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This paper deals with a theoretical investigation of the peristaltic transport of a physiological fluid in a porous asymmetric channel under the action of a magnetic field. The stream function, pressure gradient, and axial velocity are studied by using appropriate analytical and numerical techniques. Effects of different physical parameters such as permeability, phase difference, wave amplitude and magnetic parameter on the velocity, pumping characteristics, streamline pattern, and trapping are investigated with particular emphasis. The computational results are presented in graphical form. The results are found to be in perfect agreement with those of a previous study carried out for a nonporous channel in the absence of a magnetic field.

Polyol Ester oil–air two-phase counter current flow experiments were performed with small diameter tubes to measure gas velocities for the counter current flow limitation point and the flow reversal point. The test section was made of a Pyrex glass tube to allow visual observation. The geometry of the test section was designed to simulate various shapes of suction lines of refrigerators. The inner diameter of the test tube was 7 mm and the height was 1 m. The inclination of the test tubes varied from vertical to crank type with various horizontal lengths. An empirical oil return criterion was suggested based on the flow reversal points. This criterion was also verified using a refrigerator test apparatus and refrigerant.