Micro gravity Lab

The Department of Mechanical Engineering established a Micro gravity lab.

Experimental facilities:

• Masurement of diffusion coefficients of binary mixtures using optical technique i.e. Mach-Zehnder interferometer.
• Measurement of refractive index using both optical technique and automatic refractometer (Abbemat WR-MW, Anton Paar).
• Measurement of liquid density using automatic density meter (DMA 5000 M, Anton Paar)

A spatial concentration difference within a mixture is the most common driving force for mass diffusion. In a homogeneous non-isothermal solution, temperature or pressure gradients may also cause mass diffusion. Mass diffusion due to a temperature gradient is called thermodiffusion or Soret effect, discovered by Ludwig (1856) and established by Soret (1879). Thermodiffusion is a coupled heat and mass transfer phenomenon. Thermodiffusion has applications in several important processes in nature and technology, exemplified by its crucial role in planning for oil extraction from the hydrocarbon reservoirs, which are subjected to relatively large temperature gradients. Other applications are in the isotopic separation of liquid metals and other separation applications, in emerging applications, such as particle manipulation by a temperature gradient (also known as thermophoresis), for microfluidic applications (Piazza 2008), and in optical screening methods for biomolecules and colloids (Duhr and Braun 2006). Therefore, due to the importance of thermodiffusion, we propose to conduct experiments in space and on the ground to obtain experimental data that includes diffusion in ternary systems, as needed to model any convective or transient process. The experimental data are used to validate existing thermodiffusion theories and develop physical and mathematical models for the estimation of the thermal diffusion factors and its applications to process studies needed also diffusion.