stokes Probability Density Function(RANS-PDF)approach coupled with detailed chemical mechanisms.The Leeds 1.5,GRI 3.0 and San Diego mechanisms were used to investigate the effect of the detailed chemical mechanisms.The effects of equivalence ratio and preheating temperature on acetylene production were experimentally and numerically studied.The experimental validations indicated that the present numerical simulation provided reliable prediction on the partial oxidation of methane.Using this simulation method the optimal equivalence ratio for acetylene production was determined to be 3.6.Increasing preheating temperature improved acetylene production and shortened greatly the ignition delay time.So the increase of preheating temperature had to be limited to avoid uncontrolled ignition in the mixing chamber and the pyrolysis of methane in the preheater.展开更多
A reduced combustion kinetic model for the methanol-gasoline blended fuels for SI engines was developed. Sensitivity analysis and rate constant variation methods were used to optimize the kinetic model. Flame propagat...A reduced combustion kinetic model for the methanol-gasoline blended fuels for SI engines was developed. Sensitivity analysis and rate constant variation methods were used to optimize the kinetic model. Flame propagation, shock-tube and jet-stirred reactor systems were modeled in CHEMKIN. The laminar flame speed, ignition delay time and change in concentrations of species were simulated using the reduced kinetic model. The simulation results of reduced chemical mechanism agreed well with the relevant experimental data published in the literature. The experimental investigations on engine bench were also carried out. The in-cylinder pressure and exhaust emissions were obtained by using a combustion analyzer and an FTIR(Fourier transform infrared spectroscopy) spectrometer. Meanwhile, an engine in-cylinder CFD model was established in AVL FIRE and was coupled with the proposed reduced chemical mechanism to simulate the combustion process of methanol-gasoline blends. The simulated combustion process showed good agreement with the engine experimental results and the predicted emissions were found to be in accordance with the FTIR results.展开更多
基金Supported by the National Natural Science Foundation of China(20976090)the Foundation for the Author of National Excellent Doctoral Dissertation of China(200757)
文摘The partial oxidation of hydrocarbons is an important technical route to produce acetylene for chemical industry.The partial oxidation reactor is the key to high acetylene yields.This work is an experimental and numerical study on the use of a methane flame to produce acetylene.A lab scale partial oxidation reactor was used to produce ultra fuel-rich premixed jet flames.The axial temperature and species concentration profiles were measured for different equivalence ratios and preheating temperatures,and these were compared to numerical results from Computational Fluid Dynamics(CFD)simulations that used the Reynolds Averaged Navier-Stokes Probability Density Function(RANS-PDF)approach coupled with detailed chemical mechanisms.The Leeds 1.5,GRI 3.0 and San Diego mechanisms were used to investigate the effect of the detailed chemical mechanisms.The effects of equivalence ratio and preheating temperature on acetylene production were experimentally and numerically studied.The experimental validations indicated that the present numerical simulation provided reliable prediction on the partial oxidation of methane.Using this simulation method the optimal equivalence ratio for acetylene production was determined to be 3.6.Increasing preheating temperature improved acetylene production and shortened greatly the ignition delay time.So the increase of preheating temperature had to be limited to avoid uncontrolled ignition in the mixing chamber and the pyrolysis of methane in the preheater.
基金supported by the National Natural Science Foundation of China(Grant Nos.50776078&51106136)
文摘A reduced combustion kinetic model for the methanol-gasoline blended fuels for SI engines was developed. Sensitivity analysis and rate constant variation methods were used to optimize the kinetic model. Flame propagation, shock-tube and jet-stirred reactor systems were modeled in CHEMKIN. The laminar flame speed, ignition delay time and change in concentrations of species were simulated using the reduced kinetic model. The simulation results of reduced chemical mechanism agreed well with the relevant experimental data published in the literature. The experimental investigations on engine bench were also carried out. The in-cylinder pressure and exhaust emissions were obtained by using a combustion analyzer and an FTIR(Fourier transform infrared spectroscopy) spectrometer. Meanwhile, an engine in-cylinder CFD model was established in AVL FIRE and was coupled with the proposed reduced chemical mechanism to simulate the combustion process of methanol-gasoline blends. The simulated combustion process showed good agreement with the engine experimental results and the predicted emissions were found to be in accordance with the FTIR results.
