Human digestion is a complex process wherein ingested food is broken into nutrients that can be used by the body for growth, cell maintenance, and fuel. The stomach plays a pivotal role in digestion since it receives and stores ingested food, mixes, softens and breaks it down via mechanical and chemical processing, and then undergoes digestion in a regulated manner for absorption. The goal of the current project is to develop a suite of advanced computational tools to model the digestion process in the stomach and to employ these tools to conduct a comprehensive investigation of the coupled chemo-fluid dynamic mechanisms that underlie gastric digestion. Gastric digestion is implicated in some of the most important health issues of our time: nutrition, food borne illnesses, obesity and diabetes mellitus. Together, these illnesses affect hundreds of millions of people around the world and the research conducted here will have direct application to these health conditions. The computational tools developed here will also find use in other arenas of mechanical, chemical and biomedical engineering. Student training will contribute to a cadre of scientists and engineers who are well-equipped to tackle the increasingly cross-disciplinary nature of research and engineering. Outreach to the K-12 community will leverage local connections with the Baltimore high schools, including women and minority serving institutions.
The project will develop computational tools that couple multifluid flows with biochemical reactions in dynamically deforming domains as well as first-of-their-kind models for dissolution of solid food particles via chemo-fluid mechanisms. Using these tools, new and important insights into the flow physics that drives gastric digestion in health and disease, will be generated. The physics of gastric digestion is driven by three equally important factors ? stomach motility, multifluid/multiphase fluid dynamics, and gastric chemistry and the research project tackles all three of these factors. In particular, the research will answer the following key questions: how does stomach motility determine the mixing, transport, chemical processing and emptying of multi-fluid food mixtures in the stomach? How does the pH-sensitivity of enzymatic activity combine with mixing-induced pH ``microclimates`` to modulate the chemical breakdown of carbohydrate, lipid and protein rich foods in the stomach? How are solid foods processed in the complex chemo-fluid dynamic environment of the stomach and what role do particle-fluid and particle-wall interactions play in this process?
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
