Longitudinal wall motion during peristalsis and its effect on reflux

In this study, for the first time, we consider longitudinal motion of walls during peristalsis in a distensible tube and how affects backward (or retrograde) flow, i.e. peristaltic reflux. Building on analytical model developed by Shapiro et al. ( J. Fluid Mech. , vol. 37, no. 4, 1969, pp. 799–825) based lubrication theory, as two-dimensional infinite sinusoidal wavetrain. We develop an objective function with high mechanical pumping efficiency low reflux to find optimal conditions. show that wall contributes substantially limiting peristalsis. The results suggest form velocity is linear transverse coordinate, moving forward wave when distended retracting contracted. Our are general agreement clinical observations ureteral