Effects of interfacial forces on the evaporation of a superheated water droplet in hot immiscible oil

✍ Scribed by F.C.H. Jongenelen; F. Groeneweg; J.H. Gouda

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 499 KB
• Volume: 33
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(78)80057-8

✦ Synopsis

The release of vapour bubbles from the surface of a superheated water droplet submerged m a hot tmmlsclble OIL has been studied Theoretical calcukatlons Indicate that the maximum bubble size and the residence time of the vapour bubble at the odlwater interface, are controlled by the difference between the surface tensions at the odlvapour and waterlvapour Interfaces The mterfaclal forces act on the vapour bubble as a net force directed towards the od phase If the difference between the mterfacml forces ts substanttal. the formatlon of strings of vapour bubbles can be predicted When this difference IS lowered by adding surfactant to the system, the bubble size and its residence time at the odlwater Interface increase, which was coniktned by experunent In the absence of a surfactant, there IS a large dtlference between the respective surface tensions. and as a result a stnng of tiny (0 2 mm) vapour bubbles IS released from the ad/water Interface for l-2 mm untd the water droplet evaporates explosively, gtvmg nse to the formation of a very large (40 mm) vapour bubble In the presence of a surfactant (low difference between surface tensions) the medium sue (5 mm) vapour bubble elongates the water droplet, finally causing timely fragmentation of the droplet