Comprehensive Mechanisms for Combustion Chemistry: An Experimental and Numerical Study with Emphasis on Applied Sensitivity Analysis

Dryer, Frederick L.

关键词: ADDITIVES;    BOMBS;    CHEMISTRY;    COMBUSTION;    COMPATIBILITY;    CONSTRUCTION;    DILUTION;    FLAMES;    HYDROCARBONS;    KINETICS;    LAMINAR FLAMES;    OXIDATION;    PYROLYSIS;    RADICALS;    REACTION KINETICS;    SCAVENGING;    SENSITIVITY ANALYSIS;    STAGNATION;   

DOI  :  10.2172/951070
RP-ID  :  86ER13503-14
PID  :  OSTI ID: 951070
Others  :  TRN: US201004%%405

学科分类：能源（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

This project was an integrated experimental/numerical effort to study pyrolysis and oxidation reactions and mechanisms for small-molecule hydrocarbon structures under conditions representative of combustion environments. The experimental aspects of the work were conducted in large-diameter flow reactors, at 0.3 to 18 atm pressure, 500 to 1100 K temperature, and 10^-2 to 2 seconds reaction time. Experiments were also conducted to determine reference laminar flame speeds using a premixed laminar stagnation flame experiment and particle image velocimetry, as well as pressurized bomb experiments. Flow reactor data for oxidation experiments include: (1)adiabatic/isothermal species time-histories of a reaction under fixed initial pressure, temperature, and composition; to determine the species present after a fixed reaction time, initial pressure; (2)species distributions with varying initial reaction temperature; (3)perturbations of a well-defined reaction systems (e.g. CO/H₂/O₂ or H₂/O₂)by the addition of small amounts of an additive species. Radical scavenging techniques are applied to determine unimolecular decomposition rates from pyrolysis experiments. Laminar flame speed measurements are determined as a function of equivalence ratio, dilution, and unburned gas temperature at 1 atm pressure. Hierarchical, comprehensive mechanistic construction methods were applied to develop detailed kinetic mechanisms which describe the measurements and literature kinetic data. Modeling using well-defined and validated mechanisms for the CO/H₂/Oxidant systems and perturbations of oxidation experiments by small amounts of additives were also used to derive absolute reaction rates and to investigate the compatibility of published elementary kinetic and thermochemical information. Numerical tools were developed and applied to assess the importance of individual elementary reactions to the predictive performance of the developed mechanisms and to assess the uncertainties in elementary rate constant evaluations.