The Thermocapillary Migrations of Drop and Fluid in Microgravity Environment

Abstract

In this article, we consider that the geothermal gradient induces the surface tension gradient and the surface tension gradient induces longitudinal shear stress and fluid motion. The temperature gradient induces transfer of heat and matter. A theoretical solution of the velocity distribution of thin fluid film and the velocity of migration of oil are presented. Three experiments attest to the geothermal gradient is assuredly a driven force of the migration of oil. An experiment is mathematics simulation of migration of oil; the other two experiments are from literatures (Huang, C., Hu, L., & Kang, Q. (2005) Acta Mechanica Sinica, 37 (02), 232–237; Qiu, N. & Fang, J. (2003) Oil & Gas Geology, 24 (03), 210–214 [in Chinese].). All experiments show that under the action of an applied temperature difference the gradient of surface tension is formed. The consequence of variation of the surface tension due to a thermal gradient results in a tangential stress which, by viscous traction, causes the motion of neighboring fluid. The temperature difference and time control the migration velocity and distance. This also may effect accumulation and evolvement of oil/gas.

Keywords:

• Geothermal gradient
• migration
• surface tension
• transport