New design of the magnetic fluid linear pump to reduce the discontinuities of the pumping forces

In this research, a new design to reduce the discontinuities of the pumping forces of the magnetic fluid linear pump (MFLP) is studied. Continuous pumping of the newly designed MFLP by using ac current with a phase shift increases pumping efficiency and reduces the pumping shock. Forming shapes of the magnetic fluid at the intermediate state are computed and compared to measurement. Because the back flow of the fluid is reduced remarkably, 4-yoke ac driving is more efficient than 7-yoke dc driving. The size, weight, and pumping discontinuity is also reduced.