# (1) Gas flows generated by spatially uniform and oscillatory heating of parallel plane walls, and (2) Newton - When bad is still good enough

*Applied Mathematics Student Seminar*

*by (1) Jason Nassios and (2) Daniel Ladiges*

*Institution:*The University of Melbourne

*Date: Tue 4th September 2012*

*Time: 1:00 PM*

*Location: Old Geology Theatre 2*

*Abstract*: (1) Gas flows such as those exhibited by nano scale systems have received considerable recent attention, with two pertinent classes emerging. The most widely discussed of these concerns flows driven by an oscillatory shearing force. Despite their comparative practical importance, analytical and numerical investigations of flows driven by oscillatory heating and cooling of a wall are less ubiquitous. In this talk, we utilise asymptotic theories to study the heating of two adjacent walls, and discuss some key features of the flow.

(2) In proposition 34 of his Principia, Newton gave a simple model for calculating the drag on an object in a moving fluid. He demonstrated the method with some simple shapes, and later attempts were made to predict the drag on real world objects such as boats. However Newton's model proved incorrect and was eventually abandoned. Hundreds of years later, with the advent of hypersonic flows, Newton's method has been resurrected. This will be a brief overview of how an incorrect 17th century theory of boat drag can be successfully applied to atmospheric entry problems, such as the recent landing of the Curiosity rover on Mars.