Flow pattern characteristics depending on angle of inclination of bloodstained surface

The aim of this study is to determine the flow pattern characteristics depending on the angle of inclination of the surface on which bloodstains are formed. A large drip of donor human blood 80 µL was used. Experimental rectilinear strip-shaped flow patterns on the glass were obtained. The surface had a inclination of 30°, 45°, 60°, 75°. With increasing inclination angle, the length of the flow patterns increases from 24.5±0.07 to 48.3±0.02 cm, while the width decreases from 0.8±0.04 to 0.5±0.03 cm. The elements of the flow pattern structure are designated «head», «body» and end part. It is proposed to distinguish two types of flow pattern: the first one is formed when blood flows out of wound, the second one is formed when a drip or a limited blood mass falls on vertical or inclined surface.