Electrohydrodynamic peristaltic flow of a viscoelastic Oldroyd fluid with a mild stenosis: application of an endoscope

The effect of a vertical alternating current, electric field, and heat transfer on a peristaltic flow of a dielectric viscoelastic Oldroyd fluid is studied. This analysis involves uniform and non-uniform annuli having a mild stenosis. The analytical solutions of equations of motion are based on the perturbation technique. This technique depends on two parameters: amplitude ratio and small wave number. Numerical calculations are performed to obtain the effects of several parameters, such as the electrical Rayleigh number, temperature gradient, Reynolds number, wave number, maximum height of stenosis, and Weissenberg numbers, on the distributions of velocity, temperature, electric potential, and wall shear stress. It is found that the above-mentioned distributions in the case of a convergent tapered tube are larger than those in the case of a non-tapered one as well as a diverging tapered tube.