Finite element (FE) modeling the motion of deformable bodies within a fluid, as well as the interaction between the bodies, has been a continuous challenge over the years. There are in principle two approaches – loose and strong coupling between the FE models of the two domains, with their advantages and drawbacks. We here present our concept...

By Velibor Isailović, Miljan Milošević, Nikola Kojić, Miloš Kojić

Mass transport is a fundamental process in living organisms, responsible for the delivery of oxygen, nutrients, and drugs from blood vessels to tissues, as well as the removal of waste products back to the vascular and lymphatic systems. This exchange occurs across various biological barriers, including blood vessel walls and cellular membranes, an...

By Vladimir Simić, Miljan Milošević, Bodan Milićević, E.J. Koay, Xuewu Liu, Antonio Martino, Rossana Terracciano, Carly Filgueira, Miloš Kojić

The extremely complex biological and biochemical processes are mainly treated by laboratory and clinical investigations. In recent decades, the application of computational modeling has become more important in research and applications in the medical sciences. Despite enormous efforts and achievements in this modeling, there is still a need for ne...

By Miloš Kojić, Miljan Milošević, Vladimir Simić, Bogdan Milićević

This paper presents the integration of muscle fatigue modeling into the finite element solver PAK, based on an extended version of Hill’s phenomenological model. While traditional muscle models focus primarily on force generation, this study incorporates fatigue dynamics to provide a more realistic representation of muscle performance over ti...

By Boban Stojanović, Miloš Kojić, Srboljub Mijailovich

This paper describes software developed based on numerical implementation of algorithms for coupled acoustic – structure interaction. This class of problems implies coupling of the fluid domain, with sound wave propagation, and the domain of solid, which vibrates under the pressure caused by sound waves from the fluid domain. The physical beh...

By Velibor Isailović, Nenad Filipović, Milica Nikolić, Miloš Kojić

Cardiovascular diseases are among the leading causes of mortality worldwide, necessitating advanced computational modeling to study their underlying mechanisms and explore potential treatments. In this paper, we present a multiphysics computational model that integrates cardiac mechanics, electrophysiology, and mass transport, implemented within th...

By Miljan Milošević, Bogdan Milićević, Vladimir Simić, Nenad Filipović, Miloš Kojić

The previously formulated finite element for lung mechanics (MSCL) by the author is extended to include airflow and molecular transport by diffusion. The lung mechanics is analyzed in detail providing an insight into the deformation of the microstructural elements. Also, some refinements are introduced with respect to the previous model. Here, the ...

By Miloš Kojić

Heart wall tissue plays a crucial role in living organisms by generating the mechanical force for blood flow. This tissue has a complex internal structure comprised mostly of muscle cells, in which biochemical energy is transformed into mechanical active stress under rhythmical electrical excitation. The overall heart functioning depends, among oth...

By Miloš Kojić, Miljan Milošević, Bogdan Milićević, Vlada Geroski, Vlada Simić, D. Trifunović, G. Stanković, Nenad Filipović

The lungs are the pair of organs where very complex internal microstructure provides gas exchange as the vital process of living organisms. This exchange in humans occurs within only 300g of tissue but on the surface of millions of alveoli with the total surface area of around 130m2. The extremely complex microstructure consists of micron-size inte...

By Milos Kojic

A generalization of the smeared concept for field problems, published in recent papers of the author and his collaborators, is presented in the paper. A composite smeared finite element CSFE is formulated. This generalization can serve as a theoretical background for further applications. A selected numerical example, related to convective-diffusiv...

By Milos Kojic