Investigating crime scenes with a physics-based blood droplet analysis

Image: Brandon Anderson - A fabric's physical properties, such as its wettability and porosity, affect the dynamics of an impacting droplet. Understanding these effects can help forensic scientists draw a better picture of a crime scene. In a paper that appeared in Physics of Fluids, UvA-physicist Thijs de Goede and collaborators from UvA, ETH Zürich, Empa (Switzerland) and the University of Sherbrooke (Canada) develop a physics-based approach to blood droplet analysis. Picture a crime scene: Different types of fabrics, all stained with drops of blood. Some of the stains are little, splattered threads; some have soaked through the cloth. How can forensic scientists decipher meaning from the shapes of these stains? To help solve this problem, de Goede et al. experimentally and computationally observed droplets impacting onto fabrics.