Dynamics of Waves in Hydrogels

Valentina Kosmerl; Alexander L Yarin

Dynamics of Waves in Hydrogels

ORAL

Abstract

Dynamics of compression/rarefaction in hydrogels is an emerging new field of fluid mechanics. In the present work it is treated in the framework of forensic research. Formation of the blood and brain tissue backspatter after penetrating gunshots to the head is preceded and driven by formation and evolution of the bullet channel and filling it with muzzle gases and/or the surrounding air. This process is accompanied by formation and propagation of compression/rarefaction waves in such a hydrogel as brain tissue is. In the present work the dynamics of waves is explored using novel rheological constitutive equation of brain tissue. The equations of motion supplemented by this constitutive equation reveal the dynamics of the compression and rarefaction waves propagating through brain tissue following the formation of bullet channel filled with muzzle gases resulting from a short-range shooting. The predicted wave propagation and reflection from a skull and the bullet channel surface proceeds in concert with gas inflow and outflow from the bullet channel, as well as by fragmentation of brain tissue, with the debris issued into the channel, entrained by the outflowing gas, and formation of backspatter toward a gun bore.

Nov. 20, 2023, 5:30 PM – Nov. 20, 2023, 5:43 PM

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Presenters

Valentina Kosmerl

University of Illinois at Chicago

Authors

Valentina Kosmerl

University of Illinois at Chicago
Alexander L Yarin

University of Illinois Chicago, University of Illinois at Chicago