超声波悬浮TBAB溶液液滴表面半笼型水合物生长过程研究

Study on growth process of semiclathrate hydrate on the surface of TBAB solution droplets suspended by ultrasonic

利用超声波悬浮技术将四丁基溴化铵(TBAB)溶液液滴悬浮,观测了不同TBAB质量分数(15%、20%、25%)时的水合物生长过程,并与悬挂液滴进行了对比。实验发现,超声波悬浮的液滴处于快速旋转状态,液滴呈扁球状,水合物生长速率较快,但当液滴中含有气泡时生成水合物的诱导时间延长。总结出超声波悬浮状态下TBAB水合物生长方式可以分为两大类:由内而外,由外而内。由外而内又可以分为单平顶式、双平顶式和包裹式。建立悬浮液滴和悬挂液滴的传热模型,通过对比发现,超声波可以加快悬浮液滴的传热效率,加速水合物的生成和生长。该实验为观测水合物生长提供了一种新的方法。

Tetrabutylammonium bromide(TBAB)aqueous solution droplets were suspended by ultrasonic levitation technique.The hydrate growth process at different TBAB mass fraction(15%,20%,25%)was observed and compared with the pendent droplets.Experiments show that the droplets suspended by ultrasonic are in a state of rapid rotation,the droplets are oblate spheroids,and the hydrate growth rate is faster,but when the droplets contain bubbles,the induction time of hydrate formation is prolonged.It is concluded that the growth mode of TBAB hydrate in ultrasonic suspension can be divided into two categories:from inside to outside and from outside to inside.From the outside to the inside,it can be divided into three types:single flat top,double flat top and wrapped.The heat transfer models of suspension droplets and pendent droplets are established.Through comparison,it is found that ultrasonic can improve the heat transfer efficiency of suspension droplets,accelerate the formation and growth of hydrate.This experiment provides a new method for observing hydrate formation.