Continuous fracture of soft tissue under high-speed waterjet impact and its quantification method

• Published in: Mechanics of materials 2020-12, Vol.151, p.103631, Article 103631
• Main Authors: Cao, Chao, Li, Guilin, Jin, Xin, Ding, Haigang, Zhao, Jiyun
• Format: Article
• Language: English
• Subjects: Continuous fracture; Elastic energy; High frequency deformation; Medical waterjet; RBF neural Network
• ISSN: 0167-6636; 1872-7743
• DOI: 10.1016/j.mechmat.2020.103631

The separation behavior of soft tissue under the impact of a high-speed waterjet is actually the effect of continuous fracture, which is accompanied by elastic deformation of the soft tissue. The dynamic monitoring and quantification of deformation behavior is of great significance to understand the mechanisms of fracture and separation of soft tissues. As a common soft tissue substitute, the dynamic separation process of gelatin samples under high-speed waterjet impact was quantified by optical methods. This study found that the deformation of soft tissue under high-speed waterjet impact has a large frequency, indicating that the elastic energy of soft tissue is alternately released and stored under waterjet impact. Based on the Radial Basis Function (RBF) neural network and adjacent average method, the elastic energy storage and release frequency and amplitude during the separation process were reduced and extracted through the reduction model, which provided a reliable method for the numerical quantification research of the fracture mechanics of the soft tissue separation process. The reduction model has stronger reducibility in the impact depth range of approximately 3 mm. The results show that the greater the frequency of dynamic deformation, the greater the average amplitude. Under the same impact conditions, the elastic energy storage and release of the tissue with a smaller elastic modulus during impact separation is more intense, and its utilization of the waterjet kinetic energy is lower, that is, the energy conversion efficiency of the waterjet kinetic energy into the tissue fracture energy is lower. •The continuous fracture of soft tissue is accompanied by dynamic deformation.•It was found that deformation of soft tissue under high-speed waterjet impact has large frequency.•A reduction model of deformation was established based on RBF neural network.•The deformation frequency and amplitude were extracted through the reduction model.•The elastic deformation in the process of separation determine the fracture energy utilization.