Fenômenos de transferência e de superfície na análise de padrões de manchas de sangue em substrato têxtil

Abstract

Bloodstain Pattern Analysis (BPA) is a well-established forensic technique in several countries, though still underutilized and insufficiently systematized in Brazil. This study aims to systematically analyze scientific publications on BPA emphasizing Transport Phenomena (momentum, mass, and heat) and Surface Phenomena, especially when applied to textile substrates—common pieces of physical evidence at crime scenes. The relevance of this research lies in the strategic role BPA plays in solving homicides and the current knowledge gap regarding how textile surfaces influence the morphology of bloodstains. A Systematic Literature Review was conducted using the ProKnow-C method, involving the construction, filtering, and bibliometric and theoretical analysis of a portfolio comprising 107 articles. The bibliometric analysis revealed a growing academic interest since 2005, highlighting key authors and journals such as Attinger, Taylor, Brutin, and Forensic Science International. The theoretical review indicated that the studies—although to varying degrees recognize the influence of physical phenomena in bloodstain formation and interpretation, using concepts such as Reynolds number, surface tension, capillary diffusion, and impact velocity. The study also presented a set of physical and mathematical expressions applicable to BPA, structured into tables by type of phenomenon. One of the main findings is that the final appearance of a bloodstain on fabric is strongly affected by the fluid’s properties and the structure, porosity, composition, and history of the substrate. Hydrophilic and porous fabrics like cotton create diffuse stains with irregular borders, whereas synthetic materials like polyester form more concentrated and well-defined stains. Recent studies have also highlighted the impact of humidity and surface treatments on blood absorption and spread. The data emphasize unresolved methodological issues, such as the challenge of differentiating transfer stains from projected patterns and the lack of quantitative models specifically designed for textile substrates. This study concludes that applying concepts from fluid dynamics and transport phenomena and deeper experimental validation can contribute to developing more robust and replicable forensic protocols. Ultimately, the research seeks to support the advancement of BPA in Brazil, reinforce its interdisciplinary theoretical foundations, and encourage further studies focused on textiles and physical modeling.