Evolution of gas bubbles in the circulation with application to the bends

Deep sea divers suffer from decompression sickness (DCS) when their rate of ascent to the surface is too quick. When the ambient pressure drops, inert gas bubbles are usually formed in blood vessels and tissues of divers. The evolution of a gas bubble in a straight tube filled with slowly moving fluid is studied by solving a coupled system of fluid-flow and gas transport equations.
 
Halpern, D., Jiang, Y. and Himm, J.F. Mathematical modeling of gas bubble evolution in a straight tube. J. Biomech. Eng. 121(5): 505, 1999.