Modelling of cracking in evaporating, particle-laden sessile drops

Biological fluids can exhibit a variety of complex phenomenon. For example, during evaporation complex particle-laden droplets exhibit a gel transition at the contact line. This gel subsequently invades into the fluid phase and cracks. The resultant crack pattern can give an insight into the initial composition of the fluid. The cracking process itself is not well understood, with experimental observations giving multiple potential reasons. To further understand why and how these gels crack, we study the fracture of solid annuli within the framework of the Griffith theory. Under a quasi-static assumption, we consider hypotheses presented within the literature for two-dimensional annuli.