Finite element simulation of food transport through the esophageal body

Table 1 Parameters of the tissue, fluid bolus and peristaltic wave used in the model

Tissue	Muscle					Mucosa-submucosa
Geo.	Bonded no-load state		True zero-stress state			Bonded no-load state		True zero-stress state
	ri (mm)	r0 (mm)	Ri (mm)	R0 (mm)	θ (o)	ri (mm)	r0 (mm)	Ri (mm)	R0 (mm)	θ (o)
	6.49	8.28	6.49	8.49	79.4	4.12	6.49	15.7	17.7	33.9
Mat.	μel (Pa)	κ1 (Pa)	κ2	α (o)	λ0	μel (Pa)	κ1 (Pa)	κ2	α (o)	λ0
	3752	23997	17.9	45	1.11	1010	9012	50.7	50.7	1.33
Fluid	μ = 0.2 Pa.s; ρ = 0.7 kg/m3; Cν = 7.2E5 Pa.s/kg
Wave	νr = 0.5 mm/s; νι = 0.9 cm/s

Table 2 Effects of bolus viscosity, tissue properties and contraction wave on the maximal bolus radius, maximal pressure, stretch of muscle, peak pressure and transport efficiency

Parameter	rmax(mm)	Pmax(kPa)	λθ(muscle)	Ppeak(kPa)	Eff. (%)
Control (V = 7.5 mL)	5.30	4.39	1.18	9.71	31.8
μ = 0.02 Pa.s	4.48	0.75	1.10	1.24	48.7
κ1 = 2399.7 Pa	6.32	2.37	1.30	6.65	19.0
λ0 = 1	4.27	12.0	1.08	14.1	73.6
νr = 0.25 mm/s	5.30	4.39	1.18	6.25	33.9
νl = 0.38 cm/s	5.30	4.39	1.18	9.71	38.0
Control (V = 10 mL)	5.91	9.58	1.25	14.4	43.9
μ = 0.02 Pa.s	4.62	1.17	1.11	1.32	61.5
κ1 = 2399.7 Pa	7.12	7.28	1.39	9.73	22.4
λ0 = 1	4.41	14.8	1.09	15.0	80.0
νr = 0.25 mm/s	5.91	9.58	1.25	8.94	46.7
νl = 0.38 cm/s	5.91	9.58	1.25	14.4	51.2