(Lisbon Symposia会议论文)间歇多点喷射雾化的瞬态雾化特征分析

This paper analysis the transient characteristics of intermittent sprays produced by the single-point impact of multiple cylindrical jets. The aim is to better understand the effect of varying the number of impinging jets in the atomization process, considering intermittent sprays which allow a more accurate control of the flow rate. Some considerations are made relatively to the applicability of intermittent multijet sprays for spray cooling. The results presented evidences that hydrodynamic mechanisms underlying the physics of ligament fragmentation in 2-impinging jets sprays, in the turbulent sheet regime because of required short atomization distances, also apply to sprays produced with more than 2 jets. Edge and detached ligaments have been identified and were associated with distinct droplet clusters, which become more evident as the number of impinging jets increases. This has been supported by size-velocity correlations and droplets produced by detached ligaments found predominant, as well as their axial velocity which becomes more uniformly distributed with 4-impinging jets. Multijet spray dispersion patterns suggest the potential geometric nature associated with these sprays, depending on the number of impinging jets. And, finally, the Weber number range suggests that multijet sprays are more likely to deposit on interposed surfaces, thus, becoming a promising and competitive atomization solution for improving spray cooling.