Based on a constant volume combustion chamber

the effects of pilot and main injections of two-injection strategy as well as the dwell time between them on spray and combustion were studied. The spray was studied by using Mie-scattering imaging technique

and the combustion was investigated with the flame luminosity imaging and OH chemiluminescence techniques. The result shows that

compared with one-injection strategy

the ignition location of the main injection of two-injection strategy is closer to injector

and the ignition delay time and flame lift-off length are shorter. When using two-injection strategy

the spray cone angle of the main injection decreases and the ignition delay time increases with the increase of the dwell time. Besides

the dwell time has no obvious influence on the ignition location and flame lift-off length. The flame luminosity is the weakest when the dwell time is 0.9 ms and the strongest when the dwell time is 1.2 ms.