一种新型气泡雾化喷嘴水平喷射特性的研究

研究了一种新型锥面注气方式的气泡雾化喷嘴，用水和压缩空气在常温常压下试验了水平喷射时结构和工作参数对雾化及流场特性的影响，用2D-PDA测量了液雾的平均直径尺寸分布和速度分布。结果表明，注气孔的尺寸及数目均对雾化特性产生一定影响；气泡发生器的锥角存在一最佳值，对于本文研究的结构，60°锥角可达到良好的雾化；混合段长度也存在一最佳值范围，提高液体的喷射压力和气液比，能够改善雾化，增大液雾的速度。实验结果表明，锥面多孔注气能有效地抑制水平喷射情况下由浮力产生的气泡聚合，能够使气泡均匀分布，实现稳定、连续的雾化。

STUDY ON HORIZONTAL-INJECTING CHARACTERISTICS OF A NEW TYPE OF EFFERVESCENT ATOMIZERS

The atomizing and flow-field characteristics of a new type of effervescent have beenstudied under horizontal injecting, as well as the influences of gas-injector geometry and operatingconditions. The drop-size distribution and velocity of the spray are measured using a two-dimensionalParticle Dynamic Analyzer (PDA). All tests are carried out at normal atmospheric pressure andtemperature. Water injection pressures varied from 0. 30 to 0. 50 MPa and gas/liquid ratios from 0. 04to 0. 10 by mass. The results obtained show that gas-injector geometry, including the number and sizeof the gas-injector holes, the cone angles and the length of mixing section, have significant influenceon atomization qualities of horizontal-injecting effervescent atomizers. Furthermore, there exist anoptimum cone angle for the bubble generator and an optimum range of length of the mixing section,with which the gathering of bubbles and gas-liquid stratification caused by buoyancy can be restrainedeffectively and stable and continuous atomization with higher quality can be obtained.