硝酸异丙酯含量对正庚烷激波诱导点火的影响OA

In order to understand the promoting effect of isopropyl nitrate(IPN)as an energetic sensitizer on shock wave induced ignition of n-heptane(HP),a shock tube experimental platform was used,combined with pneumatic atomi-zation and high-speed camera technology,to investigate the effects of IPN mass fraction(0,10%,20%,30%)and inci-dent shock wave pressure(8 000,9 000,11 000 kPa)on the shock wave induced ignition characteristics of HP.The re-sults show that the single-component HP fails to ignite at 1 051-1 317 K.The addition of IPN significantly reduces ignition delay time,and the critical mass fraction for ignition ranges from 10%to 20%at 9 000 kPa.When the mass fraction of IPN increases from20%to30%,the ignition delay time is shortened by about 37.5%,and the flame propagation speed increases from 2.75 mm/μs to 3.57 mm/μs,with an increase of 29.8%.Increasing the intensity of shock waves can also promote ignition,but the effect weakens with the increase of IPN.Fuels with low IPN content are more sensitive to changes in shock wave intensity.The synergistic mechanism of IPN chemical sensitization and shock wave physical compression in promoting ignition of hydrocarbon fuels was revealed,providing experimental basis for fuel design and combustion control under extreme conditions.