| A sphere falling through a newtonian fluid is a classic hydrodynamics problem. In this talk I will discuss the variety of interesting phenomenon observed when a sphere falls through a non-newtonian fluid. A sphere falling through a shear-thinning polymer solutions, displays "negative wake" even at small reynolds numbers. A sphere falling through micellar fluid displays an unusual behaviour, in that it does not reach a terminal velocity ; instead it oscillates as it falls. Although much experimental work has been done to study the falling sphere problem in various non-newtonian solutions, progress on the computational front has been fairly slow. At the end of the talk, I will discuss some of the computational problems encountered in simulating this problem. |