A reduced chemical kinetic model （44 species and 72 reactions） for the homogeneous charge compression ignition （HCCI） combustion of n-heptane was optimized to improve its autoignition predictions under different e...A reduced chemical kinetic model （44 species and 72 reactions） for the homogeneous charge compression ignition （HCCI） combustion of n-heptane was optimized to improve its autoignition predictions under different engine operating conditions. The seven kinetic parameters of the optimized model were determined by using the combination of a micro-genetic algorithm optimization methodology and the SENKIN program of CHEMKIN chemical kinetics software package. The optimization was performed within the range of equivalence ratios 0.2-1.2, initial temperature 310- 375 K and initial pressure 0, 1-0.3 MPa, The engine simulations show that the optimized model agrees better with the detailed chemical kinetic model （544 species and 2 446 reactions） than the original model does.展开更多
The thermal decomposition of n-heptane is an important process in petroleum industry. The theoretical investigations show that the main products are C2H4, H2, CH4, and C3H6, which agree well with the experimental resu...The thermal decomposition of n-heptane is an important process in petroleum industry. The theoretical investigations show that the main products are C2H4, H2, CH4, and C3H6, which agree well with the experimental results. The products populations depend strongly on the temperature. The quantity of ethylene increases quickly as the temperature goes up. The conversion of n-heptane and the mole fraction of primary products from reactive molecular dynamic and chemical kinetic modeling are compared with each other. We also investigated the pre-exponential factor and activation energy for thermal decomposition of n-heptane by kinetic analysis from the reactive force field simulations, which were extracted to be 1.78×10^14 s^-1 and 47.32 kcal/mol respectively.展开更多
A new reduced chemical kinetic model of 1-pentene is developed based on a detailed chemical kinetic model of 1-pentene at high temperature(194 species and 1266 reactions).By means of sensitivity and flow rate analyses...A new reduced chemical kinetic model of 1-pentene is developed based on a detailed chemical kinetic model of 1-pentene at high temperature(194 species and 1266 reactions).By means of sensitivity and flow rate analyses,32 important reactions are determined,on the basis of which a reduced chemical kinetic model consisting 50 species and 251 reactions is proposed through addition of other important species and reactions.The results show that the simulated cylinder pressure and temperature calculated using the reduced model agree well with those from the detailed model.The reduced model requires less computing time than the detailed model,which enables coupled computation of the chemical kinetic model with computational fluid dynamics.展开更多
基金SUPPORTED BY NATIONAL KEY BASIC RESEARCH PLAN ("973" PLAN, NO. 2001CB209202).
文摘A reduced chemical kinetic model （44 species and 72 reactions） for the homogeneous charge compression ignition （HCCI） combustion of n-heptane was optimized to improve its autoignition predictions under different engine operating conditions. The seven kinetic parameters of the optimized model were determined by using the combination of a micro-genetic algorithm optimization methodology and the SENKIN program of CHEMKIN chemical kinetics software package. The optimization was performed within the range of equivalence ratios 0.2-1.2, initial temperature 310- 375 K and initial pressure 0, 1-0.3 MPa, The engine simulations show that the optimized model agrees better with the detailed chemical kinetic model （544 species and 2 446 reactions） than the original model does.
基金This work was supported by the National Natural Science Foundation of China （No.21103117）.
文摘The thermal decomposition of n-heptane is an important process in petroleum industry. The theoretical investigations show that the main products are C2H4, H2, CH4, and C3H6, which agree well with the experimental results. The products populations depend strongly on the temperature. The quantity of ethylene increases quickly as the temperature goes up. The conversion of n-heptane and the mole fraction of primary products from reactive molecular dynamic and chemical kinetic modeling are compared with each other. We also investigated the pre-exponential factor and activation energy for thermal decomposition of n-heptane by kinetic analysis from the reactive force field simulations, which were extracted to be 1.78×10^14 s^-1 and 47.32 kcal/mol respectively.
基金supported by the National Natural Science Foundation of China (51106181)the State Key Laboratory of Engines in Tianjin University (K2012-06)Promotive Research Fund for Young and Middle-Aged Scientists of Shandong Province (BS2012NJ012)
文摘A new reduced chemical kinetic model of 1-pentene is developed based on a detailed chemical kinetic model of 1-pentene at high temperature(194 species and 1266 reactions).By means of sensitivity and flow rate analyses,32 important reactions are determined,on the basis of which a reduced chemical kinetic model consisting 50 species and 251 reactions is proposed through addition of other important species and reactions.The results show that the simulated cylinder pressure and temperature calculated using the reduced model agree well with those from the detailed model.The reduced model requires less computing time than the detailed model,which enables coupled computation of the chemical kinetic model with computational fluid dynamics.
