摘要
随着燃油车和重型农用机械数量的增加,石油资源消耗急剧上升,掺水乳化柴油作为一种新型可替代燃料受到了广泛关注。水核直径对掺水乳化柴油的微爆特性影响较大,但目前缺乏组分不变下的目标水核直径掺水乳化柴油的制备方法和适宜的水核直径表征方法。该研究基于CV模型,开发了适合水核微观结构的图像识别程序;创新性地提出采用对数正态分布函数拟合和表征水核直径的分布。结果表明,相对于索特平均直径,基于对数正态分布函数拟合的表征参数可以更准确地描述掺水乳化柴油内部水核分布情况。随后,基于正交设计方法,通过调节超声波乳化的乳化时间、乳化功率和超声波频率参数实现了组分不变情况下不同水核直径的掺水乳化柴油的制备;并基于新的表征参数,研究了制备参数对掺水乳化柴油中水核直径的影响规律以及敏感性等特征。研究表明:超声波频率、乳化功率和乳化时间3个制备因素对最大直径的极差为0.744、2.880、1.038,对分布标准差的极差分别为0.028、0.120、0.034,因此各因素的影响优先级分别为:乳化功率、乳化时间、超声波频率。随着乳化功率、乳化时间的增加,乳化效果明显增强,掺水乳化柴油中水核直径的拟合最大值与分布标准差逐渐减小,使得掺水乳化柴油中水核直径既小又平均,而超声波频率的影响则不明显;此外当水核直径及分布标准差减少到一定值后,增加乳化功率比增长乳化时间对掺水乳化柴油水核的细化影响更大,该研究可为乳化柴油制备水供参考。
Consumption of petroleum resource has risen sharply in recent years with the increase in fuel vehicles and heavy machinery in mechanized intensive agriculture.A large amount of emitted pollution has posed a serious threat to the atmospheric environment,even to body health in human survival.Water-in-oil(W/O)emulsified diesel fuel has received widespread attention for its ability to simultaneously remove nitrogen oxides and particulate matter.The micro-explosive characteristics of W/O fuel depend strongly on the diameter of the water core.But a systematic solution is still lacking in the preparation of W/O emulsified fuel for the target diameter of the water core at the constant component content.In this study,an image recognition system was first developed suitable for the microstructure of the water core in the W/O emulsified fuel using the Chan–Vese(CV)model.A log-normal function was proposed to fit the diameter distribution of the water core in the W/O emulsified fuel,thereby obtaining a new combination of characteristic parameters.An orthogonal test was selected to explore the influence of emulsification parameters on the diameter of the water core,including the emulsification time,emulsification power,and frequency parameters.The optimal parameters were achieved to fabricate the W/O emulsion with the target diameter of the water core.The results show that the CV model better identified the discrete boundary of the water core with smaller error,compared with manual recognition.The characteristics parameters from the lognormal function fitting can describe more accurately the diameter distribution of the water core in the W/O emulsified fuel,compared with the Sauter Mean Diameter(SMD).The maximum diameter of the water core and the standard deviation of diameter distribution gradually decreased,while the ultrasonic frequency imposed a relatively weak influence on the W/O emulsified fuel,as the emulsification time and power increased.When the diameter of the water core and the distribution reached a critical va
作者
王兆文
曹俊辉
袁波
王宇洲
吕嵩
成晓北
Wang Zhaowen;Cao Junhui;Yuan Bo;Wang Yuzhou;Lyu song;Cheng Xiaobei(Institute of Energy and Power Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2021年第6期235-242,共8页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(51576083).
关键词
柴油
参数
乳化液
水核直径
表征参数
正交设计
diesel fuels
parameter
emulsion
water core diameter
characterization parameter
orthogonal design
