氣助式及氣衝式平面噴嘴中霧化空氣量對噴霧特性之影響

Effects of Atomization Air with Air-Assist and Air-Blast Type Planar Injector

王覺寬(M. R. Wang) ； 徐明生(M. S. Sheu) ； 王承光(C. K. Wang) ； 林富祈(F. C. Lin)

《中國航空太空學會學刊》 29卷2期 (1997/06) Pp. 185-193

https://doi.org/10.6124/TAASRC.199706_29(2).11

摘要

本文主要以實驗方法探討霧化空氣量對於氣助式和氣衝式平面噴嘴霧化特性的影響。根據PDPA量測結果，發現在相同之霧化空氣量，氣助面噴嘴霧化特式平面噴嘴平均SMD比氣衝式噴嘴小很多，在相同SMD下，氣助式噴霧所需霧化空氣量僅爲氣衝式的三分之一。就粒徑分佈看來，氣助式噴霧粒徑分佈較集中，且粒徑的大小變化較少。而氣衝式噴霧的粒徑分佈則較爲分散，其大小變化亦較寬，且小粒子在噴霧中心處較多，而大粒子由中心至外綠顯著增加。速度分佈方面，兩種噴嘴軸向速度的最大值皆位於噴霧中心，但氣助式軸向速度約爲氣衝式的三位左右。在粒子密度和體積流通率方面，氣助式噴霧呈中空式的噴霧分佈，而氣衝式則爲實心式之噴霧。故吾人可以針對實際噴霧的需求選擇不同噴嘴器之設計：若希望以較小的霧化空氣量，得到較小的平均粒徑和較均勻的顆粒，可使用氣助式噴霧；若希望以較低的霧化空氣壓力得到體積流通率分佈較均勻的噴霧，則以採使用氣衝式噴霧爲宜。

關鍵字

霧化器 ； 氣衝式 ； 氣助式 ； 霧化空氣

並列摘要

The performances of the air-assist and the air-blast planar injectors with different atomization air are investigated. The sprays are measured by the two-component PDPA system. Under the same atomization air, the SMD of the air-assist type injector is smaller than that of the air-blast type. Furthermore, to produce the same SMD, the atomization air required for the first type injector is only one third of the other type. Analysis of the histogram shows that the distributions of the droplets for the air-assist injector are more concentrated than the air-blast type. This implies that the distributions of the air-assist spray are more uniform than those of the air-blast. Moreover, comparing the number density and volume flux, the air-assist spray shows a hollow cone spray pattern but the air-blast spray shows a solid cone one. The above characteristics of the injectors can be considered as a guideline to choose the proper injectors needed in the practical applications.

並列關鍵字

Atomizer ； Air-assist ； Air-blast ； Atomization air