ABSTRACT

A kinetic model is presented for high-temperature oxidation and combustion of the refrigerants: 2,3,3,3-tetrafluoropropene (R-1234yf), 1,3,3,3-tetrafluoropropene (R-1234ze(E)), and 3,3,3-trifluoropropene (R-1243zf) at atmospheric pressure. The kinetic model is based on: GRI-Mech-3.0 and previously developed models for the inhibition of hydrocarbon flames by 2-bromo-3,3,3-trifluoropropene (2-BTP) and C₁-C₂ hydrofluorocarbons. The model includes 1001 reactions and 105 species. Thermodynamic equilibrium calculations indicate a maximum combustion temperature of 2047 K, 2037 K, and 2312 K for R-1234yf, R-1234ze(E), and R-1243zf, respectively, in air for standard conditions. Calculations of the 1D, steady, adiabatic, laminar burning velocity for these refrigerants with air or oxygen-enriched air indicate reasonable agreement with experimental data from the literature when the burning velocity is above 10 cm/s. The simulations are used to understand the relevant reactions. Despite the relatively high F/H ratio in the reactants (2), the combustion is dominated by reactions with radical pool radicals typical of hydrocarbons (O, OH, and H). The combustion of R-1234yf or R-1234ze(E) is characterized by a two-zone flame, the second of which is a slow reaction zone accounting for CO and CF₂O consumption and additional temperature rise of a few hundred K. Simulations of the effects of water vapor on the burning velocity of R-1234yf and R-1234ze(E) capture qualitatively the trends in the experimental results. For certain values of the equivalence ratio and oxygen content of air, the premixed flame structure shows temperature peak in the main reaction zone higher than the equilibrium value.

摘要

提出了制冷剂高温氧化和燃烧的动力学模型：2,3,3,3-四氟丙烯 (R-1234yf)、1,3,3,3-四氟丙烯 (R-1234ze(E)) 和大气压下的 3,3,3-三氟丙烯 (R-1243zf)。动力学模型基于： GRI-Mech-3.0 和先前开发的用于抑制碳氢化合物火焰的 2-溴-3,3,3-三氟丙烯 (2-BTP) 和 C ₁ -C _{2 模型}氢氟烃。该模型包括 1001 个反应和 105 个物种。热力学平衡计算表明，在标准条件下，R-1234yf、R-1234ze(E) 和 R-1243zf 在空气中的最大燃烧温度分别为 2047 K、2037 K 和 2312 K。当燃烧速度高于 10 cm/s 时，这些制冷剂与空气或富氧空气的一维、稳定、绝热、层流燃烧速度的计算表明与文献中的实验数据合理一致。模拟用于理解相关反应。尽管反应物 (2) 中的 F/H 比相对较高，但燃烧主要是与烃类（O、OH 和 H）典型的自由基池自由基反应。R-1234yf 或 R-1234ze(E) 的燃烧特点是两区火焰，₂ O 消耗和几百 K 的额外温升。 水蒸气对 R-1234yf 和 R-1234ze(E) 燃烧速度影响的模拟定性地捕捉了实验结果的趋势。当当量比和空气氧含量一定时，预混火焰结构在主反应区出现高于平衡值的温度峰值。