Fluid Mechanics Seminar: John M. Frostad

Complex, multiphase fluids such as suspensions, emulsions, and foams are ubiquitous in industrial processes and consumer products. For example, vesicles and emulsion droplets can be used to stabilize nutraceuticals in foods to produce so-called “functional foods”. Also, polymeric microcapsules are enabling the development of a completely synthetic, blood replacement. On the other hand, foaming of hydraulic and lubricating fluids can cause mechanical damage to moving parts in machinery. In each of these examples, the properties of individual particles and interfaces can dramatically influence the functionality, stability, and rheology of the bulk system. Therefore, understanding these properties is critical to improving process efficiency and developing new products.

In this seminar, I will describe two experimental techniques that I have developed for studying multiphase systems. First, I will describe a Cantilevered-Capillary Force Apparatus for measuring/applying forces on individual, colloidal-sized particles including vesicles, droplets, and bubbles. Second, I will describe a technique that uses reflection interference microscopy to track the dynamics of thin films of fluid (< 5 microns thick). These types of films are formed between bubbles in a foam and are important for determining properties like the stability and density of the foam. Some of the results obtained with each technique will be highlighted.

Bio: John Frostad is an Assistant Professor at UBC with joint appointments in Chemical Engineering and Food Science. Dr. Frostad received his BS (with honors) from the University of Washington and PhD from the University of California, Santa Barbara, both in Chemical Engineering. After receiving his PhD, he worked for 2 years at Bend Research, a division of Capsugel, as a Research Chemical Engineer, and then worked as a postdoctoral scholar at Stanford before coming to UBC in 2016.

Please also join us for coffee and cookies before the talk in the PIMS Lounge (ESB 4133)