PSI - Issue 65

Galina Eremina et al. / Procedia Structural Integrity 65 (2024) 92–96 Galina Eremina, Alexey Smolin / Structural Integrity Procedia 00 (2024) 000–000

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2.2. Validation of model tumor tissue

Most often, a cancer tumor is modeled as a spherical object. To validate the poroelastic model of cancer tissue, a geometric model was constructed consisting of a sphere of large (5 mm) radius and a sphere of small radius (2 mm) placed inside it. The spheres were assigned poroelastic characteristics of cancer tissue similar as in the article Hu et al. (2022). The loading was specified through the inner sphere by applied speed, the inside was used as a piston (Fig. 1a). The fluid pressure parameter (Fig. 1b) in the pores was estimated when the solid matrix pressure reached 9.5 Pa along the perimeter of the inner core (tensile stress was estimated). The cancer tumor model was validated by comparison with the computer simulation data (Fig. 1c) presented in the work Jin (2021). The obtained results showed that the used cancer cell tissue model effectively allows describing the processes of deformation, nutrient transfer, etc. in tumor tissues. The description of the validation of the bone tissue model is given in the articles Eremina et al. (2021); Smolin et al., (2021).

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Fig. 1. Validation of a cancer tissue model: (a) loading conditions; (b) fluid pressure distribution in the sample; (c) fluid pressure as a function of distance from the center of the model sample.

2.3. Model description of shock wave treatment on the mesovolume of bone with tumor

To study the therapeutic effect of shock wave on the neoplastic process in the bone matrix, mechanical loading was simulated on a model sample consisting of healthy bone and tumour tissues. The spherical cancerous tumour area was placed in a cubic bone matrix with dimensions of 5×5×5 mm (Fig. 2a). The poroelastic properties of the cancellous bone tissue of the spine and the cancerous tumour are given in Table 1. The copper applicator was located in close proximity to the affected area on top of the model sample. Loading was carried out by setting the vertical velocity of the copper plate automata (Fig. 2b).

Fig. 2. Shock wave loading of a bone matrix section with a cancerous tumor: (a) mesomodel of a cancerous tumor in a matrix with loading