A mathematical model of the multiphase flow in the antroduodenum: consideration of the digestive enzymes and regulation processes

N. Zaitseva, M. Kamaltdinov, P. Trusov

Abstract: This work is aims to a problem of enhancement of a multiphase flow model in the antroduodenum, which was developed previously. New elements of the model were introduced: bile acids, pancreatic (trypsin, amylase, lipase) and intestinal (glycosidases, peptidases) enzymes, products of enzymatic reactions. Mass sources due to enzymatic reactions were described by Michaelis-Menten equation modified by the dependency on the acidity. To describe the mass sources due to secretion of the hydrochloric acid and pepsin regulatory nervous elements were added. It was assumed that receptors determine acidity in the duodenum and send signals to change the strength of the acid and enzymes sources in the stomach. The peristaltic parameters were modified by the dependency on the concentration of the dissolved food components. Using computational simulation we can predict flow characteristics at any point of the antroduodenum (medium pH, velocities and mass fractions of the phases and components). In some scenarios we analysed the influence of secretory and regulatory disorders on the acidity in distinct tract areas. The quality of food decomposition was also investigated.

Keywords: Multiphase flow, stomach, duodenum, acidity, enzymes, neuroendocrine regulation, computational simulation

Series on Biomechanics, Vol.32, No.3 (2018), 36-42

Keywords: acidity; computational simulation; duodenum; enzymes; Multiphase flow; neuroendocrine regulation; stomach

Date published: 2018-12-16