Performance of liquid jet generated by electromagnetic actuator and its applications

This research aims to study the performance of and applications of high speed liquid jet, which was generated by electromagnetic actuator and using electric power storage for jet generation. The jet generation device was designed and manufactured based on an impact driven method. The device can produce both impulsive jet and semi-continuous jet. From the study on the performance of impulsive jet and semi-continuous jet generation, it was found that the jet velocity and impact pressure increased and decreased when the orifice diameter of nozzle and the frequency of signal supplied to power amplifiers increased. Moveover, the jet velocity and impact pressure increased when the capacitor voltage and traveling distance increased, whereas they decreased as increasing of the liquid volume. From the study on the influence of Non-Newtonian fluid jet on jet velocity and impact pressure, it was found that types of Non-Newtonian fluid had not significant effect on jet velocity and impact pressure in the air. While types of Non-Newtonian fluid jet has significant effect on jet velocity and impact pressure in water. From the study of the jet applications, it was found that the jet generator device can be applied for drug delivery. The distance of penetration of the jet in Polyacrylamide gel depended on the jet velocity and impact pressure, whereas the dispersion distance depended on liquid volume of the jet. From the jet application for the bone drilling, it was found that the hole depth in the bone increased as the liquid volume of the jet and the number of jet pulses increased. The maximum depth was 4.52 mm at 80 jet pulses, which has the depth per liquid volume ratio of 0.113 mm/mL. For the study of the stone drilling, it was found that the hole depth in the sandstone increased when the number of jet pulses increased. The shear failure mechanisms and tensile failure mechanisms were generated on the surface of sandstone. From the effect of the inside diameter of pipe on jet velocity and impact pressure, it was found that the inside diameter of pipes had an insignificant effect on jet velocity and impact pressure. Finally, the study of a semi-continuous jet generated by an electromagnetic actuator was conducted. The maximum jet velocity and maximum impact pressure of the semi-continuous jet was 54.58 m/s and 9.89 MPa, respectively, at the 50 Hz of frequency signal supplied to the power amplifier. For the medical application of semi-continuous jet, it was found that the device can be applied for needle free jet injection as same as the commercial needle free jet injection devices. Therefore, the jet generation device created by electromagnetic actuators and using electric power storage can be applied for engineering works and medical work in the future.