掺氢对高辛烷值燃料燃烧过程的影响

通过耦合纯H2和高辛烷值标准基础燃料(primary reference fuel,PRF)燃烧机理,在CHEMKIN的Premix子程序上建立并验证了PRF-H2混合燃料预混层流火焰燃烧模型,并在该模型上就理论当量比条件下,掺氢对高辛烷值燃烧过程的影响进行了计算研究.试验结果表明:H2能加快PRF-H2混合燃料火焰的传播,促进PRF-H2混合燃料中正庚烷和异辛烷的分解;此外,掺入H2还能增大火焰中H、O和OH自由基的摩尔分数,H自由基摩尔分数的最大值由纯PRF混合燃料火焰时的4×10-3增大到了掺氢能量分数为60%时的13×10-3.

Effect of Hydrogen Addition on Combustion of High Octane Number Fuels

The combustion mechanisms of pure hydrogen and primary reference fuel(PRF) were coupled to build the premix laminar flame burning model for the PRF-H2blends on the Premix code of CHEMKIN software,followed by numerically investigating the effect of hydrogen blends on the combustion process of high octane number fuel and the mole fraction variations of main species and H,O and OH radicals. Results show that H2blending promotes PRF-H2mixtures burning velocity and accelerates the dissociation of the n-heptane and iso-octane in the PRF-H2mixtures. Besides,the mole fractions of H,O and OH radicals also increased with an example that the maximum mole fraction of H radical rises from 4 × 10- 3to 13 × 10- 3as the hydrogen energy fraction varies from 0 to 60%.