PRF50燃料低温重整产物对中等负荷下发动机燃烧及排放特性影响的研究

采用试验的方法,利用重整器和发动机台架研究了正庚烷和异辛烷体积比1∶1的PRF50燃料在不同重整温度下的低温重整产物及其对压燃发动机中等负荷下燃烧和排放特性的影响。研究结果表明,PRF50燃料在450K～750K的重整温度下低温反应放热量较少,重整器内温度基本不变。重整产物中的轻烃分子对发动机燃烧具有促进作用,可以使燃料重心(CA50)提前,而产物中的CO、CO_2对燃烧具有抑制作用;随着重整温度的提升,重整产物促进作用逐渐增强,达到最高值后逐渐减弱;在相同喷油时刻下,随着重整温度的增加,指示热效率先逐渐升高后降低,最多提高2%。

Investigation on the Effect of Low Temperature Reformed Products of PRF50 Fuel on Engine Combustion and Emission Characteristics Under Medium Load

The low temperature reformed products of PRF50 operation at different reforming temperature and their effects on engine combustion and emission characteristics under medium load were investigated by using a reformer and an engine test bed. Results show that the use of PRF50 fuel releases a small amount of heat in the low temperature reaction at the reforming temperature of 450 K to 750 K, while the temperature inside the reformer remains essentially unchanged. The light hydrocarbon molecules in the reformed products can promote the engine combustion to advance the angle of 50% mass fraction burned(CA50), and the CO and CO2 in the reformed products have an inhibitory effect on combustion. As the reforming temperature increases, the promoting effect of the reformed products increases first and then decreases gradually after reaching the highest value. Moreover, at the same injection timing, as the reforming temperature increases, the indicated thermal efficiency increases first and then begins to decrease after reaching a peak of 2%.