A NOVEL HYDRO MAGNETIC MICRO-PUMP AND FLOW CONTROLLER

In order to deal with the limitations of micro-pumps and micro-valves and meet the advantages of magnetic systems a novel plan is described here, The idea behind the plan is that magnetic particles, mixed and dispersed in a carrier liquid, can be accumulated and retained at specific sites to form pistons in a micro-tube using some external magnetic field sources along the tube. In other words, using some solenoids and switching them on and off in a specific order and period, causes the desired external magnetic field variation through the tube. Changing the period and the mode of activation and deactivation of the solenoids, which are called switching time and switching mode, respectively, flow can either be pumped or controlled. It is to note that, if it is required, ferro-magnetic particles can be extracted and recharged to the flow. In this research a pressure driven setup has been fabricated to make the above idea feasible to execute. The effect of the working fluid, switching time, and different concentrations on the flow rate were investigated. The experimental results corresponded to an optimum switching mode for nickel particle of diameter less than 10 microns for a constant pressure head. In order to obtain both pumping and valving characteristics of the setup, switching time was varied from 0.01 s to 5.0 s. The graphs obtained from the experiments show that best pumping performance of the setup occurred at an optimum switching time and switching mode. In addition, concentration was an important factor that affected both pumping and valving characteristics of the setup. Also, due to the differences that exist between properties of water and ethanol, changing the working fluid to ethanol resulted in a different characteristic curve.