We designed a hands-on laboratory exercise to demonstrate why injecting an aqueous polymer solution into an oil reservoir (commonly known as "polymer flooding") enhances oil production. Students are split into three groups of two to three. Each group is assigned to a packed Hele-Shaw cell pre-saturated with oil, our laboratory model of…

Plastic baggies, especially the sealable variety, seem to be a ubiquitous part of human culture. The zipper-type seal on plastic baggies is an example of an unappreciated engineering accomplishment that is relevant to everyday life. In fact, the challenge of fastening two pieces together probably dates back to the making of tools and clothing by…